SourceBrowser

1if
 not
 modules
 then
 modules
 =
 {
 }
 end
 modules
 [
'
font-dsp
'
]
 =
 {
2    version
   =
 1
.
001
,
3    comment
   =
 "
companion to font-ini.mkiv
"
,
4    author
    =
 "
Hans Hagen, PRAGMA-ADE, Hasselt NL
"
,
5    copyright
 =
 "
PRAGMA ADE / ConTeXt Development Team
"
,
6    license
   =
 "
see context related readme files
"
7}
8
9-- many 0,0 entry/exit
10
11-- This loader went through a few iterations. First I made a ff compatible one so
12-- that we could do some basic checking. Also some verbosity was added (named
13-- glyphs). Eventually all that was dropped for a context friendly format, simply
14-- because keeping the different table models in sync too to much time. I have the
15-- old file somewhere. A positive side effect is that we get an (upto) much smaller
16-- smaller tma/tmc file. In the end the loader will be not much slower than the
17-- c based ff one.
18
19-- Being binary encoded, an opentype is rather compact. When expanded into a Lua table
20-- quite some memory can be used. This is very noticeable in the ff loader, which for
21-- a good reason uses a verbose format. However, when we use that data we create a couple
22-- of hashes. In the Lua loader we create these hashes directly, which save quite some
23-- memory.
24--
25-- We convert a font file only once and then cache it. Before creating the cached instance
26-- packing takes place: common tables get shared. After (re)loading and unpacking we then
27-- get a rather efficient internal representation of the font. In the new loader there is a
28-- pitfall. Because we use some common coverage magic we put a bit more information in
29-- the mark and cursive coverage tables than strickly needed: a reference to the coverage
30-- itself. This permits a fast lookup of the second glyph involved. In the marks we
31-- expand the class indicator to a class hash, in the cursive we use a placeholder that gets
32-- a self reference. This means that we cannot pack these subtables unless we add a unique
33-- id per entry (the same one per coverage) and that makes the tables larger. Because only a
34-- few fonts benefit from this, I decided to not do this. Experiments demonstrated that it
35-- only gives a few percent gain (on for instance husayni we can go from 845K to 828K
36-- bytecode). Better stay conceptually clean than messy compact.
37
38-- When we can reduce all basic lookups to one step we might safe a bit in the processing
39-- so then only chains are multiple.
40
41-- I used to flatten kerns here but that has been moved elsewhere because it polutes the code
42-- here and can be done fast afterwards. One can even wonder if it makes sense to do it as we
43-- pack anyway. In a similar fashion the unique placeholders in anchors in marks have been
44-- removed because packing doesn't save much there anyway.
45
46-- Although we have a bit more efficient tables in the cached files, the internals are still
47-- pretty similar. And although we have a slightly more direct coverage access the processing
48-- of node lists is not noticeable faster for latin texts, but for arabic we gain some 10%
49-- (and could probably gain a bit more).
50
51-- All this packing in the otf format is somewhat obsessive as nowadays 4K resolution
52-- multi-gig videos pass through our networks and storage and memory is abundant.
53
54-- Although we use a few table readers there i sno real gain in there (apart from having
55-- less code. After all there are often not that many demanding features.
56
57local
 next
,
 type
,
 tonumber
 =
 next
,
 type
,
 tonumber
58local
 band
 =
 bit32
.
band
59local
 extract
 =
 bit32
.
extract
60local
 bor
 =
 bit32
.
bor
61local
 lshift
 =
 bit32
.
lshift
62local
 rshift
 =
 bit32
.
rshift
63local
 gsub
 =
 string
.
gsub
64local
 lower
 =
 string
.
lower
65local
 sub
 =
 string
.
sub
66local
 strip
 =
 string
.
strip
67local
 tohash
 =
 table
.
tohash
68local
 concat
 =
 table
.
concat
69local
 copy
 =
 table
.
copy
70local
 reversed
 =
 table
.
reversed
71local
 sort
 =
 table
.
sort
72local
 insert
 =
 table
.
insert
73local
 round
 =
 math
.
round
74
75local
 settings_to_hash
  =
 utilities
.
parsers
.
settings_to_hash_colon_too
76local
 setmetatableindex
 =
 table
.
setmetatableindex
77local
 formatters
        =
 string
.
formatters
78local
 sortedkeys
        =
 table
.
sortedkeys
79local
 sortedhash
        =
 table
.
sortedhash
80local
 sequenced
         =
 table
.
sequenced
81
82local
 report
            =
 logs
.
reporter
(
"
otf reader
"
)
83
84local
 readers
           =
 fonts
.
handlers
.
otf
.
readers
85local
 streamreader
      =
 readers
.
streamreader
86
87local
 setposition
       =
 streamreader
.
setposition
88local
 getposition
       =
 streamreader
.
getposition
89local
 readuinteger
      =
 streamreader
.
readcardinal1
90local
 readushort
        =
 streamreader
.
readcardinal2
91local
 readulong
         =
 streamreader
.
readcardinal4
92local
 readinteger
       =
 streamreader
.
readinteger1
93local
 readshort
         =
 streamreader
.
readinteger2
94local
 readstring
        =
 streamreader
.
readstring
95local
 readtag
           =
 streamreader
.
readtag
96local
 readbytes
         =
 streamreader
.
readbytes
97local
 readfixed
         =
 streamreader
.
readfixed4
98local
 read2dot14
        =
 streamreader
.
read2dot14
99local
 skipshort
         =
 streamreader
.
skipshort
100local
 skipbytes
         =
 streamreader
.
skip
101local
 readbytetable
     =
 streamreader
.
readbytetable
102local
 readbyte
          =
 streamreader
.
readbyte
103local
 readcardinaltable
 =
 streamreader
.
readcardinaltable
104local
 readintegertable
  =
 streamreader
.
readintegertable
105local
 readfword
         =
 readshort
106
107local
 short
  =
 2
108local
 ushort
 =
 2
109local
 ulong
  =
 4
110
111directives
.
register
(
"
fonts.streamreader
"
,
function
(
)
112
113    streamreader
      =
 utilities
.
streams
114
115    setposition
       =
 streamreader
.
setposition
116    getposition
       =
 streamreader
.
getposition
117    readuinteger
      =
 streamreader
.
readcardinal1
118    readushort
        =
 streamreader
.
readcardinal2
119    readulong
         =
 streamreader
.
readcardinal4
120    readinteger
       =
 streamreader
.
readinteger1
121    readshort
         =
 streamreader
.
readinteger2
122    readstring
        =
 streamreader
.
readstring
123    readtag
           =
 streamreader
.
readtag
124    readbytes
         =
 streamreader
.
readbytes
125    readfixed
         =
 streamreader
.
readfixed4
126    read2dot14
        =
 streamreader
.
read2dot14
127    skipshort
         =
 streamreader
.
skipshort
128    skipbytes
         =
 streamreader
.
skip
129    readbytetable
     =
 streamreader
.
readbytetable
130    readbyte
          =
 streamreader
.
readbyte
131    readcardinaltable
 =
 streamreader
.
readcardinaltable
132    readintegertable
  =
 streamreader
.
readintegertable
133    readfword
         =
 readshort
134
135end
)
136
137local
 gsubhandlers
      =
 {
 }
138local
 gposhandlers
      =
 {
 }
139
140readers
.
gsubhandlers
    =
 gsubhandlers
141readers
.
gposhandlers
    =
 gposhandlers
142
143local
 helpers
           =
 readers
.
helpers
144local
 gotodatatable
     =
 helpers
.
gotodatatable
145local
 setvariabledata
   =
 helpers
.
setvariabledata
146
147local
 lookupidoffset
    =
 -1
    -- will become 1 when we migrate (only -1 for comparign with old)
148
149local
 classes
 =
 {
150    "
base
"
,
151    "
ligature
"
,
152    "
mark
"
,
153    "
component
"
,
154}
155
156local
 gsubtypes
 =
 {
157    "
single
"
,
158    "
multiple
"
,
159    "
alternate
"
,
160    "
ligature
"
,
161    "
context
"
,
162    "
chainedcontext
"
,
163    "
extension
"
,
164    "
reversechainedcontextsingle
"
,
165}
166
167local
 gpostypes
 =
 {
168    "
single
"
,
169    "
pair
"
,
170    "
cursive
"
,
171    "
marktobase
"
,
172    "
marktoligature
"
,
173    "
marktomark
"
,
174    "
context
"
,
175    "
chainedcontext
"
,
176    "
extension
"
,
177}
178
179local
 chaindirections
 =
 {
180    context
                     =
  0
,
181    chainedcontext
              =
  1
,
182    reversechainedcontextsingle
 =
 -1
,
183}
184
185local
 function
 setmetrics
(
data
,
where
,
tag
,
d
)
186    local
 w
 =
 data
[
where
]
187    if
 w
 then
188        local
 v
 =
 w
[
tag
]
189        if
 v
 then
190            -- it looks like some fonts set the value and not the delta
191         -- report("adding %s to %s.%s value %s",d,where,tag,v)
192            w
[
tag
]
 =
 v
 +
 d
193        end
194    end
195end
196
197local
 variabletags
 =
 {
198    hasc
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
typoascender
"
,
d
)
 end
,
199    hdsc
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
typodescender
"
,
d
)
 end
,
200    hlgp
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
typolinegap
"
,
d
)
 end
,
201    hcla
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
winascent
"
,
d
)
 end
,
202    hcld
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
windescent
"
,
d
)
 end
,
203    vasc
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
vhea not done
"
,
"
ascent
"
,
d
)
 end
,
204    vdsc
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
vhea not done
"
,
"
descent
"
,
d
)
 end
,
205    vlgp
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
vhea not done
"
,
"
linegap
"
,
d
)
 end
,
206    xhgt
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
xheight
"
,
d
)
 end
,
207    cpht
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
capheight
"
,
d
)
 end
,
208    sbxs
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
subscriptxsize
"
,
d
)
 end
,
209    sbys
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
subscriptysize
"
,
d
)
 end
,
210    sbxo
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
subscriptxoffset
"
,
d
)
 end
,
211    sbyo
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
subscriptyoffset
"
,
d
)
 end
,
212    spxs
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
superscriptxsize
"
,
d
)
 end
,
213    spys
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
superscriptysize
"
,
d
)
 end
,
214    spxo
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
superscriptxoffset
"
,
d
)
 end
,
215    spyo
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
superscriptyoffset
"
,
d
)
 end
,
216    strs
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
strikeoutsize
"
,
d
)
 end
,
217    stro
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
windowsmetrics
"
,
"
strikeoutpos
"
,
d
)
 end
,
218    unds
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
postscript
"
,
"
underlineposition
"
,
d
)
 end
,
219    undo
 =
 function
(
data
,
d
)
 setmetrics
(
data
,
"
postscript
"
,
"
underlinethickness
"
,
d
)
 end
,
220}
221
222local
 read_cardinal
 =
 {
223    streamreader
.
readcardinal1
,
224    streamreader
.
readcardinal2
,
225    streamreader
.
readcardinal3
,
226    streamreader
.
readcardinal4
,
227}
228
229local
 read_integer
 =
 {
230    streamreader
.
readinteger1
,
231    streamreader
.
readinteger2
,
232    streamreader
.
readinteger3
,
233    streamreader
.
readinteger4
,
234}
235
236-- Traditionally we use these unique names (so that we can flatten the lookup list
237-- (we create subsets runtime) but I will adapt the old code to newer names.
238
239-- chainsub
240-- reversesub
241
242local
 lookupnames
 =
 {
243    gsub
 =
 {
244        single
                      =
 "
gsub_single
"
,
245        multiple
                    =
 "
gsub_multiple
"
,
246        alternate
                   =
 "
gsub_alternate
"
,
247        ligature
                    =
 "
gsub_ligature
"
,
248        context
                     =
 "
gsub_context
"
,
249        chainedcontext
              =
 "
gsub_contextchain
"
,
250        reversechainedcontextsingle
 =
 "
gsub_reversecontextchain
"
,
 -- reversesub
251    }
,
252    gpos
 =
 {
253        single
                      =
 "
gpos_single
"
,
254        pair
                        =
 "
gpos_pair
"
,
255        cursive
                     =
 "
gpos_cursive
"
,
256        marktobase
                  =
 "
gpos_mark2base
"
,
257        marktoligature
              =
 "
gpos_mark2ligature
"
,
258        marktomark
                  =
 "
gpos_mark2mark
"
,
259        context
                     =
 "
gpos_context
"
,
260        chainedcontext
              =
 "
gpos_contextchain
"
,
261    }
262}
263
264-- keep this as reference:
265--
266-- local lookupbits = {
267--     [0x0001] = "righttoleft",
268--     [0x0002] = "ignorebaseglyphs",
269--     [0x0004] = "ignoreligatures",
270--     [0x0008] = "ignoremarks",
271--     [0x0010] = "usemarkfilteringset",
272--     [0x00E0] = "reserved",
273--     [0xFF00] = "markattachmenttype",
274-- }
275--
276-- local lookupstate = setmetatableindex(function(t,k)
277--     local v = { }
278--     for kk, vv in next, lookupbits do
279--         if band(k,kk) ~= 0 then
280--             v[vv] = true
281--         end
282--     end
283--     t[k] = v
284--     return v
285-- end)
286
287local
 lookupflags
 =
 setmetatableindex
(
function
(
t
,
k
)
288    local
 v
 =
 {
289        band
(
k
,
0x0008
)
 ~
=
 0
 and
 true
 or
 false
,
 -- ignoremarks
290        band
(
k
,
0x0004
)
 ~
=
 0
 and
 true
 or
 false
,
 -- ignoreligatures
291        band
(
k
,
0x0002
)
 ~
=
 0
 and
 true
 or
 false
,
 -- ignorebaseglyphs
292        band
(
k
,
0x0001
)
 ~
=
 0
 and
 true
 or
 false
,
 -- r2l
293    }
294    t
[
k
]
 =
 v
295    return
 v
296end
)
297
298-- Variation stores: it's not entirely clear if the regions are a shared
299-- resource (it looks like they are). Anyway, we play safe and use a
300-- share.
301
302-- values can be anything the min/max permits so we can either think of
303-- real values of a fraction along the axis (probably easier)
304
305-- wght=400,wdth=100,ital=1
306
307local
 function
 axistofactors
(
str
)
308    local
 t
 =
 settings_to_hash
(
str
)
309    for
 k
,
 v
 in
 next
,
 t
 do
310        t
[
k
]
 =
 tonumber
(
v
)
 or
 v
 -- this also normalizes numbers itself
311    end
312    return
 t
313end
314
315local
 hash
 =
 table
.
setmetatableindex
(
function
(
t
,
k
)
316    local
 v
 =
 sequenced
(
axistofactors
(
k
)
,
"
,
"
)
317    t
[
k
]
 =
 v
318    return
 v
319end
)
320
321helpers
.
normalizedaxishash
 =
 hash
322
323local
 cleanname
 =
 fonts
.
names
 and
 fonts
.
names
.
cleanname
 or
 function
(
name
)
324    return
 name
 and
 (
gsub
(
lower
(
name
)
,
"
[^%a%d]
"
,
"
"
)
)
 or
 nil
325end
326
327helpers
.
cleanname
 =
 cleanname
328
329function
 helpers
.
normalizedaxis
(
str
)
330    return
 hash
[
str
]
 or
 str
331end
332
333-- contradicting spec ... (signs) so i'll check it and fix it once we have
334-- proper fonts
335
336local
 function
 getaxisscale
(
segments
,
minimum
,
default
,
maximum
,
user
)
337    --
338    -- returns the right values cf example in standard
339    --
340    if
 not
 minimum
 or
 not
 default
 or
 not
 maximum
 then
341        return
 false
342    end
343    if
 user
 <
 minimum
 then
344        user
 =
 minimum
345    elseif
 user
 >
 maximum
 then
346        user
 =
 maximum
347    end
348    if
 user
 <
 default
 then
349        default
 =
 -
 (
default
 -
 user
)
 /
 (
default
 -
 minimum
)
350    elseif
 user
 >
 default
 then
351        default
 =
 (
user
 -
 default
)
 /
 (
maximum
 -
 default
)
352    else
353        default
 =
 0
354    end
355    if
 not
 segments
 then
356        return
 default
357    end
358    local
 e
359    for
 i
=
1
,
#
segments
 do
360        local
 s
 =
 segments
[
i
]
361        if
 type
(
s
)
 ~
=
 "
number
"
 then
362            report
(
"
using default axis scale
"
)
363            return
 default
364        elseif
 s
[
1
]
 >
=
 default
 then
365            if
 s
[
2
]
 =
=
 default
 then
366                return
 default
367            else
368                e
 =
 i
369                break
370            end
371        end
372    end
373    if
 e
 then
374        local
 b
 =
 segments
[
e
-1
]
375        local
 e
 =
 segments
[
e
]
376        return
 b
[
2
]
 +
 (
e
[
2
]
 -
 b
[
2
]
)
 *
 (
default
 -
 b
[
1
]
)
 /
 (
e
[
1
]
 -
 b
[
1
]
)
377    else
378        return
 false
379    end
380end
381
382local
 function
 getfactors
(
data
,
instancespec
)
383    if
 instancespec
 =
=
 true
 then
384        -- take default
385    elseif
 type
(
instancespec
)
 ~
=
 "
string
"
 or
 instancespec
 =
=
 "
"
 then
386        return
387    end
388    local
 variabledata
 =
 data
.
variabledata
389    if
 not
 variabledata
 then
390        return
391    end
392    local
 instances
 =
 variabledata
.
instances
393    local
 axis
      =
 variabledata
.
axis
394    local
 segments
  =
 variabledata
.
segments
395    if
 instances
 and
 axis
 then
396        local
 values
397        if
 instancespec
 =
=
 true
 then
398            -- first instance:
399         -- values = instances[1].values
400            -- axis defaults:
401            values
 =
 {
 }
402            for
 i
=
1
,
#
axis
 do
403                values
[
i
]
 =
 {
404                 -- axis  = axis[i].tag,
405                    value
 =
 axis
[
i
]
.
default
,
406                }
407            end
408
409        else
410            for
 i
=
1
,
#
instances
 do
411                local
 instance
 =
 instances
[
i
]
412                if
 cleanname
(
instance
.
subfamily
)
 =
=
 instancespec
 then
413                    values
 =
 instance
.
values
414                    break
415                end
416            end
417        end
418        if
 values
 then
419            local
 factors
 =
 {
 }
420            for
 i
=
1
,
#
axis
 do
421                local
 a
 =
 axis
[
i
]
422                factors
[
i
]
 =
 getaxisscale
(
segments
,
a
.
minimum
,
a
.
default
,
a
.
maximum
,
values
[
i
]
.
value
)
423            end
424            return
 factors
425        end
426        local
 values
 =
 axistofactors
(
hash
[
instancespec
]
 or
 instancespec
)
427        if
 values
 then
428            local
 factors
 =
 {
 }
429            for
 i
=
1
,
#
axis
 do
430                local
 a
 =
 axis
[
i
]
431                local
 d
 =
 a
.
default
432                factors
[
i
]
 =
 getaxisscale
(
segments
,
a
.
minimum
,
d
,
a
.
maximum
,
values
[
a
.
name
 or
 a
.
tag
]
 or
 d
)
433            end
434            return
 factors
435        end
436    end
437end
438
439local
 function
 getscales
(
regions
,
factors
)
440    local
 scales
 =
 {
 }
441    for
 i
=
1
,
#
regions
 do
442        local
 region
 =
 regions
[
i
]
443        local
 s
 =
 1
444        for
 j
=
1
,
#
region
 do
445            local
 axis
  =
 region
[
j
]
446            local
 f
     =
 factors
[
j
]
447            local
 start
 =
 axis
.
start
448            local
 peak
  =
 axis
.
peak
449            local
 stop
  =
 axis
.
stop
450            -- get rid of these tests, false flag
451            if
 start
 >
 peak
 or
 peak
 >
 stop
 then
452                -- * 1
453            elseif
 start
 <
 0
 and
 stop
 >
 0
 and
 peak
 ~
=
 0
 then
454                -- * 1
455            elseif
 peak
 =
=
 0
 then
456                -- * 1
457            elseif
 f
 <
 start
 or
 f
 >
 stop
 then
458                -- * 0
459                s
 =
 0
460                break
461            elseif
 f
 <
 peak
 then
462             -- s = - s * (f - start) / (peak - start)
463                s
 =
 s
 *
 (
f
 -
 start
)
 /
 (
peak
 -
 start
)
464            elseif
 f
 >
 peak
 then
465                s
 =
 s
 *
 (
stop
 -
 f
)
 /
 (
stop
 -
 peak
)
466            else
467                -- * 1
468            end
469        end
470        scales
[
i
]
 =
 s
471    end
472    return
 scales
473end
474
475helpers
.
getaxisscale
  =
 getaxisscale
476helpers
.
getfactors
    =
 getfactors
477helpers
.
getscales
     =
 getscales
478helpers
.
axistofactors
 =
 axistofactors
479
480local
 function
 readvariationdata
(
f
,
storeoffset
,
factors
)
 -- store
481    local
 position
 =
 getposition
(
f
)
482    setposition
(
f
,
storeoffset
)
483    -- header
484    local
 format
       =
 readushort
(
f
)
485    local
 regionoffset
 =
 storeoffset
 +
 readulong
(
f
)
486    local
 nofdeltadata
 =
 readushort
(
f
)
487    local
 deltadata
    =
 readcardinaltable
(
f
,
nofdeltadata
,
ulong
)
488    -- regions
489    setposition
(
f
,
regionoffset
)
490    local
 nofaxis
    =
 readushort
(
f
)
491    local
 nofregions
 =
 readushort
(
f
)
492    local
 regions
    =
 {
 }
493    for
 i
=
1
,
nofregions
 do
 -- 0
494        local
 t
 =
 {
 }
495        for
 i
=
1
,
nofaxis
 do
496            t
[
i
]
 =
 {
 -- maybe no keys, just 1..3
497                start
 =
 read2dot14
(
f
)
,
498                peak
  =
 read2dot14
(
f
)
,
499                stop
  =
 read2dot14
(
f
)
,
500            }
501        end
502        regions
[
i
]
 =
 t
503    end
504    -- deltas
505    if
 factors
 then
506        for
 i
=
1
,
nofdeltadata
 do
507            setposition
(
f
,
storeoffset
+
deltadata
[
i
]
)
508            local
 nofdeltasets
 =
 readushort
(
f
)
509            local
 nofshorts
    =
 readushort
(
f
)
510            local
 nofregions
   =
 readushort
(
f
)
511            local
 usedregions
  =
 {
 }
512            local
 deltas
       =
 {
 }
513            for
 i
=
1
,
nofregions
 do
514                usedregions
[
i
]
 =
 regions
[
readushort
(
f
)
+
1
]
515            end
516            -- we could test before and save a for
517            for
 i
=
1
,
nofdeltasets
 do
518                local
 t
 =
 readintegertable
(
f
,
nofshorts
,
short
)
519                for
 i
=
nofshorts
+
1
,
nofregions
 do
520                    t
[
i
]
 =
 readinteger
(
f
)
521                end
522                deltas
[
i
]
 =
 t
523            end
524            deltadata
[
i
]
 =
 {
525                regions
 =
 usedregions
,
526                deltas
  =
 deltas
,
527                scales
  =
 factors
 and
 getscales
(
usedregions
,
factors
)
 or
 nil
,
528            }
529        end
530    end
531    setposition
(
f
,
position
)
532    return
 regions
,
 deltadata
533end
534
535helpers
.
readvariationdata
 =
 readvariationdata
536
537-- Beware: only use the simple variant if we don't set keys/values (otherwise too many entries). We
538-- could also have a variant that applies a function but there is no real benefit in this.
539
540local
 function
 readcoverage
(
f
,
offset
,
simple
)
541    setposition
(
f
,
offset
)
542    local
 coverageformat
 =
 readushort
(
f
)
543    if
 coverageformat
 =
=
 1
 then
544        local
 nofcoverage
 =
 readushort
(
f
)
545        if
 simple
 then
546            -- often 1 or 2
547            if
 nofcoverage
 =
=
 1
 then
548                return
 {
 readushort
(
f
)
 }
549            elseif
 nofcoverage
 =
=
 2
 then
550                return
 {
 readushort
(
f
)
,
 readushort
(
f
)
 }
551            else
552                return
 readcardinaltable
(
f
,
nofcoverage
,
ushort
)
553            end
554        elseif
 nofcoverage
 =
=
 1
 then
555            return
 {
 [
readushort
(
f
)
]
 =
 0
 }
556        elseif
 nofcoverage
 =
=
 2
 then
557            return
 {
 [
readushort
(
f
)
]
 =
 0
,
 [
readushort
(
f
)
]
 =
 1
 }
558        else
559            local
 coverage
 =
 {
 }
560            for
 i
=
0
,
nofcoverage
-1
 do
561                coverage
[
readushort
(
f
)
]
 =
 i
 -- index in record
562            end
563            return
 coverage
564        end
565    elseif
 coverageformat
 =
=
 2
 then
566        local
 nofranges
 =
 readushort
(
f
)
567        local
 coverage
  =
 {
 }
568        local
 n
         =
 simple
 and
 1
 or
 0
 -- needs checking
569        for
 i
=
1
,
nofranges
 do
570            local
 firstindex
 =
 readushort
(
f
)
571            local
 lastindex
  =
 readushort
(
f
)
572            local
 coverindex
 =
 readushort
(
f
)
573            if
 simple
 then
574                for
 i
=
firstindex
,
lastindex
 do
575                    coverage
[
n
]
 =
 i
576                    n
 =
 n
 +
 1
577                end
578            else
579                for
 i
=
firstindex
,
lastindex
 do
580                    coverage
[
i
]
 =
 n
581                    n
 =
 n
 +
 1
582                end
583            end
584        end
585        return
 coverage
586    else
587        report
(
"
unknown coverage format %a 
"
,
coverageformat
)
588        return
 {
 }
589    end
590end
591
592local
 function
 readclassdef
(
f
,
offset
,
preset
)
593    setposition
(
f
,
offset
)
594    local
 classdefformat
 =
 readushort
(
f
)
595    local
 classdef
 =
 {
 }
596    if
 type
(
preset
)
 =
=
 "
number
"
 then
597        for
 k
=
0
,
preset
-1
 do
598            classdef
[
k
]
 =
 1
599        end
600    end
601    if
 classdefformat
 =
=
 1
 then
602        local
 index
       =
 readushort
(
f
)
603        local
 nofclassdef
 =
 readushort
(
f
)
604        for
 i
=
1
,
nofclassdef
 do
605            classdef
[
index
]
 =
 readushort
(
f
)
 +
 1
606            index
 =
 index
 +
 1
607        end
608    elseif
 classdefformat
 =
=
 2
 then
609        local
 nofranges
 =
 readushort
(
f
)
610        local
 n
 =
 0
611        for
 i
=
1
,
nofranges
 do
612            local
 firstindex
 =
 readushort
(
f
)
613            local
 lastindex
  =
 readushort
(
f
)
614            local
 class
      =
 readushort
(
f
)
 +
 1
615            for
 i
=
firstindex
,
lastindex
 do
616                classdef
[
i
]
 =
 class
617            end
618        end
619    else
620        report
(
"
unknown classdef format %a 
"
,
classdefformat
)
621    end
622    if
 type
(
preset
)
 =
=
 "
table
"
 then
623        for
 k
 in
 next
,
 preset
 do
624            if
 not
 classdef
[
k
]
 then
625                classdef
[
k
]
 =
 1
626            end
627        end
628    end
629    return
 classdef
630end
631
632local
 function
 classtocoverage
(
defs
)
633    if
 defs
 then
634        local
 list
 =
 {
 }
635        for
 index
,
 class
 in
 next
,
 defs
 do
636            local
 c
 =
 list
[
class
]
637            if
 c
 then
638                c
[
#
c
+
1
]
 =
 index
639            else
640                list
[
class
]
 =
 {
 index
 }
641            end
642        end
643        return
 list
644    end
645end
646
647-- extra readers
648
649local
 skips
 =
 {
 [
0
]
 =
650    0
,
 -- ----
651    1
,
 -- ---x
652    1
,
 -- --y-
653    2
,
 -- --yx
654    1
,
 -- -h--
655    2
,
 -- -h-x
656    2
,
 -- -hy-
657    3
,
 -- -hyx
658    2
,
 -- v--x
659    2
,
 -- v-y-
660    3
,
 -- v-yx
661    2
,
 -- vh--
662    3
,
 -- vh-x
663    3
,
 -- vhy-
664    4
,
 -- vhyx
665}
666
667-- We can assume that 0 is nothing and in fact we can start at 1 as
668-- usual in Lua to make sure of that.
669
670local
 function
 readvariation
(
f
,
offset
)
671    local
 p
 =
 getposition
(
f
)
672    setposition
(
f
,
offset
)
673    local
 outer
  =
 readushort
(
f
)
674    local
 inner
  =
 readushort
(
f
)
675    local
 format
 =
 readushort
(
f
)
676    setposition
(
f
,
p
)
677    if
 format
 =
=
 0x8000
 then
678        return
 outer
,
 inner
679    end
680end
681
682local
 function
 readposition
(
f
,
format
,
mainoffset
,
getdelta
)
683    if
 format
 =
=
 0
 then
684        return
 false
685    end
686    -- a few happen often
687    if
 format
 =
=
 0x04
 then
688        local
 h
 =
 readshort
(
f
)
689        if
 h
 =
=
 0
 then
690            return
 true
 -- all zero
691        else
692            return
 {
 0
,
 0
,
 h
,
 0
 }
693        end
694    end
695    if
 format
 =
=
 0x05
 then
696        local
 x
 =
 readshort
(
f
)
697        local
 h
 =
 readshort
(
f
)
698        if
 x
 =
=
 0
 and
 h
 =
=
 0
 then
699            return
 true
 -- all zero
700        else
701            return
 {
 x
,
 0
,
 h
,
 0
 }
702        end
703    end
704    if
 format
 =
=
 0x44
 then
705        local
 h
 =
 readshort
(
f
)
706        if
 getdelta
 then
707            local
 d
 =
 readshort
(
f
)
 -- short or ushort
708            if
 d
 >
 0
 then
709                local
 outer
,
 inner
 =
 readvariation
(
f
,
mainoffset
+
d
)
710                if
 outer
 then
711                    h
 =
 h
 +
 getdelta
(
outer
,
inner
)
712                end
713            end
714        else
715            skipshort
(
f
,
1
)
716        end
717        if
 h
 =
=
 0
 then
718            return
 true
 -- all zero
719        else
720            return
 {
 0
,
 0
,
 h
,
 0
 }
721        end
722    end
723    --
724    -- todo:
725    --
726    -- if format == 0x55 then
727    --     local x = readshort(f)
728    --     local h = readshort(f)
729    --     ....
730    -- end
731    --
732    local
 x
 =
 band
(
format
,
0x1
)
 ~
=
 0
 and
 readshort
(
f
)
 or
 0
 -- x placement
733    local
 y
 =
 band
(
format
,
0x2
)
 ~
=
 0
 and
 readshort
(
f
)
 or
 0
 -- y placement
734    local
 h
 =
 band
(
format
,
0x4
)
 ~
=
 0
 and
 readshort
(
f
)
 or
 0
 -- h advance
735    local
 v
 =
 band
(
format
,
0x8
)
 ~
=
 0
 and
 readshort
(
f
)
 or
 0
 -- v advance
736    if
 format
 >
=
 0x10
 then
737        local
 X
 =
 band
(
format
,
0x10
)
 ~
=
 0
 and
 skipshort
(
f
)
 or
 0
738        local
 Y
 =
 band
(
format
,
0x20
)
 ~
=
 0
 and
 skipshort
(
f
)
 or
 0
739        local
 H
 =
 band
(
format
,
0x40
)
 ~
=
 0
 and
 skipshort
(
f
)
 or
 0
740        local
 V
 =
 band
(
format
,
0x80
)
 ~
=
 0
 and
 skipshort
(
f
)
 or
 0
741        local
 s
 =
 skips
[
extract
(
format
,
4
,
4
)
]
742        if
 s
 >
 0
 then
743            skipshort
(
f
,
s
)
744        end
745        if
 getdelta
 then
746            if
 X
 >
 0
 then
747                local
 outer
,
 inner
 =
 readvariation
(
f
,
mainoffset
+
X
)
748                if
 outer
 then
749                    x
 =
 x
 +
 getdelta
(
outer
,
inner
)
750                end
751            end
752            if
 Y
 >
 0
 then
753                local
 outer
,
 inner
 =
 readvariation
(
f
,
mainoffset
+
Y
)
754                if
 outer
 then
755                    y
 =
 y
 +
 getdelta
(
outer
,
inner
)
756                end
757            end
758            if
 H
 >
 0
 then
759                local
 outer
,
 inner
 =
 readvariation
(
f
,
mainoffset
+
H
)
760                if
 outer
 then
761                    h
 =
 h
 +
 getdelta
(
outer
,
inner
)
762                end
763            end
764            if
 V
 >
 0
 then
765                local
 outer
,
 inner
 =
 readvariation
(
f
,
mainoffset
+
V
)
766                if
 outer
 then
767                    v
 =
 v
 +
 getdelta
(
outer
,
inner
)
768                end
769            end
770        end
771        return
 {
 x
,
 y
,
 h
,
 v
 }
772    elseif
 x
 =
=
 0
 and
 y
 =
=
 0
 and
 h
 =
=
 0
 and
 v
 =
=
 0
 then
773        return
 true
 -- all zero
774    else
775        return
 {
 x
,
 y
,
 h
,
 v
 }
776    end
777end
778
779local
 function
 readanchor
(
f
,
offset
,
getdelta
)
 -- maybe also ignore 0's as in pos
780    if
 not
 offset
 or
 offset
 =
=
 0
 then
781        return
 nil
 -- false
782    end
783    setposition
(
f
,
offset
)
784    -- no need to skip as we position each
785    local
 format
 =
 readshort
(
f
)
 -- 1: x y 2: x y index 3 x y X Y
786    local
 x
 =
 readshort
(
f
)
787    local
 y
 =
 readshort
(
f
)
788    if
 format
 =
=
 3
 then
789        if
 getdelta
 then
790            local
 X
 =
 readshort
(
f
)
791            local
 Y
 =
 readshort
(
f
)
792            if
 X
 >
 0
 then
793                local
 outer
,
 inner
 =
 readvariation
(
f
,
offset
+
X
)
794                if
 outer
 then
795                    x
 =
 x
 +
 getdelta
(
outer
,
inner
)
796                end
797            end
798            if
 Y
 >
 0
 then
799                local
 outer
,
 inner
 =
 readvariation
(
f
,
offset
+
Y
)
800                if
 outer
 then
801                    y
 =
 y
 +
 getdelta
(
outer
,
inner
)
802                end
803            end
804        else
805            skipshort
(
f
,
2
)
806        end
807        return
 {
 x
,
 y
 }
 -- , { xindex, yindex }
808    else
809        return
 {
 x
,
 y
 }
810    end
811end
812
813-- common handlers: inlining can be faster but we cache anyway
814-- so we don't bother too much about speed here
815
816local
 function
 readfirst
(
f
,
offset
)
817    if
 offset
 then
818        setposition
(
f
,
offset
)
819    end
820    return
 {
 readushort
(
f
)
 }
821end
822
823-- quite often 0, 1, 2
824
825function
 readarray
(
f
,
offset
)
826    if
 offset
 then
827        setposition
(
f
,
offset
)
828    end
829    local
 n
 =
 readushort
(
f
)
830    if
 n
 =
=
 1
 then
831        return
 {
 readushort
(
f
)
 }
,
 1
832    elseif
 n
 >
 0
 then
833        return
 readcardinaltable
(
f
,
n
,
ushort
)
,
 n
834    end
835end
836
837local
 function
 readcoveragearray
(
f
,
offset
,
t
,
simple
)
838    if
 not
 t
 then
839        return
 nil
840    end
841    local
 n
 =
 #
t
842    if
 n
 =
=
 0
 then
843        return
 nil
844    end
845    for
 i
=
1
,
n
 do
846        t
[
i
]
 =
 readcoverage
(
f
,
offset
+
t
[
i
]
,
simple
)
847    end
848    return
 t
849end
850
851local
 function
 covered
(
subset
,
all
)
852    local
 used
,
 u
853    for
 i
=
1
,
#
subset
 do
854        local
 s
 =
 subset
[
i
]
855        if
 all
[
s
]
 then
856            if
 used
 then
857                u
 =
 u
 +
 1
858                used
[
u
]
 =
 s
859            else
860                u
 =
 1
861                used
 =
 {
 s
 }
862            end
863        end
864    end
865    return
 used
866end
867
868-- We generalize the chained lookups so that we can do with only one handler
869-- when processing them.
870
871-- pruned
872
873local
 function
 readlookuparray
(
f
,
noflookups
,
nofcurrent
)
874    local
 lookups
 =
 {
 }
875    if
 noflookups
 >
 0
 then
876        local
 length
 =
 0
877        for
 i
=
1
,
noflookups
 do
878            local
 index
 =
 readushort
(
f
)
 +
 1
879            if
 index
 >
 length
 then
880                length
 =
 index
881            end
882            local
 lookup
 =
 readushort
(
f
)
 +
 1
883            local
 list
   =
 lookups
[
index
]
884            if
 list
 then
885                list
[
#
list
+
1
]
 =
 lookup
886            else
887                lookups
[
index
]
 =
 {
 lookup
 }
888            end
889        end
890        for
 index
=
1
,
length
 do
891            if
 not
 lookups
[
index
]
 then
892                lookups
[
index
]
 =
 false
893            end
894        end
895     -- if length > nofcurrent then
896     --     report("more lookups than currently matched characters")
897     -- end
898    end
899    return
 lookups
900end
901
902-- not pruned
903--
904-- local function readlookuparray(f,noflookups,nofcurrent)
905--     local lookups = { }
906--     for i=1,nofcurrent do
907--         lookups[i] = false
908--     end
909--     for i=1,noflookups do
910--         local index = readushort(f) + 1
911--         if index > nofcurrent then
912--             report("more lookups than currently matched characters")
913--             for i=nofcurrent+1,index-1 do
914--                 lookups[i] = false
915--             end
916--             nofcurrent = index
917--         end
918--         lookups[index] = readushort(f) + 1
919--     end
920--     return lookups
921-- end
922
923local
 function
 unchainedcontext
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
what
)
924    local
 tableoffset
 =
 lookupoffset
 +
 offset
925    setposition
(
f
,
tableoffset
)
926    local
 subtype
 =
 readushort
(
f
)
927    if
 subtype
 =
=
 1
 then
928        local
 coverage
     =
 readushort
(
f
)
929        local
 subclasssets
 =
 readarray
(
f
)
930        local
 rules
        =
 {
 }
931        if
 subclasssets
 then
932            coverage
 =
 readcoverage
(
f
,
tableoffset
+
coverage
,
true
)
933            for
 i
=
1
,
#
subclasssets
 do
934                local
 offset
 =
 subclasssets
[
i
]
935                if
 offset
 >
 0
 then
936                    local
 firstcoverage
 =
 coverage
[
i
]
937                    local
 rulesoffset
   =
 tableoffset
 +
 offset
938                    local
 subclassrules
 =
 readarray
(
f
,
rulesoffset
)
939                    for
 rule
=
1
,
#
subclassrules
 do
940                        setposition
(
f
,
rulesoffset
 +
 subclassrules
[
rule
]
)
941                        local
 nofcurrent
 =
 readushort
(
f
)
942                        local
 noflookups
 =
 readushort
(
f
)
943                        local
 current
    =
 {
 {
 firstcoverage
 }
 }
944                        for
 i
=
2
,
nofcurrent
 do
945                            current
[
i
]
 =
 {
 readushort
(
f
)
 }
946                        end
947                        local
 lookups
 =
 readlookuparray
(
f
,
noflookups
,
nofcurrent
)
948                        rules
[
#
rules
+
1
]
 =
 {
949                            current
 =
 current
,
950                            lookups
 =
 lookups
951                        }
952                    end
953                end
954            end
955        else
956            report
(
"
empty subclassset in %a subtype %i
"
,
"
unchainedcontext
"
,
subtype
)
957        end
958        return
 {
959            format
 =
 "
glyphs
"
,
960            rules
  =
 rules
,
961        }
962    elseif
 subtype
 =
=
 2
 then
963        -- We expand the classes as later on we do a pack over the whole table so then we get
964        -- back efficiency. This way we can also apply the coverage to the first current.
965        local
 coverage
        =
 readushort
(
f
)
966        local
 currentclassdef
 =
 readushort
(
f
)
967        local
 subclasssets
    =
 readarray
(
f
)
968        local
 rules
           =
 {
 }
969        if
 subclasssets
 then
970            coverage
             =
 readcoverage
(
f
,
tableoffset
 +
 coverage
)
971            currentclassdef
      =
 readclassdef
(
f
,
tableoffset
 +
 currentclassdef
,
coverage
)
972            local
 currentclasses
 =
 classtocoverage
(
currentclassdef
,
fontdata
.
glyphs
)
973            for
 class
=
1
,
#
subclasssets
 do
974                local
 offset
 =
 subclasssets
[
class
]
975                if
 offset
 >
 0
 then
976                    local
 firstcoverage
 =
 currentclasses
[
class
]
977                    if
 firstcoverage
 then
978                        firstcoverage
 =
 covered
(
firstcoverage
,
coverage
)
 -- bonus
979                        if
 firstcoverage
 then
980                            local
 rulesoffset
   =
 tableoffset
 +
 offset
981                            local
 subclassrules
 =
 readarray
(
f
,
rulesoffset
)
982                            for
 rule
=
1
,
#
subclassrules
 do
983                                setposition
(
f
,
rulesoffset
 +
 subclassrules
[
rule
]
)
984                                local
 nofcurrent
 =
 readushort
(
f
)
985                                local
 noflookups
 =
 readushort
(
f
)
986                                local
 current
    =
 {
 firstcoverage
 }
987                                for
 i
=
2
,
nofcurrent
 do
988                                    current
[
i
]
 =
 currentclasses
[
readushort
(
f
)
 +
 1
]
989                                end
990                                local
 lookups
 =
 readlookuparray
(
f
,
noflookups
,
nofcurrent
)
991                                rules
[
#
rules
+
1
]
 =
 {
992                                    current
 =
 current
,
993                                    lookups
 =
 lookups
994                                }
995                            end
996                        else
997                            report
(
"
no coverage
"
)
998                        end
999                    else
1000                        report
(
"
no coverage class
"
)
1001                    end
1002                end
1003            end
1004        else
1005            report
(
"
empty subclassset in %a subtype %i
"
,
"
unchainedcontext
"
,
subtype
)
1006        end
1007        return
 {
1008            format
 =
 "
class
"
,
1009            rules
  =
 rules
,
1010        }
1011    elseif
 subtype
 =
=
 3
 then
1012        local
 nofglyphs
  =
 readushort
(
f
)
1013        local
 noflookups
 =
 readushort
(
f
)
1014        local
 current
    =
 readcardinaltable
(
f
,
nofglyphs
,
ushort
)
1015        local
 lookups
    =
 readlookuparray
(
f
,
noflookups
,
#
current
)
1016        current
 =
 readcoveragearray
(
f
,
tableoffset
,
current
,
true
)
1017        return
 {
1018            format
 =
 "
coverage
"
,
1019            rules
  =
 {
1020                {
1021                    current
 =
 current
,
1022                    lookups
 =
 lookups
,
1023                }
1024            }
1025        }
1026    else
1027        report
(
"
unsupported subtype %a in %a %s
"
,
subtype
,
"
unchainedcontext
"
,
what
)
1028    end
1029end
1030
1031-- todo: optimize for n=1 ?
1032
1033-- class index needs checking, probably no need for +1
1034
1035local
 function
 chainedcontext
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
what
)
1036    local
 tableoffset
 =
 lookupoffset
 +
 offset
1037    setposition
(
f
,
tableoffset
)
1038    local
 subtype
 =
 readushort
(
f
)
1039    if
 subtype
 =
=
 1
 then
1040        local
 coverage
     =
 readushort
(
f
)
1041        local
 subclasssets
 =
 readarray
(
f
)
1042        local
 rules
        =
 {
 }
1043        if
 subclasssets
 then
1044            coverage
 =
 readcoverage
(
f
,
tableoffset
+
coverage
,
true
)
1045            for
 i
=
1
,
#
subclasssets
 do
1046                local
 offset
 =
 subclasssets
[
i
]
1047                if
 offset
 >
 0
 then
1048                    local
 firstcoverage
 =
 coverage
[
i
]
1049                    local
 rulesoffset
   =
 tableoffset
 +
 offset
1050                    local
 subclassrules
 =
 readarray
(
f
,
rulesoffset
)
1051                    for
 rule
=
1
,
#
subclassrules
 do
1052                        setposition
(
f
,
rulesoffset
 +
 subclassrules
[
rule
]
)
1053                        local
 nofbefore
 =
 readushort
(
f
)
1054                        local
 before
1055                        if
 nofbefore
 >
 0
 then
1056                            before
 =
 {
 }
1057                            for
 i
=
1
,
nofbefore
 do
1058                                before
[
i
]
 =
 {
 readushort
(
f
)
 }
1059                            end
1060                        end
1061                        local
 nofcurrent
 =
 readushort
(
f
)
1062                        local
 current
    =
 {
 {
 firstcoverage
 }
 }
1063                        for
 i
=
2
,
nofcurrent
 do
1064                            current
[
i
]
 =
 {
 readushort
(
f
)
 }
1065                        end
1066                        local
 nofafter
 =
 readushort
(
f
)
1067                        local
 after
1068                        if
 nofafter
 >
 0
 then
1069                            after
 =
 {
 }
1070                            for
 i
=
1
,
nofafter
 do
1071                                after
[
i
]
 =
 {
 readushort
(
f
)
 }
1072                            end
1073                        end
1074                        local
 noflookups
 =
 readushort
(
f
)
1075                        local
 lookups
    =
 readlookuparray
(
f
,
noflookups
,
nofcurrent
)
1076                        rules
[
#
rules
+
1
]
 =
 {
1077                            before
  =
 before
,
1078                            current
 =
 current
,
1079                            after
   =
 after
,
1080                            lookups
 =
 lookups
,
1081                        }
1082                    end
1083                end
1084            end
1085        else
1086            report
(
"
empty subclassset in %a subtype %i
"
,
"
chainedcontext
"
,
subtype
)
1087        end
1088        return
 {
1089            format
 =
 "
glyphs
"
,
1090            rules
  =
 rules
,
1091        }
1092    elseif
 subtype
 =
=
 2
 then
1093        local
 coverage
        =
 readushort
(
f
)
1094        local
 beforeclassdef
  =
 readushort
(
f
)
1095        local
 currentclassdef
 =
 readushort
(
f
)
1096        local
 afterclassdef
   =
 readushort
(
f
)
1097        local
 subclasssets
    =
 readarray
(
f
)
1098        local
 rules
           =
 {
 }
1099        if
 subclasssets
 then
1100            local
 coverage
        =
 readcoverage
(
f
,
tableoffset
 +
 coverage
)
1101            local
 beforeclassdef
  =
 readclassdef
(
f
,
tableoffset
 +
 beforeclassdef
,
nofglyphs
)
1102            local
 currentclassdef
 =
 readclassdef
(
f
,
tableoffset
 +
 currentclassdef
,
coverage
)
1103            local
 afterclassdef
   =
 readclassdef
(
f
,
tableoffset
 +
 afterclassdef
,
nofglyphs
)
1104            local
 beforeclasses
   =
 classtocoverage
(
beforeclassdef
,
fontdata
.
glyphs
)
1105            local
 currentclasses
  =
 classtocoverage
(
currentclassdef
,
fontdata
.
glyphs
)
1106            local
 afterclasses
    =
 classtocoverage
(
afterclassdef
,
fontdata
.
glyphs
)
1107            for
 class
=
1
,
#
subclasssets
 do
1108                local
 offset
 =
 subclasssets
[
class
]
1109                if
 offset
 >
 0
 then
1110                    local
 firstcoverage
 =
 currentclasses
[
class
]
1111                    if
 firstcoverage
 then
1112                        firstcoverage
 =
 covered
(
firstcoverage
,
coverage
)
 -- bonus
1113                        if
 firstcoverage
 then
1114                            local
 rulesoffset
   =
 tableoffset
 +
 offset
1115                            local
 subclassrules
 =
 readarray
(
f
,
rulesoffset
)
1116                            for
 rule
=
1
,
#
subclassrules
 do
1117                                -- watch out, in context we first get the counts and then the arrays while
1118                                -- here we get them mixed
1119                                setposition
(
f
,
rulesoffset
 +
 subclassrules
[
rule
]
)
1120                                local
 nofbefore
 =
 readushort
(
f
)
1121                                local
 before
1122                                if
 nofbefore
 >
 0
 then
1123                                    before
 =
 {
 }
1124                                    for
 i
=
1
,
nofbefore
 do
1125                                        before
[
i
]
 =
 beforeclasses
[
readushort
(
f
)
 +
 1
]
1126                                    end
1127                                end
1128                                local
 nofcurrent
 =
 readushort
(
f
)
1129                                local
 current
    =
 {
 firstcoverage
 }
1130                                for
 i
=
2
,
nofcurrent
 do
1131                                    current
[
i
]
 =
 currentclasses
[
readushort
(
f
)
+
 1
]
1132                                end
1133                                local
 nofafter
 =
 readushort
(
f
)
1134                                local
 after
1135                                if
 nofafter
 >
 0
 then
1136                                    after
 =
 {
 }
1137                                    for
 i
=
1
,
nofafter
 do
1138                                        after
[
i
]
 =
 afterclasses
[
readushort
(
f
)
 +
 1
]
1139                                    end
1140                                end
1141                                -- no sequence index here (so why in context as it saves nothing)
1142                                local
 noflookups
 =
 readushort
(
f
)
1143                                local
 lookups
    =
 readlookuparray
(
f
,
noflookups
,
nofcurrent
)
1144                                rules
[
#
rules
+
1
]
 =
 {
1145                                    before
  =
 before
,
1146                                    current
 =
 current
,
1147                                    after
   =
 after
,
1148                                    lookups
 =
 lookups
,
1149                                }
1150                            end
1151                        else
1152                            report
(
"
no coverage
"
)
1153                        end
1154                    else
1155                        report
(
"
class is not covered
"
)
1156                    end
1157                end
1158            end
1159        else
1160            report
(
"
empty subclassset in %a subtype %i
"
,
"
chainedcontext
"
,
subtype
)
1161        end
1162        return
 {
1163            format
 =
 "
class
"
,
1164            rules
  =
 rules
,
1165        }
1166    elseif
 subtype
 =
=
 3
 then
1167        local
 before
     =
 readarray
(
f
)
1168        local
 current
    =
 readarray
(
f
)
1169        local
 after
      =
 readarray
(
f
)
1170        local
 noflookups
 =
 readushort
(
f
)
1171        local
 lookups
    =
 readlookuparray
(
f
,
noflookups
,
#
current
)
1172        before
  =
 readcoveragearray
(
f
,
tableoffset
,
before
,
true
)
1173        current
 =
 readcoveragearray
(
f
,
tableoffset
,
current
,
true
)
1174        after
   =
 readcoveragearray
(
f
,
tableoffset
,
after
,
true
)
1175        return
 {
1176            format
 =
 "
coverage
"
,
1177            rules
  =
 {
1178                {
1179                    before
  =
 before
,
1180                    current
 =
 current
,
1181                    after
   =
 after
,
1182                    lookups
 =
 lookups
,
1183                }
1184            }
1185        }
1186    else
1187        report
(
"
unsupported subtype %a in %a %s
"
,
subtype
,
"
chainedcontext
"
,
what
)
1188    end
1189end
1190
1191local
 function
 extension
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
types
,
handlers
,
what
)
1192    local
 tableoffset
 =
 lookupoffset
 +
 offset
1193    setposition
(
f
,
tableoffset
)
1194    local
 subtype
 =
 readushort
(
f
)
1195    if
 subtype
 =
=
 1
 then
1196        local
 lookuptype
 =
 types
[
readushort
(
f
)
]
1197        local
 faroffset
  =
 readulong
(
f
)
1198        local
 handler
    =
 handlers
[
lookuptype
]
1199        if
 handler
 then
1200            -- maybe we can just pass one offset (or tableoffset first)
1201            return
 handler
(
f
,
fontdata
,
lookupid
,
tableoffset
 +
 faroffset
,
0
,
glyphs
,
nofglyphs
)
,
 lookuptype
1202        else
1203            report
(
"
no handler for lookuptype %a subtype %a in %s %s
"
,
lookuptype
,
subtype
,
what
,
"
extension
"
)
1204        end
1205    else
1206        report
(
"
unsupported subtype %a in %s %s
"
,
subtype
,
what
,
"
extension
"
)
1207    end
1208end
1209
1210-- gsub handlers
1211
1212function
 gsubhandlers
.
single
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1213    local
 tableoffset
 =
 lookupoffset
 +
 offset
1214    setposition
(
f
,
tableoffset
)
1215    local
 subtype
 =
 readushort
(
f
)
1216    if
 subtype
 =
=
 1
 then
1217        local
 coverage
 =
 readushort
(
f
)
1218        local
 delta
    =
 readshort
(
f
)
 -- can be negative
1219        local
 coverage
 =
 readcoverage
(
f
,
tableoffset
+
coverage
)
 -- not simple as we need to set key/value anyway
1220        for
 index
 in
 next
,
 coverage
 do
1221            local
 newindex
 =
 (
index
 +
 delta
)
 %
 65536
 -- modulo is new in 1.8.3
1222            if
 index
 >
 nofglyphs
 or
 newindex
 >
 nofglyphs
 then
1223                report
(
"
invalid index in %s format %i: %i -> %i (max %i)
"
,
"
single
"
,
subtype
,
index
,
newindex
,
nofglyphs
)
1224                coverage
[
index
]
 =
 nil
1225            else
1226                coverage
[
index
]
 =
 newindex
1227            end
1228        end
1229        return
 {
1230            coverage
 =
 coverage
1231        }
1232    elseif
 subtype
 =
=
 2
 then
 -- in streamreader a seek and fetch is faster than a temp table
1233        local
 coverage
        =
 readushort
(
f
)
1234        local
 nofreplacements
 =
 readushort
(
f
)
1235        local
 replacements
    =
 readcardinaltable
(
f
,
nofreplacements
,
ushort
)
1236        local
 coverage
 =
 readcoverage
(
f
,
tableoffset
 +
 coverage
)
 -- not simple as we need to set key/value anyway
1237        for
 index
,
 newindex
 in
 next
,
 coverage
 do
1238            newindex
 =
 newindex
 +
 1
1239            if
 index
 >
 nofglyphs
 or
 newindex
 >
 nofglyphs
 then
1240                report
(
"
invalid index in %s format %i: %i -> %i (max %i)
"
,
"
single
"
,
subtype
,
index
,
newindex
,
nofglyphs
)
1241                coverage
[
index
]
 =
 nil
1242            else
1243                coverage
[
index
]
 =
 replacements
[
newindex
]
1244            end
1245        end
1246        return
 {
1247            coverage
 =
 coverage
1248        }
1249    else
1250        report
(
"
unsupported subtype %a in %a substitution
"
,
subtype
,
"
single
"
)
1251    end
1252end
1253
1254-- we see coverage format 0x300 in some old ms fonts
1255
1256local
 function
 sethandler
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
what
)
1257    local
 tableoffset
 =
 lookupoffset
 +
 offset
1258    setposition
(
f
,
tableoffset
)
1259    local
 subtype
 =
 readushort
(
f
)
1260    if
 subtype
 =
=
 1
 then
1261        local
 coverage
    =
 readushort
(
f
)
1262        local
 nofsequence
 =
 readushort
(
f
)
1263        local
 sequences
   =
 readcardinaltable
(
f
,
nofsequence
,
ushort
)
1264        for
 i
=
1
,
nofsequence
 do
1265            setposition
(
f
,
tableoffset
 +
 sequences
[
i
]
)
1266            sequences
[
i
]
 =
 readcardinaltable
(
f
,
readushort
(
f
)
,
ushort
)
1267        end
1268        local
 coverage
 =
 readcoverage
(
f
,
tableoffset
 +
 coverage
)
1269        for
 index
,
 newindex
 in
 next
,
 coverage
 do
1270            newindex
 =
 newindex
 +
 1
1271            if
 index
 >
 nofglyphs
 or
 newindex
 >
 nofglyphs
 then
1272                report
(
"
invalid index in %s format %i: %i -> %i (max %i)
"
,
what
,
subtype
,
index
,
newindex
,
nofglyphs
)
1273                coverage
[
index
]
 =
 nil
1274            else
1275                coverage
[
index
]
 =
 sequences
[
newindex
]
1276            end
1277        end
1278        return
 {
1279            coverage
 =
 coverage
1280        }
1281    else
1282        report
(
"
unsupported subtype %a in %a substitution
"
,
subtype
,
what
)
1283    end
1284end
1285
1286function
 gsubhandlers
.
multiple
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1287    return
 sethandler
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
"
multiple
"
)
1288end
1289
1290function
 gsubhandlers
.
alternate
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1291    return
 sethandler
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
"
alternate
"
)
1292end
1293
1294function
 gsubhandlers
.
ligature
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1295    local
 tableoffset
 =
 lookupoffset
 +
 offset
1296    setposition
(
f
,
tableoffset
)
1297    local
 subtype
 =
 readushort
(
f
)
1298    if
 subtype
 =
=
 1
 then
1299        local
 coverage
  =
 readushort
(
f
)
1300        local
 nofsets
   =
 readushort
(
f
)
1301        local
 ligatures
 =
 readcardinaltable
(
f
,
nofsets
,
ushort
)
1302        for
 i
=
1
,
nofsets
 do
1303            local
 offset
 =
 lookupoffset
 +
 offset
 +
 ligatures
[
i
]
1304            setposition
(
f
,
offset
)
1305            local
 n
 =
 readushort
(
f
)
1306            if
 n
 =
=
 1
 then
1307                ligatures
[
i
]
 =
 {
 offset
 +
 readushort
(
f
)
 }
1308            else
1309                local
 l
 =
 {
 }
1310                for
 i
=
1
,
n
 do
1311                    l
[
i
]
 =
 offset
 +
 readushort
(
f
)
1312                end
1313                ligatures
[
i
]
 =
 l
1314            end
1315        end
1316        local
 coverage
 =
 readcoverage
(
f
,
tableoffset
 +
 coverage
)
1317        for
 index
,
 newindex
 in
 next
,
 coverage
 do
1318            local
 hash
 =
 {
 }
1319            local
 ligatures
 =
 ligatures
[
newindex
+
1
]
1320            for
 i
=
1
,
#
ligatures
 do
1321                local
 offset
 =
 ligatures
[
i
]
1322                setposition
(
f
,
offset
)
1323                local
 lig
 =
 readushort
(
f
)
1324                local
 cnt
 =
 readushort
(
f
)
1325                local
 hsh
 =
 hash
1326                for
 i
=
2
,
cnt
 do
1327                    local
 c
 =
 readushort
(
f
)
1328                    local
 h
 =
 hsh
[
c
]
1329                    if
 not
 h
 then
1330                        h
 =
 {
 }
1331                        hsh
[
c
]
 =
 h
1332                    end
1333                    hsh
 =
  h
1334                end
1335                hsh
.
ligature
 =
 lig
1336            end
1337            coverage
[
index
]
 =
 hash
1338        end
1339        return
 {
1340            coverage
 =
 coverage
1341        }
1342    else
1343        report
(
"
unsupported subtype %a in %a substitution
"
,
subtype
,
"
ligature
"
)
1344    end
1345end
1346
1347function
 gsubhandlers
.
context
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1348    return
 unchainedcontext
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
"
substitution
"
)
,
 "
context
"
1349end
1350
1351function
 gsubhandlers
.
chainedcontext
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1352    return
 chainedcontext
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
"
substitution
"
)
,
 "
chainedcontext
"
1353end
1354
1355function
 gsubhandlers
.
extension
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1356    return
 extension
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
gsubtypes
,
gsubhandlers
,
"
substitution
"
)
1357end
1358
1359function
 gsubhandlers
.
reversechainedcontextsingle
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1360    local
 tableoffset
 =
 lookupoffset
 +
 offset
1361    setposition
(
f
,
tableoffset
)
1362    local
 subtype
 =
 readushort
(
f
)
1363    if
 subtype
 =
=
 1
 then
 -- NEEDS CHECKING
1364        local
 current
      =
 readfirst
(
f
)
1365        local
 before
       =
 readarray
(
f
)
1366        local
 after
        =
 readarray
(
f
)
1367        local
 replacements
 =
 readarray
(
f
)
1368        current
 =
 readcoveragearray
(
f
,
tableoffset
,
current
,
true
)
1369        before
  =
 readcoveragearray
(
f
,
tableoffset
,
before
,
true
)
1370        after
   =
 readcoveragearray
(
f
,
tableoffset
,
after
,
true
)
1371        return
 {
1372            format
 =
 "
reversecoverage
"
,
 -- reversesub
1373            rules
  =
 {
1374                {
1375                    before
       =
 before
,
1376                    current
      =
 current
,
1377                    after
        =
 after
,
1378                    replacements
 =
 replacements
,
1379                }
1380            }
1381        }
,
 "
reversechainedcontextsingle
"
1382    else
1383        report
(
"
unsupported subtype %a in %a substitution
"
,
subtype
,
"
reversechainedcontextsingle
"
)
1384    end
1385end
1386
1387-- gpos handlers
1388
1389local
 function
 readpairsets
(
f
,
tableoffset
,
sets
,
format1
,
format2
,
mainoffset
,
getdelta
)
1390    local
 done
 =
 {
 }
1391    for
 i
=
1
,
#
sets
 do
1392        local
 offset
 =
 sets
[
i
]
1393        local
 reused
 =
 done
[
offset
]
1394        if
 not
 reused
 then
1395            offset
 =
 tableoffset
 +
 offset
1396            setposition
(
f
,
offset
)
1397            local
 n
 =
 readushort
(
f
)
1398            reused
 =
 {
 }
1399            for
 i
=
1
,
n
 do
1400                reused
[
i
]
 =
 {
1401                    readushort
(
f
)
,
 -- second glyph id
1402                    readposition
(
f
,
format1
,
offset
,
getdelta
)
,
1403                    readposition
(
f
,
format2
,
offset
,
getdelta
)
,
1404                }
1405            end
1406            done
[
offset
]
 =
 reused
1407        end
1408        sets
[
i
]
 =
 reused
1409    end
1410    return
 sets
1411end
1412
1413local
 function
 readpairclasssets
(
f
,
nofclasses1
,
nofclasses2
,
format1
,
format2
,
mainoffset
,
getdelta
)
1414    local
 classlist1
  =
 {
 }
1415    for
 i
=
1
,
nofclasses1
 do
1416        local
 classlist2
 =
 {
 }
1417        classlist1
[
i
]
 =
 classlist2
1418        for
 j
=
1
,
nofclasses2
 do
1419            local
 one
 =
 readposition
(
f
,
format1
,
mainoffset
,
getdelta
)
1420            local
 two
 =
 readposition
(
f
,
format2
,
mainoffset
,
getdelta
)
1421            if
 one
 or
 two
 then
1422                classlist2
[
j
]
 =
 {
 one
,
 two
 }
1423            else
1424                classlist2
[
j
]
 =
 false
1425            end
1426        end
1427    end
1428    return
 classlist1
1429end
1430
1431-- no real gain in kerns as we pack
1432
1433function
 gposhandlers
.
single
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1434    local
 tableoffset
 =
 lookupoffset
 +
 offset
1435    setposition
(
f
,
tableoffset
)
1436    local
 subtype
  =
 readushort
(
f
)
1437    local
 getdelta
 =
 fontdata
.
temporary
.
getdelta
1438    if
 subtype
 =
=
 1
 then
1439        local
 coverage
 =
 readushort
(
f
)
1440        local
 format
   =
 readushort
(
f
)
1441        local
 value
    =
 readposition
(
f
,
format
,
tableoffset
,
getdelta
)
1442        local
 coverage
 =
 readcoverage
(
f
,
tableoffset
+
coverage
)
1443        for
 index
,
 newindex
 in
 next
,
 coverage
 do
1444            coverage
[
index
]
 =
 value
 -- will be packed and shared anyway
1445        end
1446        return
 {
1447            format
   =
 "
single
"
,
1448            coverage
 =
 coverage
,
1449        }
1450    elseif
 subtype
 =
=
 2
 then
1451        local
 coverage
  =
 readushort
(
f
)
1452        local
 format
    =
 readushort
(
f
)
1453        local
 nofvalues
 =
 readushort
(
f
)
1454        local
 values
    =
 {
 }
1455        for
 i
=
1
,
nofvalues
 do
1456            values
[
i
]
 =
 readposition
(
f
,
format
,
tableoffset
,
getdelta
)
1457        end
1458        local
 coverage
 =
 readcoverage
(
f
,
tableoffset
+
coverage
)
1459        for
 index
,
 newindex
 in
 next
,
 coverage
 do
1460            coverage
[
index
]
 =
 values
[
newindex
+
1
]
1461        end
1462        return
 {
1463            format
   =
 "
single
"
,
1464            coverage
 =
 coverage
,
1465        }
1466    else
1467        report
(
"
unsupported subtype %a in %a positioning
"
,
subtype
,
"
single
"
)
1468    end
1469end
1470
1471-- this needs checking! if no second pair then another advance over the list
1472
1473-- ValueFormat1 applies to the ValueRecord of the first glyph in each pair. ValueRecords for all first glyphs must use ValueFormat1. If ValueFormat1 is set to zero (0), the corresponding glyph has no ValueRecord and, therefore, should not be repositioned.
1474-- ValueFormat2 applies to the ValueRecord of the second glyph in each pair. ValueRecords for all second glyphs must use ValueFormat2. If ValueFormat2 is set to null, then the second glyph of the pair is the “next” glyph for which a lookup should be performed.
1475
1476-- local simple = {
1477--     [true]  = { [true] = { true,  true }, [false] = { true  } },
1478--     [false] = { [true] = { false, true }, [false] = { false } },
1479-- }
1480
1481-- function gposhandlers.pair(f,fontdata,lookupid,lookupoffset,offset,glyphs,nofglyphs)
1482--     local tableoffset = lookupoffset + offset
1483--     setposition(f,tableoffset)
1484--     local subtype  = readushort(f)
1485--     local getdelta = fontdata.temporary.getdelta
1486--     if subtype == 1 then
1487--         local coverage = readushort(f)
1488--         local format1  = readushort(f)
1489--         local format2  = readushort(f)
1490--         local sets     = readarray(f)
1491--               sets     = readpairsets(f,tableoffset,sets,format1,format2,mainoffset,getdelta)
1492--               coverage = readcoverage(f,tableoffset + coverage)
1493--         local shared   = { } -- partial sparse, when set also needs to be handled in the packer
1494--         for index, newindex in next, coverage do
1495--             local set  = sets[newindex+1]
1496--             local hash = { }
1497--             for i=1,#set do
1498--                 local value = set[i]
1499--                 if value then
1500--                     local other  = value[1]
1501--                     if shared then
1502--                         local s = shared[value]
1503--                         if s == nil then
1504--                             local first  = value[2]
1505--                             local second = value[3]
1506--                             if first or second then
1507--                                 s = { first, second or nil } -- needs checking
1508--                             else
1509--                                 s = false
1510--                             end
1511--                             shared[value] = s
1512--                         end
1513--                         hash[other] = s or nil
1514--                     else
1515--                         local first  = value[2]
1516--                         local second = value[3]
1517--                         if first or second then
1518--                             hash[other] = { first, second or nil } -- needs checking
1519--                         else
1520--                             hash[other] = nil -- what if set, maybe warning
1521--                         end
1522--                     end
1523--                 end
1524--             end
1525--             coverage[index] = hash
1526--         end
1527--         return {
1528--             shared   = shared and true or nil,
1529--             format   = "pair",
1530--             coverage = coverage,
1531--         }
1532--     elseif subtype == 2 then
1533--         local coverage     = readushort(f)
1534--         local format1      = readushort(f)
1535--         local format2      = readushort(f)
1536--         local classdef1    = readushort(f)
1537--         local classdef2    = readushort(f)
1538--         local nofclasses1  = readushort(f) -- incl class 0
1539--         local nofclasses2  = readushort(f) -- incl class 0
1540--         local classlist    = readpairclasssets(f,nofclasses1,nofclasses2,format1,format2,tableoffset,getdelta)
1541--               coverage     = readcoverage(f,tableoffset+coverage)
1542--               classdef1    = readclassdef(f,tableoffset+classdef1,coverage)
1543--               classdef2    = readclassdef(f,tableoffset+classdef2,nofglyphs)
1544--         local usedcoverage = { }
1545--         local shared       = { } -- partial sparse, when set also needs to be handled in the packer
1546--         for g1, c1 in next, classdef1 do
1547--             if coverage[g1] then
1548--                 local l1 = classlist[c1]
1549--                 if l1 then
1550--                     local hash = { }
1551--                     for paired, class in next, classdef2 do
1552--                         local offsets = l1[class]
1553--                         if offsets then
1554--                             local first  = offsets[1]
1555--                             local second = offsets[2]
1556--                             if first or second then
1557--                                 if shared then
1558--                                     local s1 = shared[first]
1559--                                     if s1 == nil then
1560--                                         s1 = { }
1561--                                         shared[first] = s1
1562--                                     end
1563--                                     local s2 = s1[second]
1564--                                     if s2 == nil then
1565--                                         s2 = { first, second or nil }
1566--                                         s1[second] = s2
1567--                                     end
1568--                                     hash[paired] = s2
1569--                                 else
1570--                                     hash[paired] = { first, second or nil }
1571--                                 end
1572--                             else
1573--                                 -- upto the next lookup for this combination
1574--                             end
1575--                         end
1576--                     end
1577--                     usedcoverage[g1] = hash
1578--                 end
1579--             end
1580--         end
1581--         return {
1582--             shared   = shared and true or nil,
1583--             format   = "pair",
1584--             coverage = usedcoverage,
1585--         }
1586--     elseif subtype == 3 then
1587--         report("yet unsupported subtype %a in %a positioning",subtype,"pair")
1588--     else
1589--         report("unsupported subtype %a in %a positioning",subtype,"pair")
1590--     end
1591-- end
1592
1593function
 gposhandlers
.
pair
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1594    local
 tableoffset
 =
 lookupoffset
 +
 offset
1595    setposition
(
f
,
tableoffset
)
1596    local
 subtype
  =
 readushort
(
f
)
1597    local
 getdelta
 =
 fontdata
.
temporary
.
getdelta
1598    if
 subtype
 =
=
 1
 then
1599        local
 coverage
 =
 readushort
(
f
)
1600        local
 format1
  =
 readushort
(
f
)
1601        local
 format2
  =
 readushort
(
f
)
1602        local
 sets
     =
 readarray
(
f
)
1603              sets
     =
 readpairsets
(
f
,
tableoffset
,
sets
,
format1
,
format2
,
mainoffset
,
getdelta
)
1604              coverage
 =
 readcoverage
(
f
,
tableoffset
 +
 coverage
)
1605        local
 shared
   =
 {
 }
 -- partial sparse, when set also needs to be handled in the packer
1606        for
 index
,
 newindex
 in
 next
,
 coverage
 do
1607            local
 set
  =
 sets
[
newindex
+
1
]
1608            local
 hash
 =
 {
 }
1609            for
 i
=
1
,
#
set
 do
1610                local
 value
 =
 set
[
i
]
1611                if
 value
 then
1612                    local
 other
 =
 value
[
1
]
1613                    local
 share
 =
 shared
[
value
]
1614                    if
 share
 =
=
 nil
 then
1615                        local
 first
  =
 value
[
2
]
1616                        local
 second
 =
 value
[
3
]
1617                        if
 first
 or
 second
 then
1618                            share
 =
 {
 first
,
 second
 or
 nil
 }
 -- needs checking
1619                        else
1620                            share
 =
 false
1621                        end
1622                        shared
[
value
]
 =
 share
1623                    end
1624                    hash
[
other
]
 =
 share
 or
 nil
 -- really overload ?
1625                end
1626            end
1627            coverage
[
index
]
 =
 hash
1628        end
1629        return
 {
1630            shared
   =
 shared
 and
 true
 or
 nil
,
1631            format
   =
 "
pair
"
,
1632            coverage
 =
 coverage
,
1633        }
1634    elseif
 subtype
 =
=
 2
 then
1635        local
 coverage
     =
 readushort
(
f
)
1636        local
 format1
      =
 readushort
(
f
)
1637        local
 format2
      =
 readushort
(
f
)
1638        local
 classdef1
    =
 readushort
(
f
)
1639        local
 classdef2
    =
 readushort
(
f
)
1640        local
 nofclasses1
  =
 readushort
(
f
)
 -- incl class 0
1641        local
 nofclasses2
  =
 readushort
(
f
)
 -- incl class 0
1642        local
 classlist
    =
 readpairclasssets
(
f
,
nofclasses1
,
nofclasses2
,
format1
,
format2
,
tableoffset
,
getdelta
)
1643              coverage
     =
 readcoverage
(
f
,
tableoffset
+
coverage
)
1644              classdef1
    =
 readclassdef
(
f
,
tableoffset
+
classdef1
,
coverage
)
1645              classdef2
    =
 readclassdef
(
f
,
tableoffset
+
classdef2
,
nofglyphs
)
1646        local
 usedcoverage
 =
 {
 }
1647        local
 shared
       =
 {
 }
 -- partial sparse, when set also needs to be handled in the packer
1648        for
 g1
,
 c1
 in
 next
,
 classdef1
 do
1649            if
 coverage
[
g1
]
 then
1650                local
 l1
 =
 classlist
[
c1
]
1651                if
 l1
 then
1652                    local
 hash
 =
 {
 }
1653                    for
 paired
,
 class
 in
 next
,
 classdef2
 do
1654                        local
 offsets
 =
 l1
[
class
]
1655                        if
 offsets
 then
1656                            local
 first
  =
 offsets
[
1
]
1657                            local
 second
 =
 offsets
[
2
]
1658                            if
 first
 or
 second
 then
1659                                local
 s1
 =
 shared
[
first
]
1660                                if
 s1
 =
=
 nil
 then
1661                                    s1
 =
 {
 }
1662                                    shared
[
first
]
 =
 s1
1663                                end
1664                                local
 s2
 =
 s1
[
second
]
1665                                if
 s2
 =
=
 nil
 then
1666                                    s2
 =
 {
 first
,
 second
 or
 nil
 }
1667                                    s1
[
second
]
 =
 s2
1668                                end
1669                                hash
[
paired
]
 =
 s2
1670                            end
1671                        end
1672                    end
1673                    usedcoverage
[
g1
]
 =
 hash
1674                end
1675            end
1676        end
1677        return
 {
1678            shared
   =
 shared
 and
 true
 or
 nil
,
1679            format
   =
 "
pair
"
,
1680            coverage
 =
 usedcoverage
,
1681        }
1682    elseif
 subtype
 =
=
 3
 then
1683        report
(
"
yet unsupported subtype %a in %a positioning
"
,
subtype
,
"
pair
"
)
1684    else
1685        report
(
"
unsupported subtype %a in %a positioning
"
,
subtype
,
"
pair
"
)
1686    end
1687end
1688
1689function
 gposhandlers
.
cursive
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1690    local
 tableoffset
 =
 lookupoffset
 +
 offset
1691    setposition
(
f
,
tableoffset
)
1692    local
 subtype
  =
 readushort
(
f
)
1693    local
 getdelta
 =
 fontdata
.
temporary
.
getdelta
1694    if
 subtype
 =
=
 1
 then
1695        local
 coverage
   =
 tableoffset
 +
 readushort
(
f
)
1696        local
 nofrecords
 =
 readushort
(
f
)
1697        local
 records
    =
 {
 }
1698        for
 i
=
1
,
nofrecords
 do
1699            local
 entry
 =
 readushort
(
f
)
1700            local
 exit
  =
 readushort
(
f
)
1701            records
[
i
]
 =
 {
1702             -- entry = entry ~= 0 and (tableoffset + entry) or false,
1703             -- exit  = exit  ~= 0 and (tableoffset + exit ) or nil,
1704                entry
 ~
=
 0
 and
 (
tableoffset
 +
 entry
)
 or
 false
,
1705                exit
  ~
=
 0
 and
 (
tableoffset
 +
 exit
 )
 or
 nil
,
1706            }
1707        end
1708        -- slot 1 will become hash after loading and it must be unique because we
1709        -- pack the tables (packed we turn the cc-* into a zero)
1710        local
 cc
 =
 (
fontdata
.
temporary
.
cursivecount
 or
 0
)
 +
 1
1711        fontdata
.
temporary
.
cursivecount
 =
 cc
1712        cc
 =
 "
cc-
"
 .
.
 cc
1713        coverage
 =
 readcoverage
(
f
,
coverage
)
1714        for
 i
=
1
,
nofrecords
 do
1715            local
 r
 =
 records
[
i
]
1716            records
[
i
]
 =
 {
1717             -- 1,
1718                cc
,
1719             -- readanchor(f,r.entry,getdelta) or false,
1720             -- readanchor(f,r.exit, getdelta) or nil,
1721                readanchor
(
f
,
r
[
1
]
,
getdelta
)
 or
 false
,
1722                readanchor
(
f
,
r
[
2
]
,
getdelta
)
 or
 nil
,
1723            }
1724        end
1725        for
 index
,
 newindex
 in
 next
,
 coverage
 do
1726            coverage
[
index
]
 =
 records
[
newindex
+
1
]
1727        end
1728        return
 {
1729            coverage
 =
 coverage
,
1730        }
1731    else
1732        report
(
"
unsupported subtype %a in %a positioning
"
,
subtype
,
"
cursive
"
)
1733    end
1734end
1735
1736local
 function
 handlemark
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
ligature
)
1737    local
 tableoffset
 =
 lookupoffset
 +
 offset
1738    setposition
(
f
,
tableoffset
)
1739    local
 subtype
  =
 readushort
(
f
)
1740    local
 getdelta
 =
 fontdata
.
temporary
.
getdelta
1741    if
 subtype
 =
=
 1
 then
1742        -- we are one based, not zero
1743        local
 markcoverage
 =
 tableoffset
 +
 readushort
(
f
)
1744        local
 basecoverage
 =
 tableoffset
 +
 readushort
(
f
)
1745        local
 nofclasses
   =
 readushort
(
f
)
1746        local
 markoffset
   =
 tableoffset
 +
 readushort
(
f
)
1747        local
 baseoffset
   =
 tableoffset
 +
 readushort
(
f
)
1748        --
1749        local
 markcoverage
 =
 readcoverage
(
f
,
markcoverage
)
1750        local
 basecoverage
 =
 readcoverage
(
f
,
basecoverage
,
true
)
 -- TO BE CHECKED: true
1751        --
1752        setposition
(
f
,
markoffset
)
1753        local
 markclasses
    =
 {
 }
1754        local
 nofmarkclasses
 =
 readushort
(
f
)
1755        --
1756        local
 lastanchor
  =
 fontdata
.
lastanchor
 or
 0
1757        local
 usedanchors
 =
 {
 }
1758        --
1759        for
 i
=
1
,
nofmarkclasses
 do
1760            local
 class
  =
 readushort
(
f
)
 +
 1
1761            local
 offset
 =
 readushort
(
f
)
1762            if
 offset
 =
=
 0
 then
1763                markclasses
[
i
]
 =
 false
1764            else
1765                markclasses
[
i
]
 =
 {
 class
,
 markoffset
 +
 offset
 }
1766            end
1767            usedanchors
[
class
]
 =
 true
1768        end
1769        for
 i
=
1
,
nofmarkclasses
 do
1770            local
 mc
 =
 markclasses
[
i
]
1771            if
 mc
 then
1772                mc
[
2
]
 =
 readanchor
(
f
,
mc
[
2
]
,
getdelta
)
1773            end
1774        end
1775        --
1776        setposition
(
f
,
baseoffset
)
1777        local
 nofbaserecords
 =
 readushort
(
f
)
1778        local
 baserecords
    =
 {
 }
1779        --
1780        if
 ligature
 then
1781            -- 3 components
1782            -- 1 : class .. nofclasses -- NULL when empty
1783            -- 2 : class .. nofclasses -- NULL when empty
1784            -- 3 : class .. nofclasses -- NULL when empty
1785            for
 i
=
1
,
nofbaserecords
 do
 -- here i is the class
1786                local
 offset
 =
 readushort
(
f
)
1787                if
 offset
 =
=
 0
 then
1788                    baserecords
[
i
]
 =
 false
1789                else
1790                    baserecords
[
i
]
 =
 baseoffset
 +
 offset
1791                end
1792            end
1793            for
 i
=
1
,
nofbaserecords
 do
1794                local
 recordoffset
 =
 baserecords
[
i
]
1795                if
 recordoffset
 then
1796                    setposition
(
f
,
recordoffset
)
1797                    local
 nofcomponents
 =
 readushort
(
f
)
1798                    local
 components
 =
 {
 }
1799                    for
 i
=
1
,
nofcomponents
 do
1800                        local
 classes
 =
 {
 }
1801                        for
 i
=
1
,
nofclasses
 do
1802                            local
 offset
 =
 readushort
(
f
)
1803                            if
 offset
 ~
=
 0
 then
1804                                classes
[
i
]
 =
 recordoffset
 +
 offset
1805                            else
1806                                classes
[
i
]
 =
 false
1807                            end
1808                        end
1809                        components
[
i
]
 =
 classes
1810                    end
1811                    baserecords
[
i
]
 =
 components
1812                end
1813            end
1814            local
 baseclasses
 =
 {
 }
 -- setmetatableindex("table")
1815            for
 i
=
1
,
nofclasses
 do
1816                baseclasses
[
i
]
 =
 {
 }
1817            end
1818            for
 i
=
1
,
nofbaserecords
 do
1819                local
 components
 =
 baserecords
[
i
]
1820                if
 components
 then
1821                    local
 b
 =
 basecoverage
[
i
]
1822                    for
 c
=
1
,
#
components
 do
1823                        local
 classes
 =
 components
[
c
]
1824                        if
 classes
 then
1825                            for
 i
=
1
,
nofclasses
 do
1826                                local
 anchor
 =
 readanchor
(
f
,
classes
[
i
]
,
getdelta
)
1827                                local
 bclass
 =
 baseclasses
[
i
]
1828                                local
 bentry
 =
 bclass
[
b
]
1829                                if
 bentry
 then
1830                                    bentry
[
c
]
 =
 anchor
1831                                else
1832                                    bclass
[
b
]
=
 {
 [
c
]
 =
 anchor
 }
1833                                end
1834                            end
1835                        end
1836                    end
1837                end
1838            end
1839            for
 index
,
 newindex
 in
 next
,
 markcoverage
 do
1840                markcoverage
[
index
]
 =
 markclasses
[
newindex
+
1
]
 or
 nil
1841            end
1842            return
 {
1843                format
      =
 "
ligature
"
,
1844                baseclasses
 =
 baseclasses
,
1845                coverage
    =
 markcoverage
,
1846            }
1847        else
1848            for
 i
=
1
,
nofbaserecords
 do
1849                local
 r
 =
 {
 }
1850                for
 j
=
1
,
nofclasses
 do
1851                    local
 offset
 =
 readushort
(
f
)
1852                    if
 offset
 =
=
 0
 then
1853                        r
[
j
]
 =
 false
1854                    else
1855                        r
[
j
]
 =
 baseoffset
 +
 offset
1856                    end
1857                end
1858                baserecords
[
i
]
 =
 r
1859            end
1860            local
 baseclasses
 =
 {
 }
 -- setmetatableindex("table")
1861            for
 i
=
1
,
nofclasses
 do
1862                baseclasses
[
i
]
 =
 {
 }
1863            end
1864            for
 i
=
1
,
nofbaserecords
 do
1865                local
 r
 =
 baserecords
[
i
]
1866                local
 b
 =
 basecoverage
[
i
]
1867                for
 j
=
1
,
nofclasses
 do
1868                    baseclasses
[
j
]
[
b
]
 =
 readanchor
(
f
,
r
[
j
]
,
getdelta
)
1869                end
1870            end
1871            for
 index
,
 newindex
 in
 next
,
 markcoverage
 do
1872                markcoverage
[
index
]
 =
 markclasses
[
newindex
+
1
]
 or
 nil
1873            end
1874            -- we could actually already calculate the displacement if we want
1875            return
 {
1876                format
      =
 "
base
"
,
1877                baseclasses
 =
 baseclasses
,
1878                coverage
    =
 markcoverage
,
1879            }
1880        end
1881    else
1882        report
(
"
unsupported subtype %a in
"
,
subtype
)
1883    end
1884
1885end
1886
1887function
 gposhandlers
.
marktobase
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1888    return
 handlemark
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1889end
1890
1891function
 gposhandlers
.
marktoligature
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1892    return
 handlemark
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
true
)
1893end
1894
1895function
 gposhandlers
.
marktomark
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1896    return
 handlemark
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1897end
1898
1899function
 gposhandlers
.
context
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1900    return
 unchainedcontext
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
"
positioning
"
)
,
 "
context
"
1901end
1902
1903function
 gposhandlers
.
chainedcontext
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1904    return
 chainedcontext
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
"
positioning
"
)
,
 "
chainedcontext
"
1905end
1906
1907function
 gposhandlers
.
extension
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
)
1908    return
 extension
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
offset
,
glyphs
,
nofglyphs
,
gpostypes
,
gposhandlers
,
"
positioning
"
)
1909end
1910
1911-- main loader
1912
1913do
1914
1915    local
 plugins
 =
 {
 }
1916
1917    function
 plugins
.
size
(
f
,
fontdata
,
tableoffset
,
feature
)
1918        if
 fontdata
.
designsize
 then
1919            -- yes, there are fonts with multiple size entries ... it probably relates
1920            -- to the other two fields (menu entries in some language)
1921        else
1922            local
 function
 check
(
offset
)
1923                setposition
(
f
,
offset
)
1924                local
 designsize
 =
 readushort
(
f
)
1925                if
 designsize
 >
 0
 then
 -- we could also have a threshold
1926                    local
 fontstyleid
 =
 readushort
(
f
)
1927                    local
 guimenuid
   =
 readushort
(
f
)
1928                    local
 minsize
     =
 readushort
(
f
)
1929                    local
 maxsize
     =
 readushort
(
f
)
1930                    if
 minsize
 =
=
 0
 and
 maxsize
 =
=
 0
 and
 fontstyleid
 =
=
 0
 and
 guimenuid
 =
=
 0
 then
1931                        minsize
 =
 designsize
1932                        maxsize
 =
 designsize
1933                    end
1934                    if
 designsize
 >
=
 minsize
 and
 designsize
 <
=
 maxsize
 then
1935                        return
 minsize
,
 maxsize
,
 designsize
1936                    end
1937                end
1938            end
1939            local
 minsize
,
 maxsize
,
 designsize
 =
 check
(
tableoffset
+
feature
.
offset
+
feature
.
parameters
)
1940            if
 not
 designsize
 then
1941                -- some old adobe fonts have: tableoffset+feature.parameters and we could
1942                -- use some heuristic but why bother ... this extra check will be removed
1943                -- some day and/or when we run into an issue
1944                minsize
,
 maxsize
,
 designsize
 =
 check
(
tableoffset
+
feature
.
parameters
)
1945                if
 designsize
 then
1946                    report
(
"
bad size feature in %a, falling back to wrong offset
"
,
fontdata
.
filename
 or
 "
?
"
)
1947                else
1948                    report
(
"
bad size feature in %a,
"
,
fontdata
.
filename
 or
 "
?
"
)
1949                end
1950            end
1951            if
 designsize
 then
1952                fontdata
.
minsize
    =
 minsize
1953                fontdata
.
maxsize
    =
 maxsize
1954                fontdata
.
designsize
 =
 designsize
1955            end
1956        end
1957    end
1958
1959 -- function plugins.rvrn(f,fontdata,tableoffset,feature)
1960 --     -- todo, at least a message
1961 -- end
1962
1963    -- feature order needs checking ... as we loop over a hash ... however, in the file
1964    -- they are sorted so order is not that relevant
1965
1966    local
 function
 reorderfeatures
(
fontdata
,
scripts
,
features
)
1967        local
 scriptlangs
  =
 {
 }
1968        local
 featurehash
  =
 {
 }
1969        local
 featureorder
 =
 {
 }
1970        for
 script
,
 languages
 in
 next
,
 scripts
 do
1971            for
 language
,
 record
 in
 next
,
 languages
 do
1972                local
 hash
 =
 {
 }
1973                local
 list
 =
 record
.
featureindices
1974                for
 k
=
1
,
#
list
 do
1975                    local
 index
   =
 list
[
k
]
1976                    local
 feature
 =
 features
[
index
]
1977                    local
 lookups
 =
 feature
.
lookups
1978                    local
 tag
     =
 feature
.
tag
1979                    if
 tag
 then
1980                        hash
[
tag
]
 =
 true
1981                    end
1982                    if
 lookups
 then
1983                        for
 i
=
1
,
#
lookups
 do
1984                            local
 lookup
 =
 lookups
[
i
]
1985                            local
 o
 =
 featureorder
[
lookup
]
1986                            if
 o
 then
1987                                local
 okay
 =
 true
1988                                for
 i
=
1
,
#
o
 do
1989                                    if
 o
[
i
]
 =
=
 tag
 then
1990                                        okay
 =
 false
1991                                        break
1992                                    end
1993                                end
1994                                if
 okay
 then
1995                                    o
[
#
o
+
1
]
 =
 tag
1996                                end
1997                            else
1998                                featureorder
[
lookup
]
 =
 {
 tag
 }
1999                            end
2000                            local
 f
 =
 featurehash
[
lookup
]
2001                            if
 f
 then
2002                                local
 h
 =
 f
[
tag
]
2003                                if
 h
 then
2004                                    local
 s
 =
 h
[
script
]
2005                                    if
 s
 then
2006                                        s
[
language
]
 =
 true
2007                                    else
2008                                        h
[
script
]
 =
 {
 [
language
]
 =
 true
 }
2009                                    end
2010                                else
2011                                    f
[
tag
]
 =
 {
 [
script
]
 =
 {
 [
language
]
 =
 true
 }
 }
2012                                end
2013                            else
2014                                featurehash
[
lookup
]
 =
 {
 [
tag
]
 =
 {
 [
script
]
 =
 {
 [
language
]
 =
 true
 }
 }
 }
2015                            end
2016                            --
2017                            local
 h
 =
 scriptlangs
[
tag
]
2018                            if
 h
 then
2019                                local
 s
 =
 h
[
script
]
2020                                if
 s
 then
2021                                    s
[
language
]
 =
 true
2022                                else
2023                                    h
[
script
]
 =
 {
 [
language
]
 =
 true
 }
2024                                end
2025                            else
2026                                scriptlangs
[
tag
]
 =
 {
 [
script
]
 =
 {
 [
language
]
 =
 true
 }
 }
2027                            end
2028                        end
2029                    end
2030                end
2031            end
2032        end
2033        return
 scriptlangs
,
 featurehash
,
 featureorder
2034    end
2035
2036    local
 function
 readscriplan
(
f
,
fontdata
,
scriptoffset
)
2037        setposition
(
f
,
scriptoffset
)
2038        local
 nofscripts
 =
 readushort
(
f
)
2039        local
 scripts
    =
 {
 }
2040        for
 i
=
1
,
nofscripts
 do
2041            scripts
[
readtag
(
f
)
]
 =
 scriptoffset
 +
 readushort
(
f
)
2042        end
2043        -- script list -> language system info
2044        local
 languagesystems
 =
 setmetatableindex
(
"
table
"
)
2045        for
 script
,
 offset
 in
 next
,
 scripts
 do
2046            setposition
(
f
,
offset
)
2047            local
 defaultoffset
 =
 readushort
(
f
)
2048            local
 noflanguages
  =
 readushort
(
f
)
2049            local
 languages
     =
 {
 }
2050            if
 defaultoffset
 >
 0
 then
2051                languages
.
dflt
 =
 languagesystems
[
offset
 +
 defaultoffset
]
2052            end
2053            for
 i
=
1
,
noflanguages
 do
2054                local
 language
      =
 readtag
(
f
)
2055                local
 offset
        =
 offset
 +
 readushort
(
f
)
2056                languages
[
language
]
 =
 languagesystems
[
offset
]
2057            end
2058            scripts
[
script
]
 =
 languages
2059        end
2060        -- script list -> language system info -> feature list
2061        for
 offset
,
 usedfeatures
 in
 next
,
 languagesystems
 do
2062            if
 offset
 >
 0
 then
2063                setposition
(
f
,
offset
)
2064                local
 featureindices
        =
 {
 }
2065                usedfeatures
.
featureindices
 =
 featureindices
2066                usedfeatures
.
lookuporder
    =
 readushort
(
f
)
 -- reserved, not used (yet)
2067                usedfeatures
.
requiredindex
  =
 readushort
(
f
)
 -- relates to required (can be 0xFFFF)
2068                local
 noffeatures
           =
 readushort
(
f
)
2069                for
 i
=
1
,
noffeatures
 do
2070                    featureindices
[
i
]
 =
 readushort
(
f
)
 +
 1
2071                end
2072            end
2073        end
2074        return
 scripts
2075    end
2076
2077    local
 function
 readfeatures
(
f
,
fontdata
,
featureoffset
)
2078        setposition
(
f
,
featureoffset
)
2079        local
 features
    =
 {
 }
2080        local
 noffeatures
 =
 readushort
(
f
)
2081        for
 i
=
1
,
noffeatures
 do
2082            -- also shared?
2083            features
[
i
]
 =
 {
2084                tag
    =
 readtag
(
f
)
,
2085                offset
 =
 readushort
(
f
)
2086            }
2087        end
2088        --
2089        for
 i
=
1
,
noffeatures
 do
2090            local
 feature
 =
 features
[
i
]
2091            local
 offset
  =
 featureoffset
+
feature
.
offset
2092            setposition
(
f
,
offset
)
2093            local
 parameters
 =
 readushort
(
f
)
 -- feature.parameters
2094            local
 noflookups
 =
 readushort
(
f
)
2095            if
 noflookups
 >
 0
 then
2096--                 local lookups   = { }
2097--                 feature.lookups = lookups
2098--                 for j=1,noflookups do
2099--                     lookups[j] = readushort(f) + 1
2100--                 end
2101                local
 lookups
   =
 readcardinaltable
(
f
,
noflookups
,
ushort
)
2102                feature
.
lookups
 =
 lookups
2103                for
 j
=
1
,
noflookups
 do
2104                    lookups
[
j
]
 =
 lookups
[
j
]
 +
 1
2105                end
2106            end
2107            if
 parameters
 >
 0
 then
2108                feature
.
parameters
 =
 parameters
2109                local
 plugin
 =
 plugins
[
feature
.
tag
]
2110                if
 plugin
 then
2111                    plugin
(
f
,
fontdata
,
featureoffset
,
feature
)
2112                end
2113            end
2114        end
2115        return
 features
2116    end
2117
2118    local
 function
 readlookups
(
f
,
lookupoffset
,
lookuptypes
,
featurehash
,
featureorder
)
2119        setposition
(
f
,
lookupoffset
)
2120        local
 noflookups
 =
 readushort
(
f
)
2121        local
 lookups
    =
 readcardinaltable
(
f
,
noflookups
,
ushort
)
2122        for
 lookupid
=
1
,
noflookups
 do
2123            local
 offset
 =
 lookups
[
lookupid
]
2124            setposition
(
f
,
lookupoffset
+
offset
)
2125            local
 subtables
    =
 {
 }
2126            local
 typebits
     =
 readushort
(
f
)
2127            local
 flagbits
     =
 readushort
(
f
)
2128            local
 lookuptype
   =
 lookuptypes
[
typebits
]
2129            local
 lookupflags
  =
 lookupflags
[
flagbits
]
2130            local
 nofsubtables
 =
 readushort
(
f
)
2131            for
 j
=
1
,
nofsubtables
 do
2132                subtables
[
j
]
 =
 offset
 +
 readushort
(
f
)
 -- we can probably put lookupoffset here
2133            end
2134            -- which one wins?
2135            local
 markclass
 =
 band
(
flagbits
,
0x0010
)
 ~
=
 0
 -- usemarkfilteringset
2136            if
 markclass
 then
2137                markclass
 =
 readushort
(
f
)
 -- + 1
2138            end
2139            local
 markset
 =
 rshift
(
flagbits
,
8
)
2140            if
 markset
 >
 0
 then
2141                markclass
 =
 markset
 -- + 1
2142            end
2143            lookups
[
lookupid
]
 =
 {
2144                type
      =
 lookuptype
,
2145             -- chain     = chaindirections[lookuptype] or nil,
2146                flags
     =
 lookupflags
,
2147                name
      =
 lookupid
,
2148                subtables
 =
 subtables
,
2149                markclass
 =
 markclass
,
2150                features
  =
 featurehash
[
lookupid
]
,
 -- not if extension
2151                order
     =
 featureorder
[
lookupid
]
,
2152            }
2153        end
2154        return
 lookups
2155    end
2156
2157    local
 f_lookupname
 =
 formatters
[
"
%s_%s_%s
"
]
2158
2159    local
 function
 resolvelookups
(
f
,
lookupoffset
,
fontdata
,
lookups
,
lookuptypes
,
lookuphandlers
,
what
,
tableoffset
)
2160
2161        local
 sequences
      =
 fontdata
.
sequences
  or
 {
 }
2162        local
 sublookuplist
  =
 fontdata
.
sublookups
 or
 {
 }
2163        fontdata
.
sequences
   =
 sequences
2164        fontdata
.
sublookups
  =
 sublookuplist
2165        local
 nofsublookups
  =
 #
sublookuplist
2166        local
 nofsequences
   =
 #
sequences
 -- 0
2167        local
 lastsublookup
  =
 nofsublookups
2168        local
 lastsequence
   =
 nofsequences
2169        local
 lookupnames
    =
 lookupnames
[
what
]
2170        local
 sublookuphash
  =
 {
 }
2171        local
 sublookupcheck
 =
 {
 }
2172        local
 glyphs
         =
 fontdata
.
glyphs
2173        local
 nofglyphs
      =
 fontdata
.
nofglyphs
 or
 #
glyphs
2174        local
 noflookups
     =
 #
lookups
2175        local
 lookupprefix
   =
 sub
(
what
,
2
,
2
)
 -- g[s|p][ub|os]
2176        --
2177        local
 usedlookups
    =
 false
 -- setmetatableindex("number")
2178        --
2179        for
 lookupid
=
1
,
noflookups
 do
2180            local
 lookup
     =
 lookups
[
lookupid
]
2181            local
 lookuptype
 =
 lookup
.
type
2182            local
 subtables
  =
 lookup
.
subtables
2183            local
 features
   =
 lookup
.
features
2184            local
 handler
    =
 lookuphandlers
[
lookuptype
]
2185            if
 handler
 then
2186                local
 nofsubtables
 =
 #
subtables
2187                local
 order
        =
 lookup
.
order
2188                local
 flags
        =
 lookup
.
flags
2189                -- this is expected in the font handler (faster checking)
2190                if
 flags
[
1
]
 then
 flags
[
1
]
 =
 "
mark
"
 end
2191                if
 flags
[
2
]
 then
 flags
[
2
]
 =
 "
ligature
"
 end
2192                if
 flags
[
3
]
 then
 flags
[
3
]
 =
 "
base
"
 end
2193                --
2194                local
 markclass
    =
 lookup
.
markclass
2195             -- local chain        = lookup.chain
2196                if
 nofsubtables
 >
 0
 then
2197                    local
 steps
     =
 {
 }
2198                    local
 nofsteps
  =
 0
2199                    local
 oldtype
   =
 nil
2200                    for
 s
=
1
,
nofsubtables
 do
2201                        local
 step
,
 lt
 =
 handler
(
f
,
fontdata
,
lookupid
,
lookupoffset
,
subtables
[
s
]
,
glyphs
,
nofglyphs
)
2202                        if
 lt
 then
2203                            lookuptype
 =
 lt
2204                            if
 oldtype
 and
 lt
 ~
=
 oldtype
 then
2205                                report
(
"
messy %s lookup type %a and %a
"
,
what
,
lookuptype
,
oldtype
)
2206                            end
2207                            oldtype
 =
 lookuptype
2208                        end
2209                        if
 not
 step
 then
2210                            report
(
"
unsupported %s lookup type %a
"
,
what
,
lookuptype
)
2211                        else
2212                            nofsteps
 =
 nofsteps
 +
 1
2213                            steps
[
nofsteps
]
 =
 step
2214                            local
 rules
 =
 step
.
rules
2215                            if
 rules
 then
2216                                for
 i
=
1
,
#
rules
 do
2217                                    local
 rule
         =
 rules
[
i
]
2218                                    local
 before
       =
 rule
.
before
2219                                    local
 current
      =
 rule
.
current
2220                                    local
 after
        =
 rule
.
after
2221                                    local
 replacements
 =
 rule
.
replacements
2222                                    if
 before
 then
2223                                        for
 i
=
1
,
#
before
 do
2224                                            before
[
i
]
 =
 tohash
(
before
[
i
]
)
2225                                        end
2226                                        -- as with original ctx ff loader
2227                                        rule
.
before
 =
 reversed
(
before
)
2228                                    end
2229                                    if
 current
 then
2230                                        if
 replacements
 then
2231                                            -- We have a reverse lookup and therefore only one current entry. We might need
2232                                            -- to reverse the order in the before and after lists so that needs checking.
2233                                            local
 first
 =
 current
[
1
]
2234                                            local
 hash
  =
 {
 }
2235                                            local
 repl
  =
 {
 }
2236                                            for
 i
=
1
,
#
first
 do
2237                                                local
 c
 =
 first
[
i
]
2238                                                hash
[
c
]
 =
 true
2239                                                repl
[
c
]
 =
 replacements
[
i
]
2240                                            end
2241                                            rule
.
current
      =
 {
 hash
 }
2242                                            rule
.
replacements
 =
 repl
2243                                        else
2244                                            for
 i
=
1
,
#
current
 do
2245                                                current
[
i
]
 =
 tohash
(
current
[
i
]
)
2246                                            end
2247                                        end
2248                                    else
2249                                        -- weird lookup
2250                                    end
2251                                    if
 after
 then
2252                                        for
 i
=
1
,
#
after
 do
2253                                            after
[
i
]
 =
 tohash
(
after
[
i
]
)
2254                                        end
2255                                    end
2256                                    if
 usedlookups
 then
2257                                        local
 lookups
 =
 rule
.
lookups
2258                                        if
 lookups
 then
2259                                            for
 k
,
 v
 in
 next
,
 lookups
 do
2260                                                if
 v
 then
2261                                                    for
 k
,
 v
 in
 next
,
 v
 do
2262                                                        usedlookups
[
v
]
 =
 usedlookups
[
v
]
 +
 1
2263                                                    end
2264                                                end
2265                                            end
2266                                        end
2267                                    end
2268                                end
2269                            end
2270                        end
2271                    end
2272                    if
 nofsteps
 ~
=
 nofsubtables
 then
2273                        report
(
"
bogus subtables removed in %s lookup type %a
"
,
what
,
lookuptype
)
2274                    end
2275                    lookuptype
 =
 lookupnames
[
lookuptype
]
 or
 lookuptype
2276                    if
 features
 then
2277                        nofsequences
 =
 nofsequences
 +
 1
2278                     -- report("registering %i as sequence step %i",lookupid,nofsequences)
2279                        local
 l
 =
 {
2280                            index
     =
 nofsequences
,
2281                            name
      =
 f_lookupname
(
lookupprefix
,
"
s
"
,
lookupid
+
lookupidoffset
)
,
2282                            steps
     =
 steps
,
2283                            nofsteps
  =
 nofsteps
,
2284                            type
      =
 lookuptype
,
2285                            markclass
 =
 markclass
 or
 nil
,
2286                            flags
     =
 flags
,
2287                         -- chain     = chain,
2288                            order
     =
 order
,
2289                            features
  =
 features
,
2290                        }
2291                        sequences
[
nofsequences
]
 =
 l
2292                        lookup
.
done
 =
 l
2293                    else
2294                        nofsublookups
 =
 nofsublookups
 +
 1
2295                     -- report("registering %i as sublookup %i",lookupid,nofsublookups)
2296                        local
 l
 =
 {
2297                            index
     =
 nofsublookups
,
2298                            name
      =
 f_lookupname
(
lookupprefix
,
"
l
"
,
lookupid
+
lookupidoffset
)
,
2299                            steps
     =
 steps
,
2300                            nofsteps
  =
 nofsteps
,
2301                            type
      =
 lookuptype
,
2302                            markclass
 =
 markclass
 or
 nil
,
2303                            flags
     =
 flags
,
2304                         -- chain     = chain,
2305                        }
2306                        sublookuplist
[
nofsublookups
]
 =
 l
2307                        sublookuphash
[
lookupid
]
 =
 nofsublookups
2308                        sublookupcheck
[
lookupid
]
 =
 0
2309                        lookup
.
done
 =
 l
2310                    end
2311                else
2312                    report
(
"
no subtables for lookup %a
"
,
lookupid
)
2313                end
2314            else
2315                report
(
"
no handler for lookup %a with type %a
"
,
lookupid
,
lookuptype
)
2316            end
2317        end
2318
2319        if
 usedlookups
 then
2320            report
(
"
used %s lookups: % t
"
,
what
,
sortedkeys
(
usedlookups
)
)
2321        end
2322
2323        -- When we have a context, we have sublookups that resolve into lookups for which we need to
2324        -- know the type. We split the main lookuptable in two parts: sequences (the main lookups)
2325        -- and subtable lookups (simple specs with no features). We could keep them merged and might do
2326        -- that once we only use this loader. Then we can also move the simple specs into the sequence.
2327        -- After all, we pack afterwards.
2328
2329        local
 reported
 =
 {
 }
2330
2331        local
 function
 report_issue
(
i
,
what
,
sequence
,
kind
)
2332            local
 name
 =
 sequence
.
name
2333            if
 not
 reported
[
name
]
 then
2334                report
(
"
rule %i in %s lookup %a has %s lookups
"
,
i
,
what
,
name
,
kind
)
2335                reported
[
name
]
 =
 true
2336            end
2337        end
2338
2339        for
 i
=
lastsequence
+
1
,
nofsequences
 do
2340            local
 sequence
 =
 sequences
[
i
]
2341            local
 steps
    =
 sequence
.
steps
2342            for
 i
=
1
,
#
steps
 do
2343                local
 step
  =
 steps
[
i
]
2344                local
 rules
 =
 step
.
rules
2345                if
 rules
 then
2346                    for
 i
=
1
,
#
rules
 do
2347                        local
 rule
     =
 rules
[
i
]
2348                        local
 rlookups
 =
 rule
.
lookups
2349                        if
 not
 rlookups
 then
2350                            report_issue
(
i
,
what
,
sequence
,
"
no
"
)
2351                        elseif
 not
 next
(
rlookups
)
 then
2352                            -- can be ok as it aborts a chain sequence
2353                         -- report_issue(i,what,sequence,"empty")
2354                            rule
.
lookups
 =
 nil
2355                        else
2356                            -- we can have holes in rlookups flagged false and we can have multiple lookups
2357                            -- applied (first time seen in seguemj)
2358                            local
 length
 =
 #
rlookups
2359                            for
 index
=
1
,
length
 do
2360                                local
 lookuplist
 =
 rlookups
[
index
]
2361                                if
 lookuplist
 then
2362                                    local
 length
   =
 #
lookuplist
2363                                    local
 found
    =
 {
 }
2364                                    local
 noffound
 =
 0
2365                                    for
 index
=
1
,
length
 do
2366                                        local
 lookupid
 =
 lookuplist
[
index
]
2367                                        if
 lookupid
 then
2368                                            local
 h
 =
 sublookuphash
[
lookupid
]
2369                                            if
 not
 h
 then
2370                                                -- here we have a lookup that is used independent as well
2371                                                -- as in another one
2372                                                local
 lookup
 =
 lookups
[
lookupid
]
2373                                                if
 lookup
 then
2374                                                    local
 d
 =
 lookup
.
done
2375                                                    if
 d
 then
2376                                                        nofsublookups
 =
 nofsublookups
 +
 1
2377                                                     -- report("registering %i as sublookup %i",lookupid,nofsublookups)
2378                                                        local
 l
 =
 {
2379                                                            index
     =
 nofsublookups
,
 -- handy for tracing
2380                                                            name
      =
 f_lookupname
(
lookupprefix
,
"
d
"
,
lookupid
+
lookupidoffset
)
,
2381                                                            derived
   =
 true
,
          -- handy for tracing
2382                                                            steps
     =
 d
.
steps
,
2383                                                            nofsteps
  =
 d
.
nofsteps
,
2384                                                            type
      =
 d
.
lookuptype
 or
 "
gsub_single
"
,
 -- todo: check type
2385                                                            markclass
 =
 d
.
markclass
 or
 nil
,
2386                                                            flags
     =
 d
.
flags
,
2387                                                         -- chain     = d.chain,
2388                                                        }
2389                                                        sublookuplist
[
nofsublookups
]
 =
 copy
(
l
)
 -- we repack later
2390                                                        sublookuphash
[
lookupid
]
 =
 nofsublookups
2391                                                        sublookupcheck
[
lookupid
]
 =
 1
2392                                                        h
 =
 nofsublookups
2393                                                    else
2394                                                        report_issue
(
i
,
what
,
sequence
,
"
missing
"
)
2395                                                        rule
.
lookups
 =
 nil
2396                                                        break
2397                                                    end
2398                                                else
2399                                                    report_issue
(
i
,
what
,
sequence
,
"
bad
"
)
2400                                                    rule
.
lookups
 =
 nil
2401                                                    break
2402                                                end
2403                                            else
2404                                                sublookupcheck
[
lookupid
]
 =
 sublookupcheck
[
lookupid
]
 +
 1
2405                                            end
2406                                            if
 h
 then
2407                                                noffound
 =
 noffound
 +
 1
2408                                                found
[
noffound
]
 =
 h
2409                                            end
2410                                        end
2411                                    end
2412                                    rlookups
[
index
]
 =
 noffound
 >
 0
 and
 found
 or
 false
2413                                else
2414                                    rlookups
[
index
]
 =
 false
2415                                end
2416                            end
2417                        end
2418                    end
2419                end
2420            end
2421        end
2422
2423        for
 i
,
 n
 in
 sortedhash
(
sublookupcheck
)
 do
2424            local
 l
 =
 lookups
[
i
]
2425            local
 t
 =
 l
.
type
2426            if
 n
 =
=
 0
 and
 t
 ~
=
 "
extension
"
 then
2427                local
 d
 =
 l
.
done
2428                report
(
"
%s lookup %s of type %a is not used
"
,
what
,
d
 and
 d
.
name
 or
 l
.
name
,
t
)
2429            end
2430        end
2431
2432    end
2433
2434    local
 function
 loadvariations
(
f
,
fontdata
,
variationsoffset
,
lookuptypes
,
featurehash
,
featureorder
)
2435        setposition
(
f
,
variationsoffset
)
2436        local
 version
    =
 readulong
(
f
)
 -- two times readushort
2437        local
 nofrecords
 =
 readulong
(
f
)
2438        local
 records
    =
 {
 }
2439        for
 i
=
1
,
nofrecords
 do
2440            records
[
i
]
 =
 {
2441                conditions
    =
 readulong
(
f
)
,
2442                substitutions
 =
 readulong
(
f
)
,
2443            }
2444        end
2445        for
 i
=
1
,
nofrecords
 do
2446            local
 record
 =
 records
[
i
]
2447            local
 offset
 =
 record
.
conditions
2448            if
 offset
 =
=
 0
 then
2449                record
.
condition
 =
 nil
2450                record
.
matchtype
 =
 "
always
"
2451            else
2452                local
 offset
 =
 variationsoffset
+
offset
2453                setposition
(
f
,
offset
)
2454                local
 nofconditions
 =
 readushort
(
f
)
2455                local
 conditions
    =
 {
 }
2456                for
 i
=
1
,
nofconditions
 do
2457                    conditions
[
i
]
 =
 offset
 +
 readulong
(
f
)
2458                end
2459                record
.
conditions
 =
 conditions
2460                record
.
matchtype
  =
 "
condition
"
2461            end
2462        end
2463        for
 i
=
1
,
nofrecords
 do
2464            local
 record
 =
 records
[
i
]
2465            if
 record
.
matchtype
 =
=
 "
condition
"
 then
2466                local
 conditions
 =
 record
.
conditions
2467                for
 i
=
1
,
#
conditions
 do
2468                    setposition
(
f
,
conditions
[
i
]
)
2469                    conditions
[
i
]
 =
 {
2470                        format
   =
 readushort
(
f
)
,
2471                        axis
     =
 readushort
(
f
)
,
2472                        minvalue
 =
 read2dot14
(
f
)
,
2473                        maxvalue
 =
 read2dot14
(
f
)
,
2474                    }
2475                end
2476            end
2477        end
2478
2479        for
 i
=
1
,
nofrecords
 do
2480            local
 record
 =
 records
[
i
]
2481            local
 offset
 =
 record
.
substitutions
2482            if
 offset
 =
=
 0
 then
2483                record
.
substitutions
 =
 {
 }
2484            else
2485                setposition
(
f
,
variationsoffset
 +
 offset
)
2486                local
 version
          =
 readulong
(
f
)
2487                local
 nofsubstitutions
 =
 readushort
(
f
)
2488                local
 substitutions
    =
 {
 }
2489                for
 i
=
1
,
nofsubstitutions
 do
2490                    substitutions
[
readushort
(
f
)
]
 =
 readulong
(
f
)
2491                end
2492                for
 index
,
 alternates
 in
 sortedhash
(
substitutions
)
 do
2493                    if
 index
 =
=
 0
 then
2494                        record
.
substitutions
 =
 false
2495                    else
2496                        local
 tableoffset
 =
 variationsoffset
 +
 offset
 +
 alternates
2497                        setposition
(
f
,
tableoffset
)
2498                        local
 parameters
 =
 readulong
(
f
)
 -- feature parameters
2499                        local
 noflookups
 =
 readushort
(
f
)
2500                        local
 lookups
    =
 readcardinaltable
(
f
,
noflookups
,
ushort
)
 -- not sure what to do with these
2501                        -- todo : resolve to proper lookups
2502                        record
.
substitutions
 =
 lookups
2503                    end
2504                end
2505            end
2506        end
2507        setvariabledata
(
fontdata
,
"
features
"
,
records
)
2508    end
2509
2510    local
 function
 readscripts
(
f
,
fontdata
,
what
,
lookuptypes
,
lookuphandlers
,
lookupstoo
)
2511        local
 tableoffset
 =
 gotodatatable
(
f
,
fontdata
,
what
,
true
)
2512        if
 tableoffset
 then
2513            local
 version
          =
 readulong
(
f
)
2514            local
 scriptoffset
     =
 tableoffset
 +
 readushort
(
f
)
2515            local
 featureoffset
    =
 tableoffset
 +
 readushort
(
f
)
2516            local
 lookupoffset
     =
 tableoffset
 +
 readushort
(
f
)
2517            local
 variationsoffset
 =
 version
 >
 0x00010000
 and
 (
tableoffset
 +
 readulong
(
f
)
)
 or
 0
2518            if
 not
 scriptoffset
 then
2519                return
2520            end
2521            local
 scripts
  =
 readscriplan
(
f
,
fontdata
,
scriptoffset
)
2522            local
 features
 =
 readfeatures
(
f
,
fontdata
,
featureoffset
)
2523            --
2524            local
 scriptlangs
,
 featurehash
,
 featureorder
 =
 reorderfeatures
(
fontdata
,
scripts
,
features
)
2525            --
2526            if
 fontdata
.
features
 then
2527                fontdata
.
features
[
what
]
 =
 scriptlangs
2528            else
2529                fontdata
.
features
 =
 {
 [
what
]
 =
 scriptlangs
 }
2530            end
2531            --
2532            if
 not
 lookupstoo
 then
2533                return
2534            end
2535            --
2536            local
 lookups
 =
 readlookups
(
f
,
lookupoffset
,
lookuptypes
,
featurehash
,
featureorder
)
2537            --
2538            if
 lookups
 then
2539                resolvelookups
(
f
,
lookupoffset
,
fontdata
,
lookups
,
lookuptypes
,
lookuphandlers
,
what
,
tableoffset
)
2540            end
2541            --
2542            if
 variationsoffset
 >
 0
 then
2543                loadvariations
(
f
,
fontdata
,
variationsoffset
,
lookuptypes
,
featurehash
,
featureorder
)
2544            end
2545        end
2546    end
2547
2548    local
 function
 checkkerns
(
f
,
fontdata
,
specification
)
2549        local
 datatable
 =
 fontdata
.
tables
.
kern
2550        if
 not
 datatable
 then
2551            return
 -- no kerns
2552        end
2553        local
 features
     =
 fontdata
.
features
2554        local
 gposfeatures
 =
 features
 and
 features
.
gpos
2555        local
 name
2556        if
 not
 gposfeatures
 or
 not
 gposfeatures
.
kern
 then
2557            name
 =
 "
kern
"
2558        elseif
 specification
.
globalkerns
 then
2559            name
 =
 "
globalkern
"
2560        else
2561            report
(
"
ignoring global kern table, using gpos kern feature
"
)
2562            return
2563        end
2564        setposition
(
f
,
datatable
.
offset
)
2565        local
 version
   =
 readushort
(
f
)
2566        local
 noftables
 =
 readushort
(
f
)
2567        if
 noftables
 >
 1
 then
2568            report
(
"
adding global kern table as gpos feature %a
"
,
name
)
2569            local
 kerns
 =
 setmetatableindex
(
"
table
"
)
2570            for
 i
=
1
,
noftables
 do
2571                local
 version
  =
 readushort
(
f
)
2572                local
 length
   =
 readushort
(
f
)
2573                local
 coverage
 =
 readushort
(
f
)
2574                -- bit 8-15 of coverage: format 0 or 2
2575                local
 format
   =
 rshift
(
coverage
,
8
)
 -- is this ok
2576                if
 format
 =
=
 0
 then
2577                    local
 nofpairs
      =
 readushort
(
f
)
2578                    local
 searchrange
   =
 readushort
(
f
)
2579                    local
 entryselector
 =
 readushort
(
f
)
2580                    local
 rangeshift
    =
 readushort
(
f
)
2581                    for
 i
=
1
,
nofpairs
 do
2582                        kerns
[
readushort
(
f
)
]
[
readushort
(
f
)
]
 =
 readfword
(
f
)
2583                    end
2584                elseif
 format
 =
=
 2
 then
2585                    -- apple specific so let's ignore it
2586                else
2587                    -- not supported by ms
2588                end
2589            end
2590            local
 feature
 =
 {
 dflt
 =
 {
 dflt
 =
 true
 }
 }
2591            if
 not
 features
 then
2592                fontdata
.
features
 =
 {
 gpos
 =
 {
 [
name
]
 =
 feature
 }
 }
2593            elseif
 not
 gposfeatures
 then
2594                fontdata
.
features
.
gpos
 =
 {
 [
name
]
 =
 feature
 }
2595            else
2596                gposfeatures
[
name
]
 =
 feature
2597            end
2598            local
 sequences
 =
 fontdata
.
sequences
2599            if
 not
 sequences
 then
2600                sequences
 =
 {
 }
2601                fontdata
.
sequences
 =
 sequences
2602            end
2603            local
 nofsequences
 =
 #
sequences
 +
 1
2604            sequences
[
nofsequences
]
 =
 {
2605                index
     =
 nofsequences
,
2606                name
      =
 name
,
2607                steps
     =
 {
2608                    {
2609                        coverage
 =
 kerns
,
2610                        format
   =
 "
kern
"
,
2611                    }
,
2612                }
,
2613                nofsteps
  =
 1
,
2614                type
      =
 "
gpos_pair
"
,
2615                flags
     =
 {
 false
,
 false
,
 false
,
 false
 }
,
2616                order
     =
 {
 name
 }
,
2617                features
  =
 {
 [
name
]
 =
 feature
 }
,
2618            }
2619        else
2620            report
(
"
ignoring empty kern table of feature %a
"
,
name
)
2621        end
2622    end
2623
2624    function
 readers
.
gsub
(
f
,
fontdata
,
specification
)
2625        if
 specification
.
details
 then
2626            readscripts
(
f
,
fontdata
,
"
gsub
"
,
gsubtypes
,
gsubhandlers
,
specification
.
lookups
)
2627        end
2628    end
2629
2630    function
 readers
.
gpos
(
f
,
fontdata
,
specification
)
2631        if
 specification
.
details
 then
2632            readscripts
(
f
,
fontdata
,
"
gpos
"
,
gpostypes
,
gposhandlers
,
specification
.
lookups
)
2633            if
 specification
.
lookups
 then
2634                checkkerns
(
f
,
fontdata
,
specification
)
2635            end
2636        end
2637    end
2638
2639end
2640
2641function
 readers
.
gdef
(
f
,
fontdata
,
specification
)
2642    if
 not
 specification
.
glyphs
 then
2643        return
2644    end
2645    local
 datatable
 =
 fontdata
.
tables
.
gdef
2646    if
 datatable
 then
2647        local
 tableoffset
 =
 datatable
.
offset
2648        setposition
(
f
,
tableoffset
)
2649        local
 version
          =
 readulong
(
f
)
2650        local
 classoffset
      =
 readushort
(
f
)
2651        local
 attachmentoffset
 =
 readushort
(
f
)
 -- used for bitmaps
2652        local
 ligaturecarets
   =
 readushort
(
f
)
 -- used in editors (maybe nice for tracing)
2653        local
 markclassoffset
  =
 readushort
(
f
)
2654        local
 marksetsoffset
   =
 version
 >
=
 0x00010002
 and
 readushort
(
f
)
 or
 0
2655        local
 varsetsoffset
    =
 version
 >
=
 0x00010003
 and
 readulong
(
f
)
 or
 0
2656        local
 glyphs
           =
 fontdata
.
glyphs
2657        local
 marks
            =
 {
 }
2658        local
 markclasses
      =
 setmetatableindex
(
"
table
"
)
2659        local
 marksets
         =
 setmetatableindex
(
"
table
"
)
2660        fontdata
.
marks
         =
 marks
2661        fontdata
.
markclasses
   =
 markclasses
2662        fontdata
.
marksets
      =
 marksets
2663        -- class definitions
2664        if
 classoffset
 ~
=
 0
 then
2665            setposition
(
f
,
tableoffset
 +
 classoffset
)
2666            local
 classformat
 =
 readushort
(
f
)
2667            if
 classformat
 =
=
 1
 then
2668                local
 firstindex
 =
 readushort
(
f
)
2669                local
 lastindex
  =
 firstindex
 +
 readushort
(
f
)
 -
 1
2670                for
 index
=
firstindex
,
lastindex
 do
2671                    local
 class
 =
 classes
[
readushort
(
f
)
]
2672                    if
 class
 =
=
 "
mark
"
 then
2673                        marks
[
index
]
 =
 true
2674                    end
2675                    glyphs
[
index
]
.
class
 =
 class
2676                end
2677            elseif
 classformat
 =
=
 2
 then
2678                local
 nofranges
 =
 readushort
(
f
)
2679                for
 i
=
1
,
nofranges
 do
2680                    local
 firstindex
 =
 readushort
(
f
)
2681                    local
 lastindex
  =
 readushort
(
f
)
2682                    local
 class
      =
 classes
[
readushort
(
f
)
]
2683                    if
 class
 then
2684                        for
 index
=
firstindex
,
lastindex
 do
2685                            glyphs
[
index
]
.
class
 =
 class
2686                            if
 class
 =
=
 "
mark
"
 then
2687                                marks
[
index
]
 =
 true
2688                            end
2689                        end
2690                    end
2691                end
2692            end
2693        end
2694        -- mark classes
2695        if
 markclassoffset
 ~
=
 0
 then
2696            setposition
(
f
,
tableoffset
 +
 markclassoffset
)
2697            local
 classformat
 =
 readushort
(
f
)
2698            if
 classformat
 =
=
 1
 then
2699                local
 firstindex
 =
 readushort
(
f
)
2700                local
 lastindex
  =
 firstindex
 +
 readushort
(
f
)
 -
 1
2701                for
 index
=
firstindex
,
lastindex
 do
2702                    markclasses
[
readushort
(
f
)
]
[
index
]
 =
 true
2703                end
2704            elseif
 classformat
 =
=
 2
 then
2705                local
 nofranges
 =
 readushort
(
f
)
2706                for
 i
=
1
,
nofranges
 do
2707                    local
 firstindex
 =
 readushort
(
f
)
2708                    local
 lastindex
  =
 readushort
(
f
)
2709                    local
 class
      =
 markclasses
[
readushort
(
f
)
]
2710                    for
 index
=
firstindex
,
lastindex
 do
2711                        class
[
index
]
 =
 true
2712                    end
2713                end
2714            end
2715        end
2716        -- mark sets : todo: just make the same as class sets above
2717        if
 marksetsoffset
 ~
=
 0
 then
2718            marksetsoffset
 =
 tableoffset
 +
 marksetsoffset
2719            setposition
(
f
,
marksetsoffset
)
2720            local
 format
 =
 readushort
(
f
)
2721            if
 format
 =
=
 1
 then
2722                local
 nofsets
 =
 readushort
(
f
)
2723                local
 sets
    =
 readcardinaltable
(
f
,
nofsets
,
ulong
)
2724                for
 i
=
1
,
nofsets
 do
2725                    local
 offset
 =
 sets
[
i
]
2726                    if
 offset
 ~
=
 0
 then
2727                        marksets
[
i
]
 =
 readcoverage
(
f
,
marksetsoffset
+
offset
)
2728                    end
2729                end
2730            end
2731        end
2732
2733        local
 factors
 =
 specification
.
factors
2734
2735        if
 (
specification
.
variable
 or
 factors
)
 and
 varsetsoffset
 ~
=
 0
 then
2736
2737            local
 regions
,
 deltas
 =
 readvariationdata
(
f
,
tableoffset
+
varsetsoffset
,
factors
)
2738
2739         -- setvariabledata(fontdata,"gregions",regions)
2740
2741            if
 factors
 then
2742                fontdata
.
temporary
.
getdelta
 =
 function
(
outer
,
inner
)
2743                    local
 delta
 =
 deltas
[
outer
+
1
]
2744                    if
 delta
 then
2745                        local
 d
 =
 delta
.
deltas
[
inner
+
1
]
2746                        if
 d
 then
2747                            local
 scales
 =
 delta
.
scales
2748                            local
 dd
 =
 0
2749                            for
 i
=
1
,
#
scales
 do
2750                                local
 di
 =
 d
[
i
]
2751                                if
 di
 then
2752                                    dd
 =
 dd
 +
 scales
[
i
]
 *
 di
2753                                else
2754                                    break
2755                                end
2756                            end
2757                            return
 round
(
dd
)
2758                        end
2759                    end
2760                    return
 0
2761                end
2762            end
2763
2764        end
2765    end
2766end
2767
2768-- We keep this code here instead of font-otm.lua because we need coverage
2769-- helpers. Okay, these helpers could go to the main reader file some day.
2770
2771local
 function
 readmathvalue
(
f
)
2772    local
 v
 =
 readshort
(
f
)
2773    skipshort
(
f
,
1
)
 -- offset to device table
2774    return
 v
2775end
2776
2777local
 function
 readmathconstants
(
f
,
fontdata
,
offset
)
2778    setposition
(
f
,
offset
)
2779    fontdata
.
mathconstants
 =
 {
2780        ScriptPercentScaleDown
                   =
 readshort
(
f
)
,
2781        ScriptScriptPercentScaleDown
             =
 readshort
(
f
)
,
2782        DelimitedSubFormulaMinHeight
             =
 readushort
(
f
)
,
2783        DisplayOperatorMinHeight
                 =
 readushort
(
f
)
,
2784        MathLeading
                              =
 readmathvalue
(
f
)
,
2785        AxisHeight
                               =
 readmathvalue
(
f
)
,
2786        AccentBaseHeight
                         =
 readmathvalue
(
f
)
,
2787        FlattenedAccentBaseHeight
                =
 readmathvalue
(
f
)
,
2788        SubscriptShiftDown
                       =
 readmathvalue
(
f
)
,
2789        SubscriptTopMax
                          =
 readmathvalue
(
f
)
,
2790        SubscriptBaselineDropMin
                 =
 readmathvalue
(
f
)
,
2791        SuperscriptShiftUp
                       =
 readmathvalue
(
f
)
,
2792        SuperscriptShiftUpCramped
                =
 readmathvalue
(
f
)
,
2793        SuperscriptBottomMin
                     =
 readmathvalue
(
f
)
,
2794        SuperscriptBaselineDropMax
               =
 readmathvalue
(
f
)
,
2795        SubSuperscriptGapMin
                     =
 readmathvalue
(
f
)
,
2796        SuperscriptBottomMaxWithSubscript
        =
 readmathvalue
(
f
)
,
2797        SpaceAfterScript
                         =
 readmathvalue
(
f
)
,
2798        UpperLimitGapMin
                         =
 readmathvalue
(
f
)
,
2799        UpperLimitBaselineRiseMin
                =
 readmathvalue
(
f
)
,
2800        LowerLimitGapMin
                         =
 readmathvalue
(
f
)
,
2801        LowerLimitBaselineDropMin
                =
 readmathvalue
(
f
)
,
2802        StackTopShiftUp
                          =
 readmathvalue
(
f
)
,
2803        StackTopDisplayStyleShiftUp
              =
 readmathvalue
(
f
)
,
2804        StackBottomShiftDown
                     =
 readmathvalue
(
f
)
,
2805        StackBottomDisplayStyleShiftDown
         =
 readmathvalue
(
f
)
,
2806        StackGapMin
                              =
 readmathvalue
(
f
)
,
2807        StackDisplayStyleGapMin
                  =
 readmathvalue
(
f
)
,
2808        StretchStackTopShiftUp
                   =
 readmathvalue
(
f
)
,
2809        StretchStackBottomShiftDown
              =
 readmathvalue
(
f
)
,
2810        StretchStackGapAboveMin
                  =
 readmathvalue
(
f
)
,
2811        StretchStackGapBelowMin
                  =
 readmathvalue
(
f
)
,
2812        FractionNumeratorShiftUp
                 =
 readmathvalue
(
f
)
,
2813        FractionNumeratorDisplayStyleShiftUp
     =
 readmathvalue
(
f
)
,
2814        FractionDenominatorShiftDown
             =
 readmathvalue
(
f
)
,
2815        FractionDenominatorDisplayStyleShiftDown
 =
 readmathvalue
(
f
)
,
2816        FractionNumeratorGapMin
                  =
 readmathvalue
(
f
)
,
2817        FractionNumeratorDisplayStyleGapMin
      =
 readmathvalue
(
f
)
,
2818        FractionRuleThickness
                    =
 readmathvalue
(
f
)
,
2819        FractionDenominatorGapMin
                =
 readmathvalue
(
f
)
,
2820        FractionDenominatorDisplayStyleGapMin
    =
 readmathvalue
(
f
)
,
2821        SkewedFractionHorizontalGap
              =
 readmathvalue
(
f
)
,
2822        SkewedFractionVerticalGap
                =
 readmathvalue
(
f
)
,
2823        OverbarVerticalGap
                       =
 readmathvalue
(
f
)
,
2824        OverbarRuleThickness
                     =
 readmathvalue
(
f
)
,
2825        OverbarExtraAscender
                     =
 readmathvalue
(
f
)
,
2826        UnderbarVerticalGap
                      =
 readmathvalue
(
f
)
,
2827        UnderbarRuleThickness
                    =
 readmathvalue
(
f
)
,
2828        UnderbarExtraDescender
                   =
 readmathvalue
(
f
)
,
2829        RadicalVerticalGap
                       =
 readmathvalue
(
f
)
,
2830        RadicalDisplayStyleVerticalGap
           =
 readmathvalue
(
f
)
,
2831        RadicalRuleThickness
                     =
 readmathvalue
(
f
)
,
2832        RadicalExtraAscender
                     =
 readmathvalue
(
f
)
,
2833        RadicalKernBeforeDegree
                  =
 readmathvalue
(
f
)
,
2834        RadicalKernAfterDegree
                   =
 readmathvalue
(
f
)
,
2835        RadicalDegreeBottomRaisePercent
          =
 readshort
(
f
)
,
2836    }
2837end
2838
2839local
 function
 readmathglyphinfo
(
f
,
fontdata
,
offset
)
2840    setposition
(
f
,
offset
)
2841    local
 italics
    =
 readushort
(
f
)
2842    local
 accents
    =
 readushort
(
f
)
2843    local
 extensions
 =
 readushort
(
f
)
2844    local
 kerns
      =
 readushort
(
f
)
2845    local
 glyphs
     =
 fontdata
.
glyphs
2846    if
 italics
 ~
=
 0
 then
2847        setposition
(
f
,
offset
+
italics
)
2848        local
 coverage
  =
 readushort
(
f
)
2849        local
 nofglyphs
 =
 readushort
(
f
)
2850        coverage
 =
 readcoverage
(
f
,
offset
+
italics
+
coverage
,
true
)
2851        setposition
(
f
,
offset
+
italics
+
4
)
2852        for
 i
=
1
,
nofglyphs
 do
2853            local
 italic
 =
 readmathvalue
(
f
)
2854            if
 italic
 ~
=
 0
 then
2855                local
 glyph
 =
 glyphs
[
coverage
[
i
]
]
2856                local
 math
  =
 glyph
.
math
2857                if
 not
 math
 then
2858                    glyph
.
math
 =
 {
 italic
 =
 italic
 }
2859                else
2860                    math
.
italic
 =
 italic
2861                end
2862            end
2863        end
2864        fontdata
.
hasitalics
 =
 true
2865    end
2866    if
 accents
 ~
=
 0
 then
2867        setposition
(
f
,
offset
+
accents
)
2868        local
 coverage
  =
 readushort
(
f
)
2869        local
 nofglyphs
 =
 readushort
(
f
)
2870        coverage
 =
 readcoverage
(
f
,
offset
+
accents
+
coverage
,
true
)
2871        setposition
(
f
,
offset
+
accents
+
4
)
2872        for
 i
=
1
,
nofglyphs
 do
2873            local
 accent
 =
 readmathvalue
(
f
)
2874            if
 accent
 ~
=
 0
 then
2875                local
 glyph
 =
 glyphs
[
coverage
[
i
]
]
2876                local
 math
  =
 glyph
.
math
2877                if
 not
 math
 then
2878                    glyph
.
math
 =
 {
 accent
 =
 accent
 }
2879                else
2880                    math
.
accent
 =
 accent
2881                end
2882            end
2883        end
2884    end
2885    if
 extensions
 ~
=
 0
 then
2886        setposition
(
f
,
offset
+
extensions
)
2887    end
2888    if
 kerns
 ~
=
 0
 then
2889        local
 kernoffset
 =
 offset
 +
 kerns
2890        setposition
(
f
,
kernoffset
)
2891        local
 coverage
  =
 readushort
(
f
)
2892        local
 nofglyphs
 =
 readushort
(
f
)
2893        if
 nofglyphs
 >
 0
 then
2894            local
 function
 get
(
offset
)
2895                setposition
(
f
,
kernoffset
+
offset
)
2896                local
 n
 =
 readushort
(
f
)
2897                if
 n
 =
=
 0
 then
2898                    local
 k
 =
 readmathvalue
(
f
)
2899                    if
 k
 =
=
 0
 then
2900                        -- no need for it (happens sometimes)
2901                    else
2902                        return
 {
 {
 kern
 =
 k
 }
 }
2903                    end
2904                else
2905                    local
 l
 =
 {
 }
2906                    for
 i
=
1
,
n
 do
2907                        l
[
i
]
 =
 {
 height
 =
 readmathvalue
(
f
)
 }
2908                    end
2909                    for
 i
=
1
,
n
 do
2910                        l
[
i
]
.
kern
 =
 readmathvalue
(
f
)
2911                    end
2912                    l
[
n
+
1
]
 =
 {
 kern
 =
 readmathvalue
(
f
)
 }
2913                    return
 l
2914                end
2915            end
2916            local
 kernsets
 =
 {
 }
2917            for
 i
=
1
,
nofglyphs
 do
2918                local
 topright
    =
 readushort
(
f
)
2919                local
 topleft
     =
 readushort
(
f
)
2920                local
 bottomright
 =
 readushort
(
f
)
2921                local
 bottomleft
  =
 readushort
(
f
)
2922                kernsets
[
i
]
 =
 {
2923                    topright
    =
 topright
    ~
=
 0
 and
 topright
    or
 nil
,
2924                    topleft
     =
 topleft
     ~
=
 0
 and
 topleft
     or
 nil
,
2925                    bottomright
 =
 bottomright
 ~
=
 0
 and
 bottomright
 or
 nil
,
2926                    bottomleft
  =
 bottomleft
  ~
=
 0
 and
 bottomleft
  or
 nil
,
2927                }
2928            end
2929            coverage
 =
 readcoverage
(
f
,
kernoffset
+
coverage
,
true
)
2930            for
 i
=
1
,
nofglyphs
 do
2931                local
 kernset
 =
 kernsets
[
i
]
2932                if
 next
(
kernset
)
 then
2933                    local
 k
 =
 kernset
.
topright
    if
 k
 then
 kernset
.
topright
    =
 get
(
k
)
 end
2934                    local
 k
 =
 kernset
.
topleft
     if
 k
 then
 kernset
.
topleft
     =
 get
(
k
)
 end
2935                    local
 k
 =
 kernset
.
bottomright
 if
 k
 then
 kernset
.
bottomright
 =
 get
(
k
)
 end
2936                    local
 k
 =
 kernset
.
bottomleft
  if
 k
 then
 kernset
.
bottomleft
  =
 get
(
k
)
 end
2937                    if
 next
(
kernset
)
 then
2938                        local
 glyph
 =
 glyphs
[
coverage
[
i
]
]
2939                        local
 math
  =
 glyph
.
math
2940                        if
 math
 then
2941                            math
.
kerns
 =
 kernset
2942                        else
2943                            glyph
.
math
 =
 {
 kerns
 =
 kernset
 }
2944                        end
2945                    end
2946                end
2947            end
2948        end
2949    end
2950end
2951
2952local
 function
 readmathvariants
(
f
,
fontdata
,
offset
)
2953    setposition
(
f
,
offset
)
2954    local
 glyphs
        =
 fontdata
.
glyphs
2955    local
 minoverlap
    =
 readushort
(
f
)
2956    local
 vcoverage
     =
 readushort
(
f
)
2957    local
 hcoverage
     =
 readushort
(
f
)
2958    local
 vnofglyphs
    =
 readushort
(
f
)
2959    local
 hnofglyphs
    =
 readushort
(
f
)
2960    local
 vconstruction
 =
 readcardinaltable
(
f
,
vnofglyphs
,
ushort
)
2961    local
 hconstruction
 =
 readcardinaltable
(
f
,
hnofglyphs
,
ushort
)
2962
2963    fontdata
.
mathconstants
.
MinConnectorOverlap
 =
 minoverlap
2964
2965    -- variants[i] = {
2966    --     glyph   = readushort(f),
2967    --     advance = readushort(f),
2968    -- }
2969
2970    local
 function
 get
(
offset
,
coverage
,
nofglyphs
,
construction
,
kvariants
,
kparts
,
kitalic
)
2971        if
 coverage
 ~
=
 0
 and
 nofglyphs
 >
 0
 then
2972            local
 coverage
 =
 readcoverage
(
f
,
offset
+
coverage
,
true
)
2973            for
 i
=
1
,
nofglyphs
 do
2974                local
 c
 =
 construction
[
i
]
2975                if
 c
 ~
=
 0
 then
2976                    local
 index
 =
 coverage
[
i
]
2977                    local
 glyph
 =
 glyphs
[
index
]
2978                    local
 math
  =
 glyph
.
math
2979                    setposition
(
f
,
offset
+
c
)
2980                    local
 assembly
    =
 readushort
(
f
)
2981                    local
 nofvariants
 =
 readushort
(
f
)
2982                    if
 nofvariants
 >
 0
 then
2983                        local
 variants
,
 v
 =
 nil
,
 0
2984                        for
 i
=
1
,
nofvariants
 do
2985                            local
 variant
 =
 readushort
(
f
)
2986                            if
 variant
 =
=
 index
 then
2987                                -- ignore
2988                            elseif
 variants
 then
2989                                v
 =
 v
 +
 1
2990                                variants
[
v
]
 =
 variant
2991                            else
2992                                v
 =
 1
2993                                variants
 =
 {
 variant
 }
2994                            end
2995                            skipshort
(
f
)
2996                        end
2997                        if
 not
 variants
 then
2998                            -- only self
2999                        elseif
 not
 math
 then
3000                            math
 =
 {
 [
kvariants
]
 =
 variants
 }
3001                            glyph
.
math
 =
 math
3002                        else
3003                            math
[
kvariants
]
 =
 variants
3004                        end
3005                    end
3006                    if
 assembly
 ~
=
 0
 then
3007                        setposition
(
f
,
offset
 +
 c
 +
 assembly
)
3008                        local
 italic
   =
 readmathvalue
(
f
)
3009                        local
 nofparts
 =
 readushort
(
f
)
3010                        local
 parts
    =
 {
 }
3011                        for
 i
=
1
,
nofparts
 do
3012                            local
 p
 =
 {
3013                                glyph
   =
 readushort
(
f
)
,
3014                                start
   =
 readushort
(
f
)
,
3015                                [
"
end
"
]
 =
 readushort
(
f
)
,
3016                                advance
 =
 readushort
(
f
)
,
3017                            }
3018                            local
 flags
 =
 readushort
(
f
)
3019                            if
 band
(
flags
,
0x0001
)
 ~
=
 0
 then
3020                                p
.
extender
 =
 1
 -- true
3021                            end
3022                            parts
[
i
]
 =
 p
3023                        end
3024                        if
 not
 math
 then
3025                            math
 =
 {
3026                                [
kparts
]
 =
 parts
3027                            }
3028                            glyph
.
math
 =
 math
3029                        else
3030                            math
[
kparts
]
 =
 parts
3031                        end
3032                        if
 italic
 and
 italic
 ~
=
 0
 then
3033                            math
[
kitalic
]
 =
 italic
3034                        end
3035                    end
3036                end
3037            end
3038        end
3039    end
3040
3041    get
(
offset
,
vcoverage
,
vnofglyphs
,
vconstruction
,
"
vvariants
"
,
"
vparts
"
,
"
vitalic
"
)
3042    get
(
offset
,
hcoverage
,
hnofglyphs
,
hconstruction
,
"
hvariants
"
,
"
hparts
"
,
"
hitalic
"
)
3043end
3044
3045function
 readers
.
math
(
f
,
fontdata
,
specification
)
3046    local
 tableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
math
"
,
specification
.
glyphs
)
3047    if
 tableoffset
 then
3048        local
 version
 =
 readulong
(
f
)
3049     -- if version ~= 0x00010000 then
3050     --     report("table version %a of %a is not supported (yet), maybe font %s is bad",version,"math",fontdata.filename)
3051     --     return
3052     -- end
3053        local
 constants
 =
 readushort
(
f
)
3054        local
 glyphinfo
 =
 readushort
(
f
)
3055        local
 variants
  =
 readushort
(
f
)
3056        if
 constants
 =
=
 0
 then
3057            report
(
"
the math table of %a has no constants
"
,
fontdata
.
filename
)
3058        else
3059            readmathconstants
(
f
,
fontdata
,
tableoffset
+
constants
)
3060        end
3061        if
 glyphinfo
 ~
=
 0
 then
3062            readmathglyphinfo
(
f
,
fontdata
,
tableoffset
+
glyphinfo
)
3063        end
3064        if
 variants
 ~
=
 0
 then
3065            readmathvariants
(
f
,
fontdata
,
tableoffset
+
variants
)
3066        end
3067    end
3068end
3069
3070function
 readers
.
colr
(
f
,
fontdata
,
specification
)
3071    local
 tableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
colr
"
,
specification
.
glyphs
)
3072    if
 tableoffset
 then
3073        local
 version
 =
 readushort
(
f
)
3074        if
 version
 ~
=
 0
 then
3075            report
(
"
table version %a of %a is not supported (yet), maybe font %s is bad
"
,
version
,
"
colr
"
,
fontdata
.
filename
)
3076            return
3077        end
3078        if
 not
 fontdata
.
tables
.
cpal
 then
3079            report
(
"
color table %a in font %a has no mandate %a table
"
,
"
colr
"
,
fontdata
.
filename
,
"
cpal
"
)
3080            fontdata
.
colorpalettes
 =
 {
 }
3081        end
3082        local
 glyphs
       =
 fontdata
.
glyphs
3083        local
 nofglyphs
    =
 readushort
(
f
)
3084        local
 baseoffset
   =
 readulong
(
f
)
3085        local
 layeroffset
  =
 readulong
(
f
)
3086        local
 noflayers
    =
 readushort
(
f
)
3087        local
 layerrecords
 =
 {
 }
3088        local
 maxclass
     =
 0
3089        -- The special value 0xFFFF is foreground (but we index from 1). It
3090        -- more looks like indices into a palette so 'class' is a better name
3091        -- than 'palette'.
3092        setposition
(
f
,
tableoffset
 +
 layeroffset
)
3093        for
 i
=
1
,
noflayers
 do
3094            local
 slot
  =
 readushort
(
f
)
3095            local
 class
 =
 readushort
(
f
)
3096            if
 class
 <
 0xFFFF
 then
3097                class
 =
 class
 +
 1
3098                if
 class
 >
 maxclass
 then
3099                    maxclass
 =
 class
3100                end
3101            end
3102            layerrecords
[
i
]
 =
 {
3103                slot
  =
 slot
,
3104                class
 =
 class
,
3105            }
3106        end
3107        fontdata
.
maxcolorclass
 =
 maxclass
3108        setposition
(
f
,
tableoffset
 +
 baseoffset
)
3109        for
 i
=
0
,
nofglyphs
-1
 do
3110            local
 glyphindex
 =
 readushort
(
f
)
3111            local
 firstlayer
 =
 readushort
(
f
)
3112            local
 noflayers
  =
 readushort
(
f
)
3113            local
 t
 =
 {
 }
3114            for
 i
=
1
,
noflayers
 do
3115                t
[
i
]
 =
 layerrecords
[
firstlayer
+
i
]
3116            end
3117            glyphs
[
glyphindex
]
.
colors
 =
 t
3118        end
3119    end
3120    fontdata
.
hascolor
 =
 true
3121end
3122
3123function
 readers
.
cpal
(
f
,
fontdata
,
specification
)
3124    local
 tableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
cpal
"
,
specification
.
glyphs
)
3125    if
 tableoffset
 then
3126        local
 version
 =
 readushort
(
f
)
3127     -- if version > 1 then
3128     --     report("table version %a of %a is not supported (yet), maybe font %s is bad",version,"cpal",fontdata.filename)
3129     --     return
3130     -- end
3131        local
 nofpaletteentries
  =
 readushort
(
f
)
3132        local
 nofpalettes
        =
 readushort
(
f
)
3133        local
 nofcolorrecords
    =
 readushort
(
f
)
3134        local
 firstcoloroffset
   =
 readulong
(
f
)
3135        local
 colorrecords
       =
 {
 }
3136        local
 palettes
           =
 readcardinaltable
(
f
,
nofpalettes
,
ushort
)
3137        if
 version
 =
=
 1
 then
3138            -- used for guis
3139            local
 palettettypesoffset
 =
 readulong
(
f
)
3140            local
 palettelabelsoffset
 =
 readulong
(
f
)
3141            local
 paletteentryoffset
  =
 readulong
(
f
)
3142        end
3143        setposition
(
f
,
tableoffset
+
firstcoloroffset
)
3144        for
 i
=
1
,
nofcolorrecords
 do
3145            local
 b
,
 g
,
 r
,
 a
 =
 readbytes
(
f
,
4
)
3146            colorrecords
[
i
]
 =
 {
3147                r
,
 g
,
 b
,
 a
 ~
=
 255
 and
 a
 or
 nil
,
3148            }
3149        end
3150        for
 i
=
1
,
nofpalettes
 do
3151            local
 p
 =
 {
 }
3152            local
 o
 =
 palettes
[
i
]
3153            for
 j
=
1
,
nofpaletteentries
 do
3154                p
[
j
]
 =
 colorrecords
[
o
+
j
]
3155            end
3156            palettes
[
i
]
 =
 p
3157        end
3158        fontdata
.
colorpalettes
 =
 palettes
3159    end
3160end
3161
3162local
 compress
   =
 gzip
 and
 gzip
.
compress
3163local
 compressed
 =
 compress
 and
 gzip
.
compressed
3164
3165-- At some point I will delay loading and only store the offsets (in context lmtx
3166-- only).
3167
3168-- compressed = false
3169
3170function
 readers
.
svg
(
f
,
fontdata
,
specification
)
3171    local
 tableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
svg
"
,
specification
.
glyphs
)
3172    if
 tableoffset
 then
3173        local
 version
 =
 readushort
(
f
)
3174     -- if version ~= 0 then
3175     --     report("table version %a of %a is not supported (yet), maybe font %s is bad",version,"svg",fontdata.filename)
3176     --     return
3177     -- end
3178        local
 glyphs
      =
 fontdata
.
glyphs
3179        local
 indexoffset
 =
 tableoffset
 +
 readulong
(
f
)
3180        local
 reserved
    =
 readulong
(
f
)
3181        setposition
(
f
,
indexoffset
)
3182        local
 nofentries
  =
 readushort
(
f
)
3183        local
 entries
     =
 {
 }
3184        for
 i
=
1
,
nofentries
 do
3185            entries
[
i
]
 =
 {
3186                first
  =
 readushort
(
f
)
,
3187                last
   =
 readushort
(
f
)
,
3188                offset
 =
 indexoffset
 +
 readulong
(
f
)
,
3189                length
 =
 readulong
(
f
)
,
3190            }
3191        end
3192        for
 i
=
1
,
nofentries
 do
3193            local
 entry
 =
 entries
[
i
]
3194            setposition
(
f
,
entry
.
offset
)
3195            local
 data
 =
 readstring
(
f
,
entry
.
length
)
3196            if
 compressed
 and
 not
 compressed
(
data
)
 then
3197                data
 =
 compress
(
data
)
3198            end
3199            entries
[
i
]
 =
 {
3200                first
 =
 entry
.
first
,
3201                last
  =
 entry
.
last
,
3202                data
  =
 data
3203            }
3204        end
3205        fontdata
.
svgshapes
 =
 entries
3206    end
3207    fontdata
.
hascolor
 =
 true
3208end
3209
3210function
 readers
.
sbix
(
f
,
fontdata
,
specification
)
3211    local
 tableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
sbix
"
,
specification
.
glyphs
)
3212    if
 tableoffset
 then
3213        local
 version
    =
 readushort
(
f
)
3214        local
 flags
      =
 readushort
(
f
)
3215        local
 nofstrikes
 =
 readulong
(
f
)
3216        local
 strikes
    =
 {
 }
3217        local
 nofglyphs
  =
 fontdata
.
nofglyphs
3218        for
 i
=
1
,
nofstrikes
 do
3219            strikes
[
i
]
 =
 readulong
(
f
)
3220        end
3221        local
 shapes
 =
 {
 }
3222        local
 done
   =
 0
3223        for
 i
=
1
,
nofstrikes
 do
3224            local
 strikeoffset
 =
 strikes
[
i
]
 +
 tableoffset
3225            setposition
(
f
,
strikeoffset
)
3226            strikes
[
i
]
 =
 {
3227                ppem
   =
 readushort
(
f
)
,
3228                ppi
    =
 readushort
(
f
)
,
3229                offset
 =
 strikeoffset
3230            }
3231        end
3232        -- highest first
3233        sort
(
strikes
,
function
(
a
,
b
)
3234            if
 b
.
ppem
 =
=
 a
.
ppem
 then
3235                return
 b
.
ppi
 <
 a
.
ppi
3236            else
3237                return
 b
.
ppem
 <
 a
.
ppem
3238            end
3239        end
)
3240        local
 glyphs
  =
 {
 }
3241        local
 delayed
 =
 CONTEXTLMTXMODE
 and
 CONTEXTLMTXMODE
 >
 0
 or
 fonts
.
handlers
.
typethree
3242        for
 i
=
1
,
nofstrikes
 do
3243            local
 strike
       =
 strikes
[
i
]
3244            local
 strikeppem
   =
 strike
.
ppem
3245            local
 strikeppi
    =
 strike
.
ppi
3246            local
 strikeoffset
 =
 strike
.
offset
3247            setposition
(
f
,
strikeoffset
)
3248            for
 i
=
0
,
nofglyphs
 do
3249                glyphs
[
i
]
 =
 readulong
(
f
)
3250            end
3251            local
 glyphoffset
 =
 glyphs
[
0
]
3252            for
 i
=
0
,
nofglyphs
-1
 do
3253                local
 nextoffset
 =
 glyphs
[
i
+
1
]
3254                if
 not
 shapes
[
i
]
 then
3255                    local
 datasize
 =
 nextoffset
 -
 glyphoffset
3256                    if
 datasize
 >
 0
 then
3257                        setposition
(
f
,
strikeoffset
 +
 glyphoffset
)
3258                        local
 x
      =
 readshort
(
f
)
3259                        local
 y
      =
 readshort
(
f
)
3260                        local
 tag
    =
 readtag
(
f
)
 -- or just skip, we never needed it till now
3261                        local
 size
   =
 datasize
 -
 8
3262                        local
 data
   =
 nil
3263                        local
 offset
 =
 nil
3264                        if
 delayed
 then
3265                            offset
 =
 getposition
(
f
)
3266                            data
   =
 nil
3267                        else
3268                            data
   =
 readstring
(
f
,
size
)
3269                            size
   =
 nil
3270                        end
3271                        shapes
[
i
]
 =
 {
3272                            x
    =
 x
,
3273                            y
    =
 y
,
3274                            o
    =
 offset
,
3275                            s
    =
 size
,
3276                            data
 =
 data
,
3277                         -- tag  = tag, -- maybe for tracing
3278                         -- ppem = strikeppem, -- not used, for tracing
3279                         -- ppi  = strikeppi,  -- not used, for tracing
3280                        }
3281                        done
 =
 done
 +
 1
3282                        if
 done
 =
=
 nofglyphs
 then
3283                            break
3284                        end
3285                    end
3286                end
3287                glyphoffset
 =
 nextoffset
3288            end
3289        end
3290        fontdata
.
pngshapes
 =
 shapes
3291    end
3292end
3293
3294-- Another bitmap (so not that useful) format. But Luigi found a font that
3295-- has them , so ...
3296
3297do
3298
3299    local
 function
 getmetrics
(
f
)
3300        return
 {
3301            ascender
              =
 readinteger
(
f
)
,
3302            descender
             =
 readinteger
(
f
)
,
3303            widthmax
              =
 readuinteger
(
f
)
,
3304            caretslopedumerator
   =
 readinteger
(
f
)
,
3305            caretslopedenominator
 =
 readinteger
(
f
)
,
3306            caretoffset
           =
 readinteger
(
f
)
,
3307            minorigin
             =
 readinteger
(
f
)
,
3308            minadvance
            =
 readinteger
(
f
)
,
3309            maxbefore
             =
 readinteger
(
f
)
,
3310            minafter
              =
 readinteger
(
f
)
,
3311            pad1
                  =
 readinteger
(
f
)
,
3312            pad2
                  =
 readinteger
(
f
)
,
3313        }
3314    end
3315
3316    -- bad names
3317
3318    local
 function
 getbigmetrics
(
f
)
3319        -- bigmetrics, maybe just skip 9 bytes
3320        return
 {
3321            height
       =
 readuinteger
(
f
)
,
3322            width
        =
 readuinteger
(
f
)
,
3323            horiBearingX
 =
 readinteger
(
f
)
,
3324            horiBearingY
 =
 readinteger
(
f
)
,
3325            horiAdvance
  =
 readuinteger
(
f
)
,
3326            vertBearingX
 =
 readinteger
(
f
)
,
3327            vertBearingY
 =
 readinteger
(
f
)
,
3328            vertAdvance
  =
 readuinteger
(
f
)
,
3329        }
3330    end
3331
3332    local
 function
 getsmallmetrics
(
f
)
3333        -- smallmetrics, maybe just skip 5 bytes
3334        return
 {
3335            height
   =
 readuinteger
(
f
)
,
3336            width
    =
 readuinteger
(
f
)
,
3337            bearingX
 =
 readinteger
(
f
)
,
3338            bearingY
 =
 readinteger
(
f
)
,
3339            advance
  =
 readuinteger
(
f
)
,
3340        }
3341    end
3342
3343    function
 readers
.
cblc
(
f
,
fontdata
,
specification
)
3344        -- should we delay this ?
3345        local
 ctdttableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
cbdt
"
,
specification
.
glyphs
)
3346        if
 not
 ctdttableoffset
 then
3347            return
3348        end
3349        local
 cblctableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
cblc
"
,
specification
.
glyphs
)
3350        if
 cblctableoffset
 then
3351            local
 majorversion
  =
 readushort
(
f
)
3352            local
 minorversion
  =
 readushort
(
f
)
3353            local
 nofsizetables
 =
 readulong
(
f
)
3354            local
 sizetables
    =
 {
 }
3355            local
 shapes
        =
 {
 }
3356            local
 subtables
     =
 {
 }
3357            for
 i
=
1
,
nofsizetables
 do
3358                sizetables
[
i
]
 =
 {
3359                    subtables
    =
 readulong
(
f
)
,
3360                    indexsize
    =
 readulong
(
f
)
,
3361                    nofsubtables
 =
 readulong
(
f
)
,
3362                    colorref
     =
 readulong
(
f
)
,
3363                    hormetrics
   =
 getmetrics
(
f
)
,
3364                    vermetrics
   =
 getmetrics
(
f
)
,
3365                    firstindex
   =
 readushort
(
f
)
,
3366                    lastindex
    =
 readushort
(
f
)
,
3367                    ppemx
        =
 readbyte
(
f
)
,
3368                    ppemy
        =
 readbyte
(
f
)
,
3369                    bitdepth
     =
 readbyte
(
f
)
,
3370                    flags
        =
 readbyte
(
f
)
,
3371                }
3372            end
3373            sort
(
sizetables
,
function
(
a
,
b
)
3374                if
 b
.
ppemx
 =
=
 a
.
ppemx
 then
3375                    return
 b
.
bitdepth
 <
 a
.
bitdepth
3376                else
3377                    return
 b
.
ppemx
 <
 a
.
ppemx
3378                end
3379            end
)
3380            for
 i
=
1
,
nofsizetables
 do
3381                local
 s
 =
 sizetables
[
i
]
3382                local
 d
 =
 false
3383                for
 j
=
s
.
firstindex
,
s
.
lastindex
 do
3384                    if
 not
 shapes
[
j
]
 then
3385                        shapes
[
j
]
 =
 i
3386                        d
 =
 true
3387                    end
3388                end
3389                if
 d
 then
3390                    s
.
used
 =
 true
3391                end
3392            end
3393            for
 i
=
1
,
nofsizetables
 do
3394                local
 s
 =
 sizetables
[
i
]
3395                if
 s
.
used
 then
3396                    local
 offset
 =
 s
.
subtables
3397                    setposition
(
f
,
cblctableoffset
+
offset
)
3398                    for
 j
=
1
,
s
.
nofsubtables
 do
3399                        local
 firstindex
  =
 readushort
(
f
)
3400                        local
 lastindex
   =
 readushort
(
f
)
3401                        local
 tableoffset
 =
 readulong
(
f
)
 +
 offset
3402                        for
 k
=
firstindex
,
lastindex
 do
3403                            if
 shapes
[
k
]
 =
=
 i
 then
3404                                local
 s
 =
 subtables
[
tableoffset
]
3405                                if
 not
 s
 then
3406                                    s
 =
 {
3407                                        firstindex
 =
 firstindex
,
3408                                        lastindex
  =
 lastindex
,
3409                                    }
3410                                    subtables
[
tableoffset
]
 =
 s
3411                                end
3412                                shapes
[
k
]
 =
 s
3413                            end
3414                        end
3415                    end
3416                end
3417            end
3418
3419            -- there is no need to sort in string stream but we have a nicer trace
3420            -- if needed
3421
3422            for
 offset
,
 subtable
 in
 sortedhash
(
subtables
)
 do
3423                local
 tabletype
  =
 readushort
(
f
)
3424                subtable
.
format
  =
 readushort
(
f
)
3425                local
 baseoffset
 =
 readulong
(
f
)
 +
 ctdttableoffset
3426                local
 offsets
    =
 {
 }
3427                local
 metrics
    =
 nil
3428                if
 tabletype
 =
=
 1
 then
3429                    -- we have the usual one more to get the size
3430                    for
 i
=
subtable
.
firstindex
,
subtable
.
lastindex
 do
3431                        offsets
[
i
]
 =
 readulong
(
f
)
 +
 baseoffset
3432                    end
3433                    skipbytes
(
f
,
4
)
3434                elseif
 tabletype
 =
=
 2
 then
3435                    local
 size
 =
 readulong
(
f
)
3436                    local
 done
 =
 baseoffset
3437                    metrics
 =
 getbigmetrics
(
f
)
3438                    for
 i
=
subtable
.
firstindex
,
subtable
.
lastindex
 do
3439                        offsets
[
i
]
 =
 done
3440                        done
 =
 done
 +
 size
3441                    end
3442                elseif
 tabletype
 =
=
 3
 then
3443                    -- we have the usual one more to get the size
3444                    local
 n
 =
 subtable
.
lastindex
 -
 subtable
.
firstindex
 +
 2
3445                    for
 i
=
subtable
.
firstindex
,
subtable
.
lastindex
 do
3446                        offsets
[
i
]
 =
 readushort
(
f
)
 +
 baseoffset
3447                    end
3448                    if
 math
.
odd
(
n
)
 then
3449                        skipbytes
(
f
,
4
)
3450                    else
3451                        skipbytes
(
f
,
2
)
3452                    end
3453                elseif
 tabletype
 =
=
 4
 then
3454                    for
 i
=
1
,
readulong
(
f
)
 do
3455                        offsets
[
readushort
(
f
)
]
 =
 readushort
(
f
)
 +
 baseoffset
3456                    end
3457                elseif
 tabletype
 =
=
 5
 then
3458                    local
 size
 =
 readulong
(
f
)
3459                    local
 done
 =
 baseoffset
3460                    metrics
 =
 getbigmetrics
(
f
)
3461                    local
 n
 =
 readulong
(
f
)
3462                    for
 i
=
1
,
n
 do
3463                        offsets
[
readushort
(
f
)
]
 =
 done
3464                        done
 =
 done
 +
 size
3465                    end
3466                    if
 math
.
odd
(
n
)
 then
3467                        skipbytes
(
f
,
2
)
3468                    end
3469                else
3470                    return
 -- unsupported format
3471                end
3472                subtable
.
offsets
 =
 offsets
3473                subtable
.
metrics
 =
 metrics
3474            end
3475
3476            -- we only support a few sensible types ... there are hardly any fonts so
3477            -- why are there so many variants ... not the best spec
3478
3479            local
 default
 =
 {
 width
 =
 0
,
 height
 =
 0
 }
3480            local
 glyphs
  =
 fontdata
.
glyphs
3481            local
 delayed
 =
 CONTEXTLMTXMODE
 and
 CONTEXTLMTXMODE
 >
 0
 or
 fonts
.
handlers
.
typethree
3482
3483            for
 index
,
 subtable
 in
 sortedhash
(
shapes
)
 do
3484                if
 type
(
subtable
)
 =
=
 "
table
"
 then
3485                    local
 data
    =
 nil
3486                    local
 size
    =
 nil
3487                    local
 metrics
 =
 default
3488                    local
 format
  =
 subtable
.
format
3489                    local
 offset
  =
 subtable
.
offsets
[
index
]
3490                    setposition
(
f
,
offset
)
3491                    if
 format
 =
=
 17
 then
3492                        metrics
 =
 getsmallmetrics
(
f
)
3493                        size
    =
 true
3494                    elseif
 format
 =
=
 18
 then
3495                        metrics
 =
 getbigmetrics
(
f
)
3496                        size
    =
 true
3497                    elseif
 format
 =
=
 19
 then
3498                        metrics
 =
 subtable
.
metrics
3499                        size
    =
 true
3500                    else
3501                        -- forget about it
3502                    end
3503                    if
 size
 then
3504                        size
 =
 readulong
(
f
)
3505                        if
 delayed
 then
3506                            offset
 =
 getposition
(
f
)
3507                            data
   =
 nil
3508                        else
3509                            offset
 =
 nil
3510                            data
   =
 readstring
(
f
,
size
)
3511                            size
   =
 nil
3512                        end
3513                    else
3514                        offset
 =
 nil
3515                    end
3516                    local
 x
 =
 metrics
.
width
3517                    local
 y
 =
 metrics
.
height
3518                    shapes
[
index
]
 =
 {
3519                        x
    =
 x
,
3520                        y
    =
 y
,
3521                        o
    =
 offset
,
3522                        s
    =
 size
,
3523                        data
 =
 data
,
3524                    }
3525                    -- I'll look into this in more details when needed
3526                    -- as we can use the bearings to get better boxes.
3527                    local
 glyph
 =
 glyphs
[
index
]
3528                    if
 not
 glyph
.
boundingbox
 then
3529                        local
 width
  =
 glyph
.
width
3530                        local
 height
 =
 width
 *
 y
/
x
3531                        glyph
.
boundingbox
 =
 {
 0
,
 0
,
 width
,
 height
 }
3532                    end
3533                else
3534                    shapes
[
index
]
 =
 {
3535                        x
    =
 0
,
3536                        y
    =
 0
,
3537                        data
 =
 "
"
,
 -- or just nil
3538                    }
3539                end
3540            end
3541
3542            fontdata
.
pngshapes
 =
 shapes
 -- we cheat
3543        end
3544    end
3545
3546    function
 readers
.
cbdt
(
f
,
fontdata
,
specification
)
3547     -- local tableoffset = gotodatatable(f,fontdata,"ctdt",specification.glyphs)
3548     -- if tableoffset then
3549     --     local majorversion = readushort(f)
3550     --     local minorversion = readushort(f)
3551     -- end
3552    end
3553
3554    -- function readers.ebdt(f,fontdata,specification)
3555    --     if specification.glyphs then
3556    --     end
3557    -- end
3558
3559    -- function readers.ebsc(f,fontdata,specification)
3560    --     if specification.glyphs then
3561    --     end
3562    -- end
3563
3564    -- function readers.eblc(f,fontdata,specification)
3565    --     if specification.glyphs then
3566    --     end
3567    -- end
3568
3569end
3570
3571-- + AVAR : optional
3572-- + CFF2 : otf outlines
3573-- - CVAR : ttf hinting, not needed
3574-- + FVAR : the variations
3575-- + GVAR : ttf outline changes
3576-- + HVAR : horizontal changes
3577-- + MVAR : metric changes
3578-- + STAT : relations within fonts
3579-- * VVAR : vertical changes
3580--
3581-- * BASE : extra baseline adjustments
3582-- - GASP : not needed
3583-- + GDEF : not needed (carets)
3584-- + GPOS : adapted device tables (needed?)
3585-- + GSUB : new table
3586-- + NAME : 25 added
3587
3588function
 readers
.
stat
(
f
,
fontdata
,
specification
)
3589    local
 tableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
stat
"
,
true
)
 -- specification.variable
3590    if
 tableoffset
 then
3591        local
 extras
       =
 fontdata
.
extras
3592        local
 version
      =
 readulong
(
f
)
 -- 0x00010000
3593        local
 axissize
     =
 readushort
(
f
)
3594        local
 nofaxis
      =
 readushort
(
f
)
3595        local
 axisoffset
   =
 readulong
(
f
)
3596        local
 nofvalues
    =
 readushort
(
f
)
3597        local
 valuesoffset
 =
 readulong
(
f
)
3598        local
 fallbackname
 =
 extras
[
readushort
(
f
)
]
 -- beta fonts mess up
3599        local
 axis
         =
 {
 }
3600        local
 values
       =
 {
 }
3601        setposition
(
f
,
tableoffset
+
axisoffset
)
3602        for
 i
=
1
,
nofaxis
 do
3603            local
 tag
 =
 readtag
(
f
)
3604            axis
[
i
]
 =
 {
3605                tag
      =
 tag
,
3606                name
     =
 lower
(
extras
[
readushort
(
f
)
]
 or
 tag
)
,
3607                ordering
 =
 readushort
(
f
)
,
 -- maybe gaps
3608                variants
 =
 {
 }
3609            }
3610        end
3611        -- flags:
3612        --
3613        -- 0x0001 : OlderSiblingFontAttribute
3614        -- 0x0002 : ElidableAxisValueName
3615        -- 0xFFFC : reservedFlags
3616        --
3617        setposition
(
f
,
tableoffset
+
valuesoffset
)
3618        for
 i
=
1
,
nofvalues
 do
3619            values
[
i
]
 =
 readushort
(
f
)
3620        end
3621        for
 i
=
1
,
nofvalues
 do
3622            setposition
(
f
,
tableoffset
 +
 valuesoffset
 +
 values
[
i
]
)
3623            local
 format
  =
 readushort
(
f
)
3624            local
 index
   =
 readushort
(
f
)
 +
 1
3625            local
 flags
   =
 readushort
(
f
)
3626            local
 name
    =
 lower
(
extras
[
readushort
(
f
)
]
 or
 "
no name
"
)
3627            local
 value
   =
 readfixed
(
f
)
3628            local
 variant
3629            if
 format
 =
=
 1
 then
3630                variant
 =
 {
3631                    flags
 =
 flags
,
3632                    name
  =
 name
,
3633                    value
 =
 value
,
3634                }
3635            elseif
 format
 =
=
 2
 then
3636                variant
 =
 {
3637                    flags
   =
 flags
,
3638                    name
    =
 name
,
3639                    value
   =
 value
,
3640                    minimum
 =
 readfixed
(
f
)
,
3641                    maximum
 =
 readfixed
(
f
)
,
3642                }
3643            elseif
 format
 =
=
 3
 then
3644                variant
 =
 {
3645                    flags
 =
 flags
,
3646                    name
  =
 name
,
3647                    value
 =
 value
,
3648                    link
  =
 readfixed
(
f
)
,
3649                }
3650            end
3651            insert
(
axis
[
index
]
.
variants
,
variant
)
3652        end
3653        sort
(
axis
,
function
(
a
,
b
)
3654            return
 a
.
ordering
 <
 b
.
ordering
3655        end
)
3656        for
 i
=
1
,
#
axis
 do
3657            local
 a
 =
 axis
[
i
]
3658            sort
(
a
.
variants
,
function
(
a
,
b
)
3659                return
 a
.
name
 <
 b
.
name
3660            end
)
3661            a
.
ordering
 =
 nil
3662        end
3663        setvariabledata
(
fontdata
,
"
designaxis
"
,
axis
)
3664        setvariabledata
(
fontdata
,
"
fallbackname
"
,
fallbackname
)
3665    end
3666end
3667
3668-- The avar table is optional and used in combination with fvar. Given the
3669-- detailed explanation about bad values we expect the worst and do some
3670-- checking.
3671
3672function
 readers
.
avar
(
f
,
fontdata
,
specification
)
3673    local
 tableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
avar
"
,
true
)
 -- specification.variable
3674    if
 tableoffset
 then
3675
3676        local
 function
 collect
(
)
3677            local
 nofvalues
 =
 readushort
(
f
)
3678            local
 values
    =
 {
 }
3679            local
 lastfrom
  =
 false
3680            local
 lastto
    =
 false
3681            for
 i
=
1
,
nofvalues
 do
3682                local
 from
 =
 read2dot14
(
f
)
3683                local
 to
   =
 read2dot14
(
f
)
3684                if
 lastfrom
 and
 from
 <
=
 lastfrom
 then
3685                    -- ignore
3686                elseif
 lastto
 and
 to
 >
=
 lastto
 then
3687                    -- ignore
3688                else
3689                    values
[
#
values
+
1
]
 =
 {
 from
,
 to
 }
3690                    lastfrom
,
 lastto
 =
 from
,
 to
3691                end
3692            end
3693            nofvalues
 =
 #
values
3694            if
 nofvalues
 >
 2
 then
3695                local
 some
 =
 values
[
1
]
3696                if
 some
[
1
]
 =
=
 -1
 and
 some
[
2
]
 =
=
 -1
 then
3697                    some
 =
 values
[
nofvalues
]
3698                    if
 some
[
1
]
 =
=
 1
 and
 some
[
2
]
 =
=
 1
 then
3699                        for
 i
=
2
,
nofvalues
-1
 do
3700                            some
 =
 values
[
i
]
3701                            if
 some
[
1
]
 =
=
 0
 and
 some
[
2
]
 =
=
 0
 then
3702                                return
 values
3703                            end
3704                        end
3705                    end
3706                end
3707            end
3708            return
 false
3709        end
3710
3711        local
 version
  =
 readulong
(
f
)
 -- 0x00010000
3712        local
 reserved
 =
 readushort
(
f
)
3713        local
 nofaxis
  =
 readushort
(
f
)
3714        local
 segments
 =
 {
 }
3715        for
 i
=
1
,
nofaxis
 do
3716            segments
[
i
]
 =
 collect
(
)
3717        end
3718        setvariabledata
(
fontdata
,
"
segments
"
,
segments
)
3719    end
3720end
3721
3722function
 readers
.
fvar
(
f
,
fontdata
,
specification
)
3723    local
 tableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
fvar
"
,
true
)
 -- specification.variable or specification.instancenames
3724    if
 tableoffset
 then
3725        local
 version
         =
 readulong
(
f
)
 -- 0x00010000
3726        local
 offsettoaxis
    =
 tableoffset
 +
 readushort
(
f
)
3727        local
 reserved
        =
 skipshort
(
f
)
3728        -- pair 1
3729        local
 nofaxis
         =
 readushort
(
f
)
3730        local
 sizeofaxis
      =
 readushort
(
f
)
3731        -- pair 2
3732        local
 nofinstances
    =
 readushort
(
f
)
3733        local
 sizeofinstances
 =
 readushort
(
f
)
3734        --
3735        local
 extras
    =
 fontdata
.
extras
3736        local
 axis
      =
 {
 }
3737        local
 instances
 =
 {
 }
3738        --
3739        setposition
(
f
,
offsettoaxis
)
3740        --
3741        for
 i
=
1
,
nofaxis
 do
3742            axis
[
i
]
 =
 {
3743                tag
     =
 readtag
(
f
)
,
   -- ital opsz slnt wdth wght
3744                minimum
 =
 readfixed
(
f
)
,
3745                default
 =
 readfixed
(
f
)
,
3746                maximum
 =
 readfixed
(
f
)
,
3747                flags
   =
 readushort
(
f
)
,
3748                name
    =
 lower
(
extras
[
readushort
(
f
)
]
 or
 "
bad name
"
)
,
3749            }
3750            local
 n
 =
 sizeofaxis
 -
 20
3751            if
 n
 >
 0
 then
3752                skipbytes
(
f
,
n
)
3753            elseif
 n
 <
 0
 then
3754                -- error
3755            end
3756        end
3757        --
3758        local
 nofbytes
   =
 2
 +
 2
 +
 2
 +
 nofaxis
 *
 4
3759        local
 readpsname
 =
 nofbytes
 <
=
 sizeofinstances
3760        local
 skippable
  =
 sizeofinstances
 -
 nofbytes
3761        for
 i
=
1
,
nofinstances
 do
3762            local
 subfamid
 =
 readushort
(
f
)
3763            local
 flags
    =
 readushort
(
f
)
 -- 0, not used yet
3764            local
 values
   =
 {
 }
3765            for
 i
=
1
,
nofaxis
 do
3766                values
[
i
]
 =
 {
3767                    axis
  =
 axis
[
i
]
.
tag
,
3768                    value
 =
 readfixed
(
f
)
,
3769                }
3770            end
3771            local
 psnameid
 =
 readpsname
 and
 readushort
(
f
)
 or
 0xFFFF
3772            if
 subfamid
 =
=
 2
 or
 subfamid
 =
=
 17
 then
3773                -- okay
3774            elseif
 subfamid
 =
=
 0xFFFF
 then
3775                subfamid
 =
 nil
3776            elseif
 subfamid
 <
=
 256
 or
 subfamid
 >
=
 32768
 then
3777                subfamid
 =
 nil
 -- actually an error
3778            end
3779            if
 psnameid
 =
=
 6
 then
3780                -- okay
3781            elseif
 psnameid
 =
=
 0xFFFF
 then
3782                psnameid
 =
 nil
3783            elseif
 psnameid
 <
=
 256
 or
 psnameid
 >
=
 32768
 then
3784                psnameid
 =
 nil
 -- actually an error
3785            end
3786            instances
[
i
]
 =
 {
3787             -- flags     = flags,
3788                subfamily
 =
 extras
[
subfamid
]
,
3789                psname
    =
 psnameid
 and
 extras
[
psnameid
]
 or
 nil
,
3790                values
    =
 values
,
3791            }
3792            if
 skippable
 >
 0
 then
3793                skipbytes
(
f
,
skippable
)
3794            end
3795        end
3796        setvariabledata
(
fontdata
,
"
axis
"
,
axis
)
3797        setvariabledata
(
fontdata
,
"
instances
"
,
instances
)
3798    end
3799end
3800
3801function
 readers
.
hvar
(
f
,
fontdata
,
specification
)
3802    local
 factors
 =
 specification
.
factors
3803    if
 not
 factors
 then
3804        return
3805    end
3806    local
 tableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
hvar
"
,
specification
.
variable
)
3807    if
 not
 tableoffset
 then
3808        return
3809    end
3810
3811    local
 version
         =
 readulong
(
f
)
 -- 0x00010000
3812    local
 variationoffset
 =
 tableoffset
 +
 readulong
(
f
)
 -- the store
3813    local
 advanceoffset
   =
 tableoffset
 +
 readulong
(
f
)
3814    local
 lsboffset
       =
 tableoffset
 +
 readulong
(
f
)
3815    local
 rsboffset
       =
 tableoffset
 +
 readulong
(
f
)
3816
3817    local
 regions
    =
 {
 }
3818    local
 variations
 =
 {
 }
3819    local
 innerindex
 =
 {
 }
 -- size is mapcount
3820    local
 outerindex
 =
 {
 }
 -- size is mapcount
3821
3822    if
 variationoffset
 >
 0
 then
3823        regions
,
 deltas
 =
 readvariationdata
(
f
,
variationoffset
,
factors
)
3824    end
3825
3826    if
 not
 regions
 then
3827        -- for now .. what to do ?
3828        return
3829    end
3830
3831    if
 advanceoffset
 >
 0
 then
3832        --
3833        -- innerIndexBitCountMask = 0x000F
3834        -- mapEntrySizeMask       = 0x0030
3835        -- reservedFlags          = 0xFFC0
3836        --
3837        -- outerIndex = entry >>       ((entryFormat & innerIndexBitCountMask) + 1)
3838        -- innerIndex = entry & ((1 << ((entryFormat & innerIndexBitCountMask) + 1)) - 1)
3839        --
3840        setposition
(
f
,
advanceoffset
)
3841        local
 format
       =
 readushort
(
f
)
 -- todo: check
3842        local
 mapcount
     =
 readushort
(
f
)
3843        local
 entrysize
    =
 rshift
(
band
(
format
,
0x0030
)
,
4
)
 +
 1
3844        local
 nofinnerbits
 =
 band
(
format
,
0x000F
)
 +
 1
 -- n of inner bits
3845        local
 innermask
    =
 lshift
(
1
,
nofinnerbits
)
 -
 1
3846        local
 readcardinal
 =
 read_cardinal
[
entrysize
]
 -- 1 upto 4 bytes
3847        for
 i
=
0
,
mapcount
-1
 do
3848            local
 mapdata
 =
 readcardinal
(
f
)
3849            outerindex
[
i
]
 =
 rshift
(
mapdata
,
nofinnerbits
)
3850            innerindex
[
i
]
 =
 band
(
mapdata
,
innermask
)
3851        end
3852        -- use last entry when no match i
3853        setvariabledata
(
fontdata
,
"
hvarwidths
"
,
true
)
3854        local
 glyphs
 =
 fontdata
.
glyphs
3855        for
 i
=
0
,
fontdata
.
nofglyphs
-1
 do
3856            local
 glyph
 =
 glyphs
[
i
]
3857            local
 width
 =
 glyph
.
width
3858            if
 width
 then
3859                local
 outer
 =
 outerindex
[
i
]
 or
 0
3860                local
 inner
 =
 innerindex
[
i
]
 or
 i
3861                if
 outer
 and
 inner
 then
 -- not needed
3862                    local
 delta
 =
 deltas
[
outer
+
1
]
3863                    if
 delta
 then
3864                        local
 d
 =
 delta
.
deltas
[
inner
+
1
]
3865                        if
 d
 then
3866                            local
 scales
 =
 delta
.
scales
3867                            local
 deltaw
 =
 0
3868                            for
 i
=
1
,
#
scales
 do
3869                                local
 di
 =
 d
[
i
]
3870                                if
 di
 then
3871                                    deltaw
 =
 deltaw
 +
 scales
[
i
]
 *
 di
3872                                else
3873                                    break
 -- can't happen
3874                                end
3875                            end
3876-- report("index: %i, outer: %i, inner: %i, deltas: %|t, scales: %|t, width: %i, delta %i",
3877--     i,outer,inner,d,scales,width,round(deltaw))
3878                            glyph
.
width
 =
 width
 +
 round
(
deltaw
)
3879                        end
3880                    end
3881                end
3882            end
3883        end
3884
3885    end
3886
3887 -- if lsboffset > 0 then
3888 --     -- we don't use left side bearings
3889 -- end
3890
3891 -- if rsboffset > 0 then
3892 --     -- we don't use right side bearings
3893 -- end
3894
3895 -- setvariabledata(fontdata,"hregions",regions)
3896
3897end
3898
3899function
 readers
.
vvar
(
f
,
fontdata
,
specification
)
3900    if
 not
 specification
.
variable
 then
3901        return
3902    end
3903end
3904
3905function
 readers
.
mvar
(
f
,
fontdata
,
specification
)
3906    local
 tableoffset
 =
 gotodatatable
(
f
,
fontdata
,
"
mvar
"
,
specification
.
variable
)
3907    if
 tableoffset
 then
3908        local
 version
       =
 readulong
(
f
)
 -- 0x00010000
3909        local
 reserved
      =
 skipshort
(
f
,
1
)
3910        local
 recordsize
    =
 readushort
(
f
)
3911        local
 nofrecords
    =
 readushort
(
f
)
3912        local
 offsettostore
 =
 tableoffset
 +
 readushort
(
f
)
3913        local
 dimensions
    =
 {
 }
3914        local
 factors
       =
 specification
.
factors
3915        if
 factors
 then
3916            local
 regions
,
 deltas
 =
 readvariationdata
(
f
,
offsettostore
,
factors
)
3917            for
 i
=
1
,
nofrecords
 do
3918                local
 tag
 =
 readtag
(
f
)
3919                local
 var
 =
 variabletags
[
tag
]
3920                if
 var
 then
3921                    local
 outer
 =
 readushort
(
f
)
3922                    local
 inner
 =
 readushort
(
f
)
3923                    local
 delta
 =
 deltas
[
outer
+
1
]
3924                    if
 delta
 then
3925                        local
 d
 =
 delta
.
deltas
[
inner
+
1
]
3926                        if
 d
 then
3927                            local
 scales
 =
 delta
.
scales
3928                            local
 dd
 =
 0
3929                            for
 i
=
1
,
#
scales
 do
3930                                dd
 =
 dd
 +
 scales
[
i
]
 *
 d
[
i
]
3931                            end
3932                            var
(
fontdata
,
round
(
dd
)
)
3933                        end
3934                    end
3935                else
3936                    skipshort
(
f
,
2
)
3937                end
3938                if
 recordsize
 >
 8
 then
 -- 4 + 2 + 2
3939                    skipbytes
(
recordsize
-8
)
3940                end
3941            end
3942        end
3943     -- setvariabledata(fontdata,"mregions",regions)
3944    end
3945end
3946
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