1if not modules then modules = { } end modules ['grph-bmp'] = { 2 version = 1.001, 3 comment = "companion to grph-inc.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 9local random = math.random 10local context = context 11 12local report_bitmap = logs.reporter("graphics","bitmap") 13 14local bitmaps = { } 15graphics.bitmaps = bitmaps 16 17local wrapimage = images.wrap 18 19function bitmaps.new(xsize,ysize,colorspace,colordepth,mask,index) 20 if not xsize or not ysize or xsize == 0 or ysize == 0 then 21 report_bitmap("provide 'xsize' and 'ysize' larger than zero") 22 return 23 end 24 if not colorspace then 25 report_bitmap("provide 'colorspace' (1, 2, 3, 'gray', 'rgb', 'cmyk'") 26 return 27 end 28 if not colordepth then 29 report_bitmap("provide 'colordepth' (1, 2)") 30 return 31 end 32 return graphics.identifiers.bitmap { 33 colorspace = colorspace, 34 colordepth = colordepth, 35 xsize = xsize, 36 ysize = ysize, 37 mask = mask and true or nil, 38 index = index and true or nil, 39 } 40end 41 42local function flush(bitmap) 43 local specification = backends.codeinjections.bitmap(bitmap) 44 if specification then 45 return wrapimage(specification) 46 end 47end 48 49bitmaps.flush = flush 50 51function bitmaps.tocontext(bitmap,width,height) 52 local bmp = flush(bitmap) 53 if bmp then 54 if type(width) == "number" then 55 width = width .. "sp" 56 end 57 if type(height) == "number" then 58 height = height .. "sp" 59 end 60 if width or height then 61 context.scale ( 62 { 63 width = width, 64 height = height, 65 }, 66 bmp 67 ) 68 else 69 context(bmp) 70 end 71 end 72end 73 74local function placeholder(nx,ny) 75 76 local nx = nx or 8 77 local ny = ny or nx 78 local bitmap = bitmaps.new(nx,ny,"gray",1) 79 local data = bitmap.data 80 81 for i=1,ny do 82 local d = data[i] 83 for j=1,nx do 84 d[j] = random(100,199) 85 end 86 end 87 88 return backends.codeinjections.bitmap(bitmap) 89 90end 91 92bitmaps.placeholder = placeholder 93 |
