1%D \module 2%D [ file=meta-imp-clp, 3%D version=2000.07.06, 4%D title=\METAPOST\ Graphics, 5%D subtitle=Clipping, 6%D author=Hans Hagen, 7%D date=\currentdate, 8%D copyright={PRAGMA ADE \& \CONTEXT\ Development Team}] 9%C 10%C This module is part of the \CONTEXT\ macro||package and is 11%C therefore copyrighted by \PRAGMA. See mreadme.pdf for 12%C details. 13 14%D In this library, we define a bunch of clipping paths that 15%D can be fed to \type {\clip}. 16 17\startMPclip{ellipse} 18 clip currentpicture to unitcircle 19 xscaled \width yscaled \height ; 20\stopMPclip 21 22\startMPclip{negellipse} 23 clip currentpicture to (unitcircle peepholed unitsquare) 24 xscaled \width yscaled \height ; 25\stopMPclip 26 27\startMPclip{urellipse} 28 clip currentpicture to urcircle scaled 2 29 xscaled \width yscaled \height ; 30\stopMPclip 31 32\startMPclip{ulellipse} 33 clip currentpicture to ulcircle scaled 2 shifted (1,0) 34 xscaled \width yscaled \height ; 35\stopMPclip 36 37\startMPclip{llellipse} 38 clip currentpicture to llcircle scaled 2 shifted (1,1) 39 xscaled \width yscaled \height ; 40\stopMPclip 41 42\startMPclip{lrellipse} 43 clip currentpicture to lrcircle scaled 2 shifted (0,1) 44 xscaled \width yscaled \height ; 45\stopMPclip 46 47\startMPclip{tellipse} 48 clip currentpicture to tcircle shifted (.5,0) yscaled 2 49 xscaled \width yscaled \height ; 50\stopMPclip 51 52\startMPclip{bellipse} 53 clip currentpicture to bcircle shifted (.5,.5) yscaled 2 54 xscaled \width yscaled \height ; 55\stopMPclip 56 57\startMPclip{lellipse} 58 clip currentpicture to lcircle shifted (.5,.5) xscaled 2 59 xscaled \width yscaled \height ; 60\stopMPclip 61 62\startMPclip{rellipse} 63 clip currentpicture to rcircle shifted (0,.5) xscaled 2 64 xscaled \width yscaled \height ; 65\stopMPclip 66 67\startMPclip{diamond} 68 clip currentpicture to unitdiamond 69 xscaled \width yscaled \height ; 70\stopMPclip 71 72\startMPclip{negdiamond} 73 clip currentpicture to (unitdiamond peepholed unitsquare) 74 xscaled \width yscaled \height ; 75\stopMPclip 76 77\startMPclip{urtriangle} 78 clip currentpicture to urtriangle scaled 2 79 xscaled \width yscaled \height ; 80\stopMPclip 81 82\startMPclip{ultriangle} 83 clip currentpicture to ultriangle scaled 2 shifted (1,0) 84 xscaled \width yscaled \height ; 85\stopMPclip 86 87\startMPclip{lltriangle} 88 clip currentpicture to lltriangle scaled 2 shifted (1,1) 89 xscaled \width yscaled \height ; 90\stopMPclip 91 92\startMPclip{lrtriangle} 93 clip currentpicture to lrtriangle scaled 2 shifted (0,1) 94 xscaled \width yscaled \height ; 95\stopMPclip 96 97% More efficient: 98% 99% \def\dosimpleMPclip#1 100% {clip currentpicture to (#1) xscaled \width yscaled \height ;} 101% 102% \def\simpleMPclip#1#2% 103% {\startMPclip{#1}\dosimpleMPclip{#2}\stopMPclip} 104% 105% \simpleMPclip {ellipse} {unitcircle} 106% \simpleMPclip {diamond} {unitdiamond} 107% 108% \simpleMPclip {negellipse} {unitcircle peepholed unitsquare} 109% \simpleMPclip {negdiamond} {unitdiamond peepholed unitsquare} 110% 111% \simpleMPclip {urellipse} {urcircle scaled 2 shifted (0,0)} 112% \simpleMPclip {ulellipse} {ulcircle scaled 2 shifted (1,0)} 113% \simpleMPclip {llellipse} {llcircle scaled 2 shifted (1,1)} 114% \simpleMPclip {lrellipse} {lrcircle scaled 2 shifted (0,1)} 115% 116% \simpleMPclip {tellipse} {tcircle shifted (.5,0) yscaled 2} 117% \simpleMPclip {bellipse} {bcircle shifted (.5,.5) yscaled 2} 118% \simpleMPclip {lellipse} {lcircle shifted (.5,.5) xscaled 2} 119% \simpleMPclip {rellipse} {rcircle shifted (0,.5) xscaled 2} 120% 121% \simpleMPclip {urtriangle} {urtriangle scaled 2 shifted (0,0)} 122% \simpleMPclip {ultriangle} {ultriangle scaled 2 shifted (1,0)} 123% \simpleMPclip {lltriangle} {lltriangle scaled 2 shifted (1,1)} 124% \simpleMPclip {lrtriangle} {lrtriangle scaled 2 shifted (0,1)} 125 126%D \in {Figure} [fig:clipping paths] shows which paths are 127%D predefined. When applied to a whole picture, their usage 128%D is: 129%D 130%D \starttyping 131%D \clip[nx=1,ny=1,mp=ellipse]{some clippable content} 132%D \stoptyping 133%D 134%D \startbuffer 135%D \setupclipping [nx=1,ny=1,x=1,y=1] 136%D \setupblackrules[width=2cm,height=1cm] 137%D \startcombination[6*3] % \startcombination[6*3] 138%D {\clip[mp=urellipse] {\blackrule}} {urellipse} 139%D {\clip[mp=ulellipse] {\blackrule}} {ulellipse} 140%D {\clip[mp=llellipse] {\blackrule}} {llellipse} 141%D {\clip[mp=lrellipse] {\blackrule}} {lrellipse} 142%D {\clip[mp=ellipse] {\blackrule}} {ellipse} 143%D {\clip[mp=negellipse]{\blackrule}} {negellipse} 144%D {\clip[mp=tellipse] {\blackrule}} {tellipse} 145%D {\clip[mp=bellipse] {\blackrule}} {bellipse} 146%D {\clip[mp=lellipse] {\blackrule}} {lellipse} 147%D {\clip[mp=rellipse] {\blackrule}} {rellipse} 148%D {} {} 149%D {} {} 150%D {\clip[mp=urtriangle]{\blackrule}} {urtriangle} 151%D {\clip[mp=ultriangle]{\blackrule}} {ultriangle} 152%D {\clip[mp=lltriangle]{\blackrule}} {lltriangle} 153%D {\clip[mp=lrtriangle]{\blackrule}} {lrtriangle} 154%D {\clip[mp=diamond] {\blackrule}} {diamond} 155%D {\clip[mp=negdiamond]{\blackrule}} {negdiamond} 156%D \stopcombination % \stopcombination 157%D \stopbuffer 158%D 159%D \placefigure % \placefigure 160%D [here][fig:clipping paths] 161%D {The predefined clipping paths.} 162%D {\getbuffer} % {\getbuffer} 163 164\endinput 165 |
