ref: 8918bd598190b8c467746524f1886cc40be0b617
dir: /sys/lib/postscript/prologues/shade.ps/
% % Shading support - primarily for ASCII file translators. % /grays [0.98 0.9 0.75 0.6] def /setshade { /level exch def level 0 le { /textgray 0 def /backgray 1 def }{ /backgray level grays length gt {/textgray 1 def 0} {/textgray 0 def grays level 1 sub get} ifelse def } ifelse textgray setgray /dY1 0 def /dY2 0 def } bind def /drawrvbox { /x2 exch charwidth mul def /x1 exch charwidth mul def x1 x2 lt { dup % expects y on top /y1 exch linespace mul def /y2 y1 def dY1 0 eq dY2 0 eq and { currentfont /FontBBox get aload pop 160 sub currentfont /FontMatrix get dtransform /dY2 exch def pop 100 add currentfont /FontMatrix get dtransform /dY1 exch def pop } if /y1 y1 dY1 add def /y2 y2 dY2 add def backgray setgray newpath x1 y1 moveto x2 y1 lineto x2 y2 lineto x1 y2 lineto closepath fill } if textgray setgray } bind def