MetaFun - Pragma ADE

fill p shifted (3cm,0) withcolor .5blue ;
fill p shifted (6cm,0) withcolor transparent (1,0.5,blue) ;
fill p shifted (9cm,0) withcolor .5[blue,white] ;
The next series demonstrates that we use the complementary factor .7 in the METAPOST soft color
to achieve the same softness as the .3 transparency.
path p ; p := fullcircle scaled 2cm ;
fill p shifted (0cm,0) withcolor red ;
fill p shifted (3cm,0) withcolor .7red ;
fill p shifted (6cm,0) withcolor transparent (1,0.3,red) ;
fill p shifted (9cm,0) withcolor .7[red,white] ;
So far we have applied transparent colors to shapes but text can also be the target. The following
works okay in MKII.
vardef SampleText (expr t, c) =
save p ; picture p ;
p := image (draw t infont "\truefontname{Regular}") ;
draw (p shifted (- xpart center p,0)) scaled 5 withcolor c;
enddef ;
SampleText ("Much Of This" , transparent(1, .5, red )) ;
SampleText ("Functionality" , transparent(1, .5, green)) ;
SampleText ("Was Written" , transparent(1, .5, blue )) ;
SampleText ("While Listening", transparent(1, .5, cmyk(1,0,0,0))) ;
SampleText ("To the CD's Of" , transparent(1, .5, cmyk(0,1,0,0))) ;
SampleText ("Tori Amos" , transparent(1, .5, cmyk(0,0,1,0))) ;
The source code of this example illustrates that the CMYK color space is also supported. The
\truefontname macro communicates the running font from TEX to METAPOST. Instead of such low
level code one can of course also use the textext macro.
However, as we do the typesetting in TEX in MKIV this is the way to go:
vardef SampleText (expr t) =
draw textext(t) scaled 5 ;
enddef ;
Transparency Special effects
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