On Sat, Nov 1, 2008 at 1:38 AM, Renaud Aubin <aubin@nibua-r.org> wrote:

I have some trouble using a gradient background (solid) with a
transparent element :

   def test_shade (expr a, b) =
   pickup pencircle scaled 1mm ;
   color ca ; ca := \MPcolor{a} ;
   color cb ; cb := \MPcolor{b} ;
   color cc ; cc := \MPcolor{c} ;
   sh := define_linear_shade(origin
shifted(0cm,.5*\overlayheight),origin,ca,cb) ;
   fill fullsquare xscaled \overlaywidth yscaled \overlayheight
withshade sh;
   draw origin withcolor cc;
   draw origin shifted(0cm,-.25*\overlayheight) withcolor cc;
   enddef ;


   test_shade(origin, origin shifted(0cm,1cm));
   draw fullcircle scaled 10cm shifted (0cm,0.25*\overlayheight)
withcolor transparent(1,0.5,white) withpen pencircle scaled 2cm;

%%%%%%%% If you comment out the previous line the color rendering is
definitelly different...


 \input knuth


This is my test.
Where is the problem ?

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