Subject: Re: [pstricks] Gouraud shading

[Eugene K. Ressler]

> From: Herbert Voss <LaTeX at zedat.fu-berlin.de>
> >There is a PS code example at
> >
> >http://www.math.ubc.ca/~cass/graphics/manual/
> in which part ?

Chapter 14, page 13.  Included below.  This PS draws a triangle with
shading interpolated among red, black, and white.  A syntax like the
following would be nice

\gouraudtriangle[options...](0,.866){1,0,0}(-.5,0){1,1,1}(.5,0){0,0,0}

or alternately (but not very good for many purposes including mine
because you might end up defining many, many colors)

\gouraudtriangle[options...](0,.866){red}(-.5,0){white}(.5,0){black}

Thanks for the consideration.

Gene

/A [ 0 3 sqrt 2 div ] def
/B [ -0.5 0 ] def
/C [ 0.5 0 ] def
/ds [
0 A aload pop 1 0 0
0 B aload pop 1 1 1
0 C aload pop 0 0 0
] def
newpath
<<
/ShadingType 4
/ColorSpace [ /DeviceRGB ]
/DataSource ds
>>
shfill