POV-Ray : Newsgroups : povray.advanced-users : Help with eval_pigment : Help with eval_pigment Server Time
29 Jul 2024 12:27:22 EDT (-0400)
  Help with eval_pigment  
From: Alf Peake
Date: 11 Mar 2002 18:46:35
Message: <3c8d41db$1@news.povray.org>
v3.5 question.

The docs say that eval_pigment() evaluates the color of a pigment. Am
I wrong in treating this as a vector?  If not, what am I doing here
that annoys vlength() or sqrt(vdot(,)) in 3.5? It worked fine in
MegaPov 0.7.

I'm using WinPOV-Ray 3.5b12, Win98SE, Celeron 500 and 160MB.

Alf

--8<---------8<---------

#include "functions.inc" // Remove this line in MegaPov
#declare Map9 = pigment{ image_map{ png "test"} }
#declare Pig9 = eval_pigment( pigment{ Map9 }, <0.5, 0.5, 0>);
//#declare Pig9 = <0.5, 0.6, 0.7>; // This line is OK

// Next line is OK and also using Pig9.green
#debug concat( "\n .y = ", str( Pig9.y, 0, 3),"\n" )
// Next is OK in MegaPov 0.7 but not in Pov 3.5
#debug concat( " vlength = ",str( vlength( Pig9 ), 0, 3),"\n" )

sphere{0,0 pigment{ rgb 0 } } // Kills "no objects ..."

/*
Pov 3.5 Error message, cursor stops on "9":
#debug concat( " vlength = ",str( vlength( Pig9 ) <----ERROR
Parse Error: Vector expected but color expression found.
*/


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