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/* Copyright (c) 1986 Regents of the University of California */ |
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|
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#ifndef lint |
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static char SCCSid[] = "$SunId$ LBL"; |
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#endif |
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|
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/* |
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* p_func.c - routine for procedural patterns. |
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* |
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* 4/8/86 |
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*/ |
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|
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#include "ray.h" |
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|
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/* |
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* A procedural pattern can either be a brightness or a |
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* color function. A brightness function is given as: |
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* |
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* modifier brightfunc name |
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* 2+ bvarname filename xf |
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* 0 |
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* n A1 A2 .. |
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* |
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* A color function is given as: |
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* |
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* modifier colorfunc name |
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* 4+ rvarname gvarname bvarname filename xf |
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* 0 |
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* n A1 A2 .. |
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* |
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* Filename is the name of the file where the variable definitions |
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* can be found. The list of real arguments can be accessed by |
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* definitions in the file. The xf is a transformation |
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* to get from the original coordinates to the current coordinates. |
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*/ |
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|
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|
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p_bfunc(m, r) /* compute brightness pattern */ |
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register OBJREC *m; |
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RAY *r; |
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{ |
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extern double varvalue(); |
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extern int errno; |
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double bval; |
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register char **sa; |
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|
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setfunc(m, r); |
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|
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sa = m->oargs.sarg; |
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|
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if (m->oargs.nsargs < 2) |
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objerror(m, USER, "bad # arguments"); |
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if (!vardefined(sa[0])) |
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loadfunc(sa[1]); |
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errno = 0; |
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bval = varvalue(sa[0]); |
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if (errno) { |
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objerror(m, WARNING, "compute error"); |
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return; |
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} |
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scalecolor(r->pcol, bval); |
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} |
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|
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|
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p_cfunc(m, r) /* compute color pattern */ |
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register OBJREC *m; |
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RAY *r; |
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{ |
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extern double varvalue(); |
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extern int errno; |
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COLOR cval; |
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register char **sa; |
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|
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setfunc(m, r); |
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|
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sa = m->oargs.sarg; |
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|
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if (m->oargs.nsargs < 4) |
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objerror(m, USER, "bad # arguments"); |
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if (!vardefined(sa[0])) |
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loadfunc(sa[3]); |
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errno = 0; |
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setcolor(cval, varvalue(sa[0]), |
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varvalue(sa[1]), |
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varvalue(sa[2])); |
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if (errno) { |
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objerror(m, WARNING, "compute error"); |
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return; |
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} |
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multcolor(r->pcol, cval); |
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} |
