| 1 |
#ifndef lint
|
| 2 |
static const char RCSid[] = "$Id: p_func.c,v 2.7 2004/03/30 16:13:01 schorsch Exp $";
|
| 3 |
#endif
|
| 4 |
/*
|
| 5 |
* p_func.c - routine for procedural patterns.
|
| 6 |
*/
|
| 7 |
|
| 8 |
#include "copyright.h"
|
| 9 |
|
| 10 |
#include "ray.h"
|
| 11 |
#include "func.h"
|
| 12 |
#include "rtotypes.h"
|
| 13 |
|
| 14 |
/*
|
| 15 |
* A procedural pattern can either be a brightness or a
|
| 16 |
* color function. A brightness function is given as:
|
| 17 |
*
|
| 18 |
* modifier brightfunc name
|
| 19 |
* 2+ bvarname filename xf
|
| 20 |
* 0
|
| 21 |
* n A1 A2 ..
|
| 22 |
*
|
| 23 |
* A color function is given as:
|
| 24 |
*
|
| 25 |
* modifier colorfunc name
|
| 26 |
* 4+ rvarname gvarname bvarname filename xf
|
| 27 |
* 0
|
| 28 |
* n A1 A2 ..
|
| 29 |
*
|
| 30 |
* Filename is the name of the file where the variable definitions
|
| 31 |
* can be found. The list of real arguments can be accessed by
|
| 32 |
* definitions in the file. The xf is a transformation
|
| 33 |
* to get from the original coordinates to the current coordinates.
|
| 34 |
*/
|
| 35 |
|
| 36 |
|
| 37 |
int
|
| 38 |
p_bfunc( /* compute brightness pattern */
|
| 39 |
OBJREC *m,
|
| 40 |
RAY *r
|
| 41 |
)
|
| 42 |
{
|
| 43 |
double bval;
|
| 44 |
MFUNC *mf;
|
| 45 |
|
| 46 |
if (m->oargs.nsargs < 2)
|
| 47 |
objerror(m, USER, "bad # arguments");
|
| 48 |
mf = getfunc(m, 1, 0x1, 0);
|
| 49 |
setfunc(m, r);
|
| 50 |
errno = 0;
|
| 51 |
bval = evalue(mf->ep[0]);
|
| 52 |
if (errno == EDOM || errno == ERANGE) {
|
| 53 |
objerror(m, WARNING, "compute error");
|
| 54 |
return(0);
|
| 55 |
}
|
| 56 |
scalecolor(r->pcol, bval);
|
| 57 |
return(0);
|
| 58 |
}
|
| 59 |
|
| 60 |
|
| 61 |
int
|
| 62 |
p_cfunc( /* compute color pattern */
|
| 63 |
OBJREC *m,
|
| 64 |
RAY *r
|
| 65 |
)
|
| 66 |
{
|
| 67 |
COLOR cval;
|
| 68 |
MFUNC *mf;
|
| 69 |
|
| 70 |
if (m->oargs.nsargs < 4)
|
| 71 |
objerror(m, USER, "bad # arguments");
|
| 72 |
mf = getfunc(m, 3, 0x7, 0);
|
| 73 |
setfunc(m, r);
|
| 74 |
errno = 0;
|
| 75 |
setcolor(cval, evalue(mf->ep[0]),
|
| 76 |
evalue(mf->ep[1]),
|
| 77 |
evalue(mf->ep[2]));
|
| 78 |
if (errno == EDOM || errno == ERANGE) {
|
| 79 |
objerror(m, WARNING, "compute error");
|
| 80 |
return(0);
|
| 81 |
}
|
| 82 |
multcolor(r->pcol, cval);
|
| 83 |
return(0);
|
| 84 |
}
|
