src/rt/m_direct.c

/* Copyright (c) 1991 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "$SunId$ LBL";
#endif

/*
 * Routines for light-redirecting materials and
 *   their associated virtual light sources
 */

#include  "ray.h"

#include  "otypes.h"

#include  "source.h"

/*
 * The arguments for MAT_DIRECT1 are:
 *
 *      5+ coef1 dx1 dy1 dz1 funcfile transform..
 *      0
 *      n A1 A2 .. An
 *
 * The arguments for MAT_DIRECT2 are:
 *
 *      9+ coef1 dx1 dy1 dz1 coef2 dx2 dy2 dz2 funcfile transform..
 *      0
 *      n A1 A2 .. An
 */


extern double  varvalue();

int  dir_proj();
VSMATERIAL  direct1_vs = {dir_proj, 1};
VSMATERIAL  direct2_vs = {dir_proj, 2};


m_direct(m, r)                  /* shade redirected ray */
register OBJREC  *m;
register RAY  *r;
{
                                        /* check if source ray */
        if (r->rsrc >= 0 && source[r->rsrc].so != r->ro)
                return;                         /* got the wrong guy */
        dir_check(m);
                                        /* compute first projection */
        if (m->otype == MAT_DIRECT1 ||
                        (r->rsrc < 0 || source[r->rsrc].sa.sv.pn == 0))
                redirect(m, r, 0);
                                        /* compute second projection */
        if (m->otype == MAT_DIRECT2 &&
                        (r->rsrc < 0 || source[r->rsrc].sa.sv.pn == 1))
                redirect(m, r, 1);
}


redirect(m, r, n)               /* compute n'th ray redirection */
OBJREC  *m;
RAY  *r;
int  n;
{
        register char  **sa;
        RAY  nr;
        double  coef;
        register int  j;
                                        /* set up function */
        setfunc(m, r);
        sa = m->oargs.sarg + 4*n;
                                        /* compute coefficient */
        errno = 0;
        coef = varvalue(sa[0]);
        if (errno)
                goto computerr;
        if (coef <= FTINY || rayorigin(&nr, r, TRANS, coef) < 0)
                return(0);
                                        /* compute direction */
        errno = 0;
        for (j = 0; j < 3; j++)
                nr.rdir[j] = varvalue(sa[j+1]);
        if (errno || normalize(nr.rdir) == 0.0)
                goto computerr;
                                        /* compute value */
        if (r->rsrc >= 0)
                nr.rsrc = source[r->rsrc].sa.sv.sn;
        rayvalue(&nr);
        scalecolor(nr.rcol, coef);
        addcolor(r->rcol, nr.rcol);
        return(1);
computerr:
        objerror(m, WARNING, "compute error");
        return(-1);
}


dir_proj(pm, o, s, n)           /* compute a director's projection */
MAT4  pm;
OBJREC  *o;
SRCREC  *s;
int  n;
{
        RAY  tr;
        register OBJREC  *m;
        char  **sa;
        FVECT  cent, newdir, nv, h;
        double  olddot, newdot, od;
        register int  i, j;
                                /* get material arguments */
        m = objptr(o->omod);
        dir_check(m);
        sa = m->oargs.sarg + 4*n;
                                /* initialize test ray */
        getmaxdisk(cent, o);
        if (s->sflags & SDISTANT)
                for (i = 0; i < 3; i++) {
                        tr.rdir[i] = -s->sloc[i];
                        tr.rorg[i] = cent[i] - tr.rdir[i];
                }
        else {
                for (i = 0; i < 3; i++) {
                        tr.rdir[i] = cent[i] - s->sloc[i];
                        tr.rorg[i] = s->sloc[i];
                }
                if (normalize(tr.rdir) == 0.0)
                        return(0);              /* at source! */
        }
        od = getplaneq(nv, o);
        olddot = DOT(tr.rdir, nv);
        if (olddot <= FTINY && olddot >= -FTINY)
                return(0);              /* old dir parallels plane */
        rayorigin(&tr, NULL, PRIMARY, 1.0);
        if (!(*ofun[o->otype].funp)(o, &tr))
                return(0);              /* no intersection! */
                                /* compute redirection */
        setfunc(m, &tr);
        errno = 0;
        if (varvalue(sa[0]) <= FTINY)
                return(0);              /* insignificant */
        if (errno)
                goto computerr;
        for (i = 0; i < 3; i++)
                newdir[i] = varvalue(sa[i+1]);
        if (errno)
                goto computerr;
        newdot = DOT(newdir, nv);
        if (newdot <= FTINY && newdot >= -FTINY)
                return(0);              /* new dir parallels plane */
                                /* everything OK -- compute shear */
        for (i = 0; i < 3; i++)
                h[i] = tr.rdir[i]/olddot + newdir[i]/newdot;
        setident4(pm);
        for (j = 0; j < 3; j++) {
                for (i = 0; i < 3; i++)
                        pm[i][j] += nv[i]*h[j];
                pm[3][j] = -od*h[j];
        }
        if (newdot > 0.0 ^ olddot > 0.0)        /* add mirroring */
                for (j = 0; j < 3; j++) {
                        for (i = 0; i < 3; i++)
                                pm[i][j] -= 2.*nv[i]*nv[j];
                        pm[3][j] += 2.*od*nv[j];
                }
        return(1);
computerr:
        objerror(m, WARNING, "projection compute error");
        return(0);
}


static
dir_check(m)                    /* check arguments and load function file */
register OBJREC  *m;
{
        register int  ff;

        ff = m->otype == MAT_DIRECT1 ? 4 : 8;
        if (ff >= m->oargs.nsargs)
                objerror(m, USER, "too few arguments");
        if (!vardefined(m->oargs.sarg[0]))
                loadfunc(m->oargs.sarg[ff]);
}
Revision:	1.3
Committed:	Tue Jul 16 17:16:32 1991 UTC (32 years, 9 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.2:	+18 -6 lines
Log Message:	added missing funcfile argument!
#	User	Rev	Content
1	greg	1.1	/* Copyright (c) 1991 Regents of the University of California */
2
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ LBL";
5			#endif
6
7			/*
8			* Routines for light-redirecting materials and
9			* their associated virtual light sources
10			*/
11
12			#include "ray.h"
13
14			#include "otypes.h"
15
16			#include "source.h"
17
18			/*
19			* The arguments for MAT_DIRECT1 are:
20			*
21	greg	1.3	* 5+ coef1 dx1 dy1 dz1 funcfile transform..
22	greg	1.1	* 0
23			* n A1 A2 .. An
24			*
25			* The arguments for MAT_DIRECT2 are:
26			*
27	greg	1.3	* 9+ coef1 dx1 dy1 dz1 coef2 dx2 dy2 dz2 funcfile transform..
28	greg	1.1	* 0
29			* n A1 A2 .. An
30			*/
31
32
33			extern double varvalue();
34
35			int dir_proj();
36			VSMATERIAL direct1_vs = {dir_proj, 1};
37			VSMATERIAL direct2_vs = {dir_proj, 2};
38
39
40			m_direct(m, r) /* shade redirected ray */
41			register OBJREC *m;
42			register RAY *r;
43			{
44			/* check if source ray */
45			if (r->rsrc >= 0 && source[r->rsrc].so != r->ro)
46			return; /* got the wrong guy */
47	greg	1.3	dir_check(m);
48	greg	1.1	/* compute first projection */
49			if (m->otype == MAT_DIRECT1 \|\|
50			(r->rsrc < 0 \|\| source[r->rsrc].sa.sv.pn == 0))
51			redirect(m, r, 0);
52			/* compute second projection */
53			if (m->otype == MAT_DIRECT2 &&
54			(r->rsrc < 0 \|\| source[r->rsrc].sa.sv.pn == 1))
55			redirect(m, r, 1);
56			}
57
58
59			redirect(m, r, n) /* compute n'th ray redirection */
60			OBJREC *m;
61			RAY *r;
62			int n;
63			{
64			register char **sa;
65			RAY nr;
66			double coef;
67			register int j;
68			/* set up function */
69			setfunc(m, r);
70			sa = m->oargs.sarg + 4*n;
71			/* compute coefficient */
72			errno = 0;
73			coef = varvalue(sa[0]);
74			if (errno)
75			goto computerr;
76			if (coef <= FTINY \|\| rayorigin(&nr, r, TRANS, coef) < 0)
77			return(0);
78			/* compute direction */
79			errno = 0;
80			for (j = 0; j < 3; j++)
81			nr.rdir[j] = varvalue(sa[j+1]);
82			if (errno \|\| normalize(nr.rdir) == 0.0)
83			goto computerr;
84			/* compute value */
85			if (r->rsrc >= 0)
86			nr.rsrc = source[r->rsrc].sa.sv.sn;
87			rayvalue(&nr);
88			scalecolor(nr.rcol, coef);
89			addcolor(r->rcol, nr.rcol);
90			return(1);
91			computerr:
92			objerror(m, WARNING, "compute error");
93			return(-1);
94			}
95
96
97			dir_proj(pm, o, s, n) /* compute a director's projection */
98			MAT4 pm;
99			OBJREC *o;
100			SRCREC *s;
101			int n;
102			{
103			RAY tr;
104			register OBJREC *m;
105			char **sa;
106			FVECT cent, newdir, nv, h;
107			double olddot, newdot, od;
108			register int i, j;
109			/* get material arguments */
110			m = objptr(o->omod);
111	greg	1.3	dir_check(m);
112	greg	1.1	sa = m->oargs.sarg + 4*n;
113			/* initialize test ray */
114			getmaxdisk(cent, o);
115			if (s->sflags & SDISTANT)
116			for (i = 0; i < 3; i++) {
117			tr.rdir[i] = -s->sloc[i];
118			tr.rorg[i] = cent[i] - tr.rdir[i];
119			}
120			else {
121			for (i = 0; i < 3; i++) {
122			tr.rdir[i] = cent[i] - s->sloc[i];
123	greg	1.2	tr.rorg[i] = s->sloc[i];
124	greg	1.1	}
125			if (normalize(tr.rdir) == 0.0)
126			return(0); /* at source! */
127			}
128			od = getplaneq(nv, o);
129			olddot = DOT(tr.rdir, nv);
130			if (olddot <= FTINY && olddot >= -FTINY)
131			return(0); /* old dir parallels plane */
132			rayorigin(&tr, NULL, PRIMARY, 1.0);
133			if (!(*ofun[o->otype].funp)(o, &tr))
134			return(0); /* no intersection! */
135			/* compute redirection */
136			setfunc(m, &tr);
137			errno = 0;
138			if (varvalue(sa[0]) <= FTINY)
139			return(0); /* insignificant */
140			if (errno)
141			goto computerr;
142			for (i = 0; i < 3; i++)
143			newdir[i] = varvalue(sa[i+1]);
144			if (errno)
145			goto computerr;
146			newdot = DOT(newdir, nv);
147			if (newdot <= FTINY && newdot >= -FTINY)
148			return(0); /* new dir parallels plane */
149			/* everything OK -- compute shear */
150			for (i = 0; i < 3; i++)
151			h[i] = tr.rdir[i]/olddot + newdir[i]/newdot;
152			setident4(pm);
153			for (j = 0; j < 3; j++) {
154			for (i = 0; i < 3; i++)
155			pm[i][j] += nv[i]*h[j];
156			pm[3][j] = -od*h[j];
157			}
158			if (newdot > 0.0 ^ olddot > 0.0) /* add mirroring */
159			for (j = 0; j < 3; j++) {
160			for (i = 0; i < 3; i++)
161			pm[i][j] -= 2.nv[i]nv[j];
162			pm[3][j] += 2.odnv[j];
163			}
164			return(1);
165			computerr:
166			objerror(m, WARNING, "projection compute error");
167			return(0);
168	greg	1.3	}
169
170
171			static
172			dir_check(m) /* check arguments and load function file */
173			register OBJREC *m;
174			{
175			register int ff;
176
177			ff = m->otype == MAT_DIRECT1 ? 4 : 8;
178			if (ff >= m->oargs.nsargs)
179			objerror(m, USER, "too few arguments");
180			if (!vardefined(m->oargs.sarg[0]))
181			loadfunc(m->oargs.sarg[ff]);
182	greg	1.1	}