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"

#include  "func.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
 */


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

#define getdfunc(m)     ( (m)->otype == MAT_DIRECT1 ? \
                                getfunc(m, 4, 0xf, 1) : \
                                getfunc(m, 8, 0xff, 1) )


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 */
                                        /* 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;
{
        MFUNC  *mf;
        register EPNODE  **va;
        RAY  nr;
        double  coef;
        register int  j;
                                        /* set up function */
        mf = getdfunc(m);
        setfunc(m, r);
                                        /* compute coefficient */
        errno = 0;
        va = mf->ep + 4*n;
        coef = evalue(va[0]);
        if (errno)
                goto computerr;
        if (coef <= FTINY || rayorigin(&nr, r, TRANS, coef) < 0)
                return(0);
        va++;                           /* compute direction */
        for (j = 0; j < 3; j++) {
                nr.rdir[j] = evalue(va[j]);
                if (errno)
                        goto computerr;
        }
        if (mf->f != &unitxf)
                multv3(nr.rdir, nr.rdir, mf->f->xfm);
        if (r->rox != NULL)
                multv3(nr.rdir, nr.rdir, r->rox->f.xfm);
        if (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;
        OBJREC  *m;
        MFUNC  *mf;
        EPNODE  **va;
        FVECT  cent, newdir, nv, h;
        double  coef, olddot, newdot, od;
        register int  i, j;
                                /* 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 */
        m = vsmaterial(o);
        mf = getdfunc(m);
        setfunc(m, &tr);
        errno = 0;
        va = mf->ep + 4*n;
        coef = evalue(va[0]);
        if (errno)
                goto computerr;
        if (coef <= FTINY)
                return(0);              /* insignificant */
        va++;
        for (i = 0; i < 3; i++) {
                newdir[i] = evalue(va[i]);
                if (errno)
                        goto computerr;
        }
        if (mf->f != &unitxf)
                multv3(newdir, newdir, mf->f->xfm);
                                        /* normalization unnecessary */
        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] = newdir[i]/newdot - tr.rdir[i]/olddot;
        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);
}
Revision:	2.2
Committed:	Mon Nov 25 09:51:06 1991 UTC (32 years, 5 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.1:	+38 -58 lines
Log Message:	changed function file calls to allow expressions instead of just vars
#	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	greg	2.2	#include "func.h"
19
20	greg	1.1	/*
21			* The arguments for MAT_DIRECT1 are:
22			*
23	greg	1.3	* 5+ coef1 dx1 dy1 dz1 funcfile transform..
24	greg	1.1	* 0
25			* n A1 A2 .. An
26			*
27			* The arguments for MAT_DIRECT2 are:
28			*
29	greg	1.3	* 9+ coef1 dx1 dy1 dz1 coef2 dx2 dy2 dz2 funcfile transform..
30	greg	1.1	* 0
31			* n A1 A2 .. An
32			*/
33
34
35			int dir_proj();
36			VSMATERIAL direct1_vs = {dir_proj, 1};
37			VSMATERIAL direct2_vs = {dir_proj, 2};
38
39	greg	2.2	#define getdfunc(m) ( (m)->otype == MAT_DIRECT1 ? \
40			getfunc(m, 4, 0xf, 1) : \
41			getfunc(m, 8, 0xff, 1) )
42	greg	1.1
43	greg	1.6
44	greg	1.1	m_direct(m, r) /* shade redirected ray */
45			register OBJREC *m;
46			register RAY *r;
47			{
48			/* check if source ray */
49			if (r->rsrc >= 0 && source[r->rsrc].so != r->ro)
50			return; /* got the wrong guy */
51			/* compute first projection */
52			if (m->otype == MAT_DIRECT1 \|\|
53			(r->rsrc < 0 \|\| source[r->rsrc].sa.sv.pn == 0))
54			redirect(m, r, 0);
55			/* compute second projection */
56			if (m->otype == MAT_DIRECT2 &&
57			(r->rsrc < 0 \|\| source[r->rsrc].sa.sv.pn == 1))
58			redirect(m, r, 1);
59			}
60
61
62			redirect(m, r, n) /* compute n'th ray redirection */
63			OBJREC *m;
64			RAY *r;
65			int n;
66			{
67	greg	2.2	MFUNC *mf;
68			register EPNODE **va;
69	greg	1.1	RAY nr;
70			double coef;
71			register int j;
72			/* set up function */
73	greg	2.2	mf = getdfunc(m);
74			setfunc(m, r);
75	greg	1.1	/* compute coefficient */
76			errno = 0;
77	greg	2.2	va = mf->ep + 4*n;
78			coef = evalue(va[0]);
79	greg	1.1	if (errno)
80			goto computerr;
81			if (coef <= FTINY \|\| rayorigin(&nr, r, TRANS, coef) < 0)
82			return(0);
83	greg	2.2	va++; /* compute direction */
84			for (j = 0; j < 3; j++) {
85			nr.rdir[j] = evalue(va[j]);
86			if (errno)
87			goto computerr;
88			}
89			if (mf->f != &unitxf)
90			multv3(nr.rdir, nr.rdir, mf->f->xfm);
91	greg	1.4	if (r->rox != NULL)
92			multv3(nr.rdir, nr.rdir, r->rox->f.xfm);
93			if (normalize(nr.rdir) == 0.0)
94			goto computerr;
95	greg	1.1	/* compute value */
96			if (r->rsrc >= 0)
97			nr.rsrc = source[r->rsrc].sa.sv.sn;
98			rayvalue(&nr);
99			scalecolor(nr.rcol, coef);
100			addcolor(r->rcol, nr.rcol);
101			return(1);
102			computerr:
103			objerror(m, WARNING, "compute error");
104			return(-1);
105			}
106
107
108			dir_proj(pm, o, s, n) /* compute a director's projection */
109			MAT4 pm;
110			OBJREC *o;
111			SRCREC *s;
112			int n;
113			{
114			RAY tr;
115	greg	2.2	OBJREC *m;
116			MFUNC *mf;
117			EPNODE **va;
118	greg	1.1	FVECT cent, newdir, nv, h;
119	greg	2.2	double coef, olddot, newdot, od;
120	greg	1.1	register int i, j;
121			/* initialize test ray */
122			getmaxdisk(cent, o);
123			if (s->sflags & SDISTANT)
124			for (i = 0; i < 3; i++) {
125			tr.rdir[i] = -s->sloc[i];
126			tr.rorg[i] = cent[i] - tr.rdir[i];
127			}
128			else {
129			for (i = 0; i < 3; i++) {
130			tr.rdir[i] = cent[i] - s->sloc[i];
131	greg	1.2	tr.rorg[i] = s->sloc[i];
132	greg	1.1	}
133			if (normalize(tr.rdir) == 0.0)
134			return(0); /* at source! */
135			}
136			od = getplaneq(nv, o);
137			olddot = DOT(tr.rdir, nv);
138			if (olddot <= FTINY && olddot >= -FTINY)
139			return(0); /* old dir parallels plane */
140			rayorigin(&tr, NULL, PRIMARY, 1.0);
141			if (!(*ofun[o->otype].funp)(o, &tr))
142			return(0); /* no intersection! */
143			/* compute redirection */
144	greg	2.2	m = vsmaterial(o);
145			mf = getdfunc(m);
146			setfunc(m, &tr);
147	greg	1.1	errno = 0;
148	greg	2.2	va = mf->ep + 4*n;
149			coef = evalue(va[0]);
150	greg	1.1	if (errno)
151			goto computerr;
152	greg	2.2	if (coef <= FTINY)
153			return(0); /* insignificant */
154			va++;
155			for (i = 0; i < 3; i++) {
156			newdir[i] = evalue(va[i]);
157			if (errno)
158			goto computerr;
159			}
160			if (mf->f != &unitxf)
161			multv3(newdir, newdir, mf->f->xfm);
162	greg	1.4	/* normalization unnecessary */
163	greg	1.1	newdot = DOT(newdir, nv);
164			if (newdot <= FTINY && newdot >= -FTINY)
165			return(0); /* new dir parallels plane */
166			/* everything OK -- compute shear */
167			for (i = 0; i < 3; i++)
168	greg	1.4	h[i] = newdir[i]/newdot - tr.rdir[i]/olddot;
169	greg	1.1	setident4(pm);
170			for (j = 0; j < 3; j++) {
171			for (i = 0; i < 3; i++)
172			pm[i][j] += nv[i]*h[j];
173			pm[3][j] = -od*h[j];
174			}
175			if (newdot > 0.0 ^ olddot > 0.0) /* add mirroring */
176			for (j = 0; j < 3; j++) {
177			for (i = 0; i < 3; i++)
178			pm[i][j] -= 2.nv[i]nv[j];
179			pm[3][j] += 2.odnv[j];
180			}
181			return(1);
182			computerr:
183			objerror(m, WARNING, "projection compute error");
184			return(0);
185			}