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};

#define fndx(m)         ((m)->otype == MAT_DIRECT1 ? 4 : 8)


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

        ff = fndx(m)+1;
        if (ff > m->oargs.nsargs)
                objerror(m, USER, "too few arguments");
        if (m->os == NULL) {
                mxf = (FULLXF *)malloc(sizeof(FULLXF));
                if (mxf == NULL)
                        error(SYSTEM, "out of memory in dir_check");
                if (fullxf(mxf, m->oargs.nsargs-ff, m->oargs.sarg+ff) !=
                                m->oargs.nsargs-ff)
                        objerror(m, USER, "bad transform");
                if (mxf->f.sca < 0.0)
                        mxf->f.sca = -mxf->f.sca;
                if (mxf->b.sca < 0.0)
                        mxf->b.sca = -mxf->b.sca;
                m->os = (char *)mxf;
        }
}


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 */
        setmap(m, r, &((FULLXF *)m->os)->b);
        funcfile(m->oargs.sarg[fndx(m)]);
        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)
                goto computerr;
        multv3(nr.rdir, nr.rdir, ((FULLXF *)m->os)->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;
        register OBJREC  *m;
        char  **sa;
        FVECT  cent, newdir, nv, h;
        double  olddot, newdot, od;
        register int  i, j;
                                /* get material arguments */
        m = vsmaterial(o);
        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 */
        setmap(m, &tr, &((FULLXF *)m->os)->b);
        funcfile(m->oargs.sarg[fndx(m)]);
        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;
        multv3(newdir, newdir, ((FULLXF *)m->os)->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:	2.1
Committed:	Tue Nov 12 17:10:36 1991 UTC (33 years, 11 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.7:	+0 -0 lines
Log Message:	updated revision number for release 2.0
#	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	greg	1.6	#define fndx(m) ((m)->otype == MAT_DIRECT1 ? 4 : 8)
40	greg	1.1
41	greg	1.6
42			static
43			dir_check(m) /* check arguments and load function file */
44			register OBJREC *m;
45			{
46			register FULLXF *mxf;
47			register int ff;
48
49			ff = fndx(m)+1;
50			if (ff > m->oargs.nsargs)
51			objerror(m, USER, "too few arguments");
52			if (m->os == NULL) {
53			mxf = (FULLXF *)malloc(sizeof(FULLXF));
54			if (mxf == NULL)
55			error(SYSTEM, "out of memory in dir_check");
56			if (fullxf(mxf, m->oargs.nsargs-ff, m->oargs.sarg+ff) !=
57			m->oargs.nsargs-ff)
58			objerror(m, USER, "bad transform");
59			if (mxf->f.sca < 0.0)
60			mxf->f.sca = -mxf->f.sca;
61			if (mxf->b.sca < 0.0)
62			mxf->b.sca = -mxf->b.sca;
63			m->os = (char *)mxf;
64			}
65			}
66
67
68	greg	1.1	m_direct(m, r) /* shade redirected ray */
69			register OBJREC *m;
70			register RAY *r;
71			{
72			/* check if source ray */
73			if (r->rsrc >= 0 && source[r->rsrc].so != r->ro)
74			return; /* got the wrong guy */
75	greg	1.3	dir_check(m);
76	greg	1.1	/* compute first projection */
77			if (m->otype == MAT_DIRECT1 \|\|
78			(r->rsrc < 0 \|\| source[r->rsrc].sa.sv.pn == 0))
79			redirect(m, r, 0);
80			/* compute second projection */
81			if (m->otype == MAT_DIRECT2 &&
82			(r->rsrc < 0 \|\| source[r->rsrc].sa.sv.pn == 1))
83			redirect(m, r, 1);
84			}
85
86
87			redirect(m, r, n) /* compute n'th ray redirection */
88			OBJREC *m;
89			RAY *r;
90			int n;
91			{
92			register char **sa;
93			RAY nr;
94			double coef;
95			register int j;
96			/* set up function */
97	greg	1.4	setmap(m, r, &((FULLXF *)m->os)->b);
98	greg	1.6	funcfile(m->oargs.sarg[fndx(m)]);
99	greg	1.1	sa = m->oargs.sarg + 4*n;
100			/* compute coefficient */
101			errno = 0;
102			coef = varvalue(sa[0]);
103			if (errno)
104			goto computerr;
105			if (coef <= FTINY \|\| rayorigin(&nr, r, TRANS, coef) < 0)
106			return(0);
107			/* compute direction */
108			errno = 0;
109			for (j = 0; j < 3; j++)
110			nr.rdir[j] = varvalue(sa[j+1]);
111	greg	1.4	if (errno)
112	greg	1.1	goto computerr;
113	greg	1.4	multv3(nr.rdir, nr.rdir, ((FULLXF *)m->os)->f.xfm);
114			if (r->rox != NULL)
115			multv3(nr.rdir, nr.rdir, r->rox->f.xfm);
116			if (normalize(nr.rdir) == 0.0)
117			goto computerr;
118	greg	1.1	/* compute value */
119			if (r->rsrc >= 0)
120			nr.rsrc = source[r->rsrc].sa.sv.sn;
121			rayvalue(&nr);
122			scalecolor(nr.rcol, coef);
123			addcolor(r->rcol, nr.rcol);
124			return(1);
125			computerr:
126			objerror(m, WARNING, "compute error");
127			return(-1);
128			}
129
130
131			dir_proj(pm, o, s, n) /* compute a director's projection */
132			MAT4 pm;
133			OBJREC *o;
134			SRCREC *s;
135			int n;
136			{
137			RAY tr;
138			register OBJREC *m;
139			char **sa;
140			FVECT cent, newdir, nv, h;
141			double olddot, newdot, od;
142			register int i, j;
143			/* get material arguments */
144	greg	1.7	m = vsmaterial(o);
145	greg	1.3	dir_check(m);
146	greg	1.1	sa = m->oargs.sarg + 4*n;
147			/* initialize test ray */
148			getmaxdisk(cent, o);
149			if (s->sflags & SDISTANT)
150			for (i = 0; i < 3; i++) {
151			tr.rdir[i] = -s->sloc[i];
152			tr.rorg[i] = cent[i] - tr.rdir[i];
153			}
154			else {
155			for (i = 0; i < 3; i++) {
156			tr.rdir[i] = cent[i] - s->sloc[i];
157	greg	1.2	tr.rorg[i] = s->sloc[i];
158	greg	1.1	}
159			if (normalize(tr.rdir) == 0.0)
160			return(0); /* at source! */
161			}
162			od = getplaneq(nv, o);
163			olddot = DOT(tr.rdir, nv);
164			if (olddot <= FTINY && olddot >= -FTINY)
165			return(0); /* old dir parallels plane */
166			rayorigin(&tr, NULL, PRIMARY, 1.0);
167			if (!(*ofun[o->otype].funp)(o, &tr))
168			return(0); /* no intersection! */
169			/* compute redirection */
170	greg	1.4	setmap(m, &tr, &((FULLXF *)m->os)->b);
171	greg	1.6	funcfile(m->oargs.sarg[fndx(m)]);
172	greg	1.1	errno = 0;
173			if (varvalue(sa[0]) <= FTINY)
174			return(0); /* insignificant */
175			if (errno)
176			goto computerr;
177			for (i = 0; i < 3; i++)
178			newdir[i] = varvalue(sa[i+1]);
179			if (errno)
180			goto computerr;
181	greg	1.4	multv3(newdir, newdir, ((FULLXF *)m->os)->f.xfm);
182			/* normalization unnecessary */
183	greg	1.1	newdot = DOT(newdir, nv);
184			if (newdot <= FTINY && newdot >= -FTINY)
185			return(0); /* new dir parallels plane */
186			/* everything OK -- compute shear */
187			for (i = 0; i < 3; i++)
188	greg	1.4	h[i] = newdir[i]/newdot - tr.rdir[i]/olddot;
189	greg	1.1	setident4(pm);
190			for (j = 0; j < 3; j++) {
191			for (i = 0; i < 3; i++)
192			pm[i][j] += nv[i]*h[j];
193			pm[3][j] = -od*h[j];
194			}
195			if (newdot > 0.0 ^ olddot > 0.0) /* add mirroring */
196			for (j = 0; j < 3; j++) {
197			for (i = 0; i < 3; i++)
198			pm[i][j] -= 2.nv[i]nv[j];
199			pm[3][j] += 2.odnv[j];
200			}
201			return(1);
202			computerr:
203			objerror(m, WARNING, "projection compute error");
204			return(0);
205			}