src/gen/mkillum2.c

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

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

/*
 * Routines to do the actual calculation for mkillum
 */

#include  "mkillum.h"

#include  "face.h"

#include  "cone.h"

#include  "random.h"


o_default(ob, il, rt, nm)       /* default illum action */
OBJREC  *ob;
struct illum_args  *il;
struct rtproc  *rt;
char  *nm;
{
        sprintf(errmsg, "(%s): cannot make illum for %s \"%s\"",
                        nm, ofun[ob->otype].funame, ob->oname);
        error(WARNING, errmsg);
        if (!(il->flags & IL_LIGHT))
                printobj(il->altmat, ob);
}


o_face(ob, il, rt, nm)          /* make an illum face */
OBJREC  *ob;
struct illum_args  *il;
struct rtproc  *rt;
char  *nm;
{
#define MAXMISS         (5*n*il->nsamps)
        int  dim[4];
        int  n, nalt, nazi;
        float  *distarr;
        double  r1, r2;
        FVECT  dn, org, dir;
        FVECT  u, v;
        double  ur[2], vr[2];
        int  nmisses;
        register FACE  *fa;
        register int  i, j;
                                /* get/check arguments */
        fa = getface(ob);
        if (fa->area == 0.0) {
                freeface(ob);
                o_default(ob, il, rt, nm);
                return;
        }
                                /* set up sampling */
        n = PI * il->sampdens;
        nalt = sqrt(n/PI) + .5;
        nazi = PI*nalt + .5;
        n = nalt*nazi;
        distarr = (float *)calloc(n, 3*sizeof(float));
        if (distarr == NULL)
                error(SYSTEM, "out of memory in o_face");
        mkaxes(u, v, fa->norm);
        ur[0] = vr[0] = FHUGE;
        ur[1] = vr[1] = -FHUGE;
        for (i = 0; i < fa->nv; i++) {
                r1 = DOT(VERTEX(fa,i),u);
                if (r1 < ur[0]) ur[0] = r1;
                if (r1 > ur[1]) ur[1] = r1;
                r2 = DOT(VERTEX(fa,i),v);
                if (r2 < vr[0]) vr[0] = r2;
                if (r2 > vr[1]) vr[1] = r2;
        }
        dim[0] = random();
                                /* sample polygon */
        nmisses = 0;
        for (dim[1] = 0; dim[1] < nalt; dim[1]++)
            for (dim[2] = 0; dim[2] < nazi; dim[2]++)
                for (i = 0; i < il->nsamps; i++) {
                                        /* random direction */
                    dim[3] = 1;
                    r1 = (dim[1]+urand(urind(ilhash(dim,4),i)))/nalt;
                    dim[3] = 2;
                    r2 = (dim[2]+urand(urind(ilhash(dim,4),i)))/nalt;
                    flatdir(dn, r1, r2);
                    for (j = 0; j < 3; j++)
                        dir[j] = dn[0]*u[j] + dn[1]*v[j] - dn[2]*fa->norm[j];
                                        /* random location */
                    do {
                        dim[3] = 3;
                        r1 = ur[0] + (ur[1]-ur[0]) *
                                        urand(urind(ilhash(dim,4),i+nmisses));
                        dim[3] = 4;
                        r2 = vr[0] + (vr[1]-vr[0]) *
                                        urand(urind(ilhash(dim,4),i+nmisses));
                        for (j = 0; j < 3; j++)
                            org[j] = r1*u[j] + r2*v[j]
                                        + fa->offset*fa->norm[j];
                    } while (!inface(org, fa) && nmisses++ < MAXMISS);
                    if (nmisses > MAXMISS) {
                        objerror(ob, WARNING, "bad aspect");
                        rt->nrays = 0;
                        freeface(ob);
                        free((char *)distarr);
                        o_default(ob, il, rt, nm);
                        return;
                    }
                    for (j = 0; j < 3; j++)
                        org[j] += .001*fa->norm[j];
                                        /* send sample */
                    raysamp(distarr+dim[1]*nazi+dim[2], org, dir, rt);
                }
        rayflush(rt);
                                /* write out the face w/ distribution */
        flatout(il, distarr, nalt, nazi, u, v, fa->norm);
        illumout(il, ob);
                                /* clean up */
        freeface(ob);
        free((char *)distarr);
#undef MAXMISS
}


o_sphere(ob, il, rt, nm)        /* make an illum sphere */
register OBJREC  *ob;
struct illum_args  *il;
struct rtproc  *rt;
char  *nm;
{
        int  dim[4];
        int  n, nalt, nazi;
        float  *distarr;
        double  r1, r2;
        FVECT  org, dir;
        FVECT  u, v;
        register int  i, j;
                                /* check arguments */
        if (ob->oargs.nfargs != 4)
                objerror(ob, USER, "bad # of arguments");
                                /* set up sampling */
        n = 4.*PI * il->sampdens;
        nalt = sqrt(n/PI) + .5;
        nazi = PI*nalt + .5;
        n = nalt*nazi;
        distarr = (float *)calloc(n, 3*sizeof(float));
        if (distarr == NULL)
                error(SYSTEM, "out of memory in o_sphere");
        dim[0] = random();
                                /* sample sphere */
        for (dim[1] = 0; dim[1] < nalt; dim[1]++)
            for (dim[2] = 0; dim[2] < nazi; dim[2]++)
                for (i = 0; i < il->nsamps; i++) {
                                        /* random direction */
                    dim[3] = 1;
                    r1 = (dim[1]+urand(urind(ilhash(dim,4),i)))/nalt;
                    dim[3] = 2;
                    r2 = (dim[2]+urand(urind(ilhash(dim,4),i)))/nalt;
                    rounddir(dir, r1, r2);
                                        /* random location */
                    mkaxes(u, v, dir);          /* yuck! */
                    dim[3] = 3;
                    r1 = sqrt(urand(urind(ilhash(dim,4),i)));
                    dim[3] = 4;
                    r2 = 2.*PI*urand(urind(ilhash(dim,4),i));
                    for (j = 0; j < 3; j++)
                        org[j] = ob->oargs.farg[j] + ob->oargs.farg[3] *
                                        ( r1*cos(r2)*u[j] + r1*sin(r2)*v[j]
                                                - sqrt(1.01-r1*r1)*dir[j] );

                                        /* send sample */
                    raysamp(distarr+dim[1]*nazi+dim[2], org, dir, rt);
                }
        rayflush(rt);
                                /* write out the sphere w/ distribution */
        roundout(il, distarr, nalt, nazi);
        illumout(il, ob);
                                /* clean up */
        free((char *)distarr);
}


o_ring(ob, il, rt, nm)          /* make an illum ring */
OBJREC  *ob;
struct illum_args  *il;
struct rtproc  *rt;
char  *nm;
{
        int  dim[4];
        int  n, nalt, nazi;
        float  *distarr;
        double  r1, r2;
        FVECT  dn, org, dir;
        FVECT  u, v;
        register CONE  *co;
        register int  i, j;
                                /* get/check arguments */
        co = getcone(ob, 0);
                                /* set up sampling */
        n = PI * il->sampdens;
        nalt = sqrt(n/PI) + .5;
        nazi = PI*nalt + .5;
        n = nalt*nazi;
        distarr = (float *)calloc(n, 3*sizeof(float));
        if (distarr == NULL)
                error(SYSTEM, "out of memory in o_ring");
        mkaxes(u, v, co->ad);
        dim[0] = random();
                                /* sample disk */
        for (dim[1] = 0; dim[1] < nalt; dim[1]++)
            for (dim[2] = 0; dim[2] < nazi; dim[2]++)
                for (i = 0; i < il->nsamps; i++) {
                                        /* random direction */
                    dim[3] = 1;
                    r1 = (dim[1]+urand(urind(ilhash(dim,4),i)))/nalt;
                    dim[3] = 2;
                    r2 = (dim[2]+urand(urind(ilhash(dim,4),i)))/nalt;
                    flatdir(dn, r1, r2);
                    for (j = 0; j < 3; j++)
                        dir[j] = dn[0]*u[j] + dn[1]*v[j] - dn[2]*co->ad[j];
                                        /* random location */
                    dim[3] = 3;
                    r1 = sqrt(CO_R0(co)*CO_R0(co) +
                                urand(urind(ilhash(dim,4),i))*
                                (CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co)));
                    dim[3] = 4;
                    r2 = 2.*PI*urand(urind(ilhash(dim,4),i));
                    for (j = 0; j < 3; j++)
                        org[j] = CO_P0(co)[j] +
                                        r1*cos(r2)*u[j] + r1*sin(r2)*v[j]
                                        + .001*co->ad[j];

                                        /* send sample */
                    raysamp(distarr+dim[1]*nazi+dim[2], org, dir, rt);
                }
        rayflush(rt);
                                /* write out the ring w/ distribution */
        flatout(il, distarr, nalt, nazi, u, v, co->ad);
        illumout(il, ob);
                                /* clean up */
        freecone(ob);
        free((char *)distarr);
}


raysamp(res, org, dir, rt)      /* compute a ray sample */
float  res[3];
FVECT  org, dir;
register struct rtproc  *rt;
{
        register float  *fp;

        if (rt->nrays == rt->bsiz)
                rayflush(rt);
        rt->dest[rt->nrays] = res;
        fp = rt->buf + 6*rt->nrays++;
        *fp++ = org[0]; *fp++ = org[1]; *fp++ = org[2];
        *fp++ = dir[0]; *fp++ = dir[1]; *fp = dir[2];
}


rayflush(rt)                    /* flush buffered rays */
register struct rtproc  *rt;
{
        register int  i;

        if (rt->nrays <= 0)
                return;
        i = 6*rt->nrays + 3;
        rt->buf[i++] = 0.; rt->buf[i++] = 0.; rt->buf[i] = 0.;
        if ( process(rt->pd, (char *)rt->buf, (char *)rt->buf,
                        3*sizeof(float)*rt->nrays,
                        6*sizeof(float)*(rt->nrays+1)) <
                        3*sizeof(float)*rt->nrays )
                error(SYSTEM, "error reading from rtrace process");
        i = rt->nrays;
        while (i--) {
                rt->dest[i][0] += rt->buf[3*i];
                rt->dest[i][1] += rt->buf[3*i+1];
                rt->dest[i][2] += rt->buf[3*i+2];
        }
        rt->nrays = 0;
}


mkaxes(u, v, n)                 /* compute u and v to go with n */
FVECT  u, v, n;
{
        register int  i;

        v[0] = v[1] = v[2] = 0.0;
        for (i = 0; i < 3; i++)
                if (n[i] < 0.6 && n[i] > -0.6)
                        break;
        v[i] = 1.0;
        fcross(u, v, n);
        normalize(u);
        fcross(v, n, u);
}


rounddir(dv, alt, azi)          /* compute uniform spherical direction */
register FVECT  dv;
double  alt, azi;
{
        double  d1, d2;

        dv[2] = 1. - 2.*alt;
        d1 = sqrt(1. - dv[2]*dv[2]);
        d2 = 2.*PI * azi;
        dv[0] = d1*cos(d2);
        dv[1] = d1*sin(d2);
}


flatdir(dv, alt, azi)           /* compute uniform hemispherical direction */
register FVECT  dv;
double  alt, azi;
{
        double  d1, d2;

        d1 = sqrt(alt);
        d2 = 2.*PI * azi;
        dv[0] = d1*cos(d2);
        dv[1] = d1*sin(d2);
        dv[2] = sqrt(1. - d1*d1);
}
Revision:	1.4
Committed:	Wed Jul 24 16:48:26 1991 UTC (32 years, 9 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.3:	+63 -43 lines
Log Message:	first version of mkillum
#	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	greg	1.4	* Routines to do the actual calculation for mkillum
9	greg	1.1	*/
10
11			#include "mkillum.h"
12
13			#include "face.h"
14
15			#include "cone.h"
16
17	greg	1.2	#include "random.h"
18	greg	1.1
19	greg	1.2
20			o_default(ob, il, rt, nm) /* default illum action */
21	greg	1.1	OBJREC *ob;
22			struct illum_args *il;
23			struct rtproc *rt;
24	greg	1.2	char *nm;
25	greg	1.1	{
26	greg	1.2	sprintf(errmsg, "(%s): cannot make illum for %s \"%s\"",
27			nm, ofun[ob->otype].funame, ob->oname);
28			error(WARNING, errmsg);
29			if (!(il->flags & IL_LIGHT))
30	greg	1.4	printobj(il->altmat, ob);
31	greg	1.2	}
32
33
34			o_face(ob, il, rt, nm) /* make an illum face */
35			OBJREC *ob;
36			struct illum_args *il;
37			struct rtproc *rt;
38			char *nm;
39			{
40	greg	1.3	#define MAXMISS (5nil->nsamps)
41			int dim[4];
42			int n, nalt, nazi;
43			float *distarr;
44			double r1, r2;
45	greg	1.4	FVECT dn, org, dir;
46	greg	1.3	FVECT u, v;
47			double ur[2], vr[2];
48			int nmisses;
49			register FACE *fa;
50			register int i, j;
51			/* get/check arguments */
52			fa = getface(ob);
53			if (fa->area == 0.0) {
54			freeface(ob);
55			o_default(ob, il, rt, nm);
56			return;
57			}
58			/* set up sampling */
59			n = PI * il->sampdens;
60			nalt = sqrt(n/PI) + .5;
61			nazi = PI*nalt + .5;
62			n = nalt*nazi;
63			distarr = (float )calloc(n, 3sizeof(float));
64			if (distarr == NULL)
65			error(SYSTEM, "out of memory in o_face");
66			mkaxes(u, v, fa->norm);
67			ur[0] = vr[0] = FHUGE;
68			ur[1] = vr[1] = -FHUGE;
69			for (i = 0; i < fa->nv; i++) {
70			r1 = DOT(VERTEX(fa,i),u);
71			if (r1 < ur[0]) ur[0] = r1;
72			if (r1 > ur[1]) ur[1] = r1;
73			r2 = DOT(VERTEX(fa,i),v);
74			if (r2 < vr[0]) vr[0] = r2;
75			if (r2 > vr[1]) vr[1] = r2;
76			}
77			dim[0] = random();
78			/* sample polygon */
79			nmisses = 0;
80			for (dim[1] = 0; dim[1] < nalt; dim[1]++)
81			for (dim[2] = 0; dim[2] < nazi; dim[2]++)
82			for (i = 0; i < il->nsamps; i++) {
83			/* random direction */
84			dim[3] = 1;
85			r1 = (dim[1]+urand(urind(ilhash(dim,4),i)))/nalt;
86			dim[3] = 2;
87			r2 = (dim[2]+urand(urind(ilhash(dim,4),i)))/nalt;
88			flatdir(dn, r1, r2);
89			for (j = 0; j < 3; j++)
90			dir[j] = dn[0]u[j] + dn[1]v[j] - dn[2]*fa->norm[j];
91			/* random location */
92			do {
93			dim[3] = 3;
94	greg	1.4	r1 = ur[0] + (ur[1]-ur[0]) *
95			urand(urind(ilhash(dim,4),i+nmisses));
96	greg	1.3	dim[3] = 4;
97	greg	1.4	r2 = vr[0] + (vr[1]-vr[0]) *
98			urand(urind(ilhash(dim,4),i+nmisses));
99	greg	1.3	for (j = 0; j < 3; j++)
100			org[j] = r1u[j] + r2v[j]
101			+ fa->offset*fa->norm[j];
102			} while (!inface(org, fa) && nmisses++ < MAXMISS);
103			if (nmisses > MAXMISS) {
104			objerror(ob, WARNING, "bad aspect");
105			rt->nrays = 0;
106			freeface(ob);
107			free((char *)distarr);
108			o_default(ob, il, rt, nm);
109			return;
110			}
111			for (j = 0; j < 3; j++)
112			org[j] += .001*fa->norm[j];
113			/* send sample */
114			raysamp(distarr+dim[1]*nazi+dim[2], org, dir, rt);
115			}
116			rayflush(rt);
117	greg	1.4	/* write out the face w/ distribution */
118			flatout(il, distarr, nalt, nazi, u, v, fa->norm);
119			illumout(il, ob);
120	greg	1.3	/* clean up */
121			freeface(ob);
122			free((char *)distarr);
123			#undef MAXMISS
124	greg	1.2	}
125
126
127			o_sphere(ob, il, rt, nm) /* make an illum sphere */
128	greg	1.3	register OBJREC *ob;
129	greg	1.2	struct illum_args *il;
130			struct rtproc *rt;
131			char *nm;
132			{
133			int dim[4];
134			int n, nalt, nazi;
135			float *distarr;
136			double r1, r2;
137	greg	1.4	FVECT org, dir;
138	greg	1.2	FVECT u, v;
139			register int i, j;
140			/* check arguments */
141			if (ob->oargs.nfargs != 4)
142			objerror(ob, USER, "bad # of arguments");
143			/* set up sampling */
144			n = 4.PI il->sampdens;
145			nalt = sqrt(n/PI) + .5;
146			nazi = PI*nalt + .5;
147			n = nalt*nazi;
148			distarr = (float )calloc(n, 3sizeof(float));
149			if (distarr == NULL)
150			error(SYSTEM, "out of memory in o_sphere");
151			dim[0] = random();
152			/* sample sphere */
153			for (dim[1] = 0; dim[1] < nalt; dim[1]++)
154			for (dim[2] = 0; dim[2] < nazi; dim[2]++)
155			for (i = 0; i < il->nsamps; i++) {
156			/* random direction */
157			dim[3] = 1;
158			r1 = (dim[1]+urand(urind(ilhash(dim,4),i)))/nalt;
159			dim[3] = 2;
160			r2 = (dim[2]+urand(urind(ilhash(dim,4),i)))/nalt;
161			rounddir(dir, r1, r2);
162			/* random location */
163			mkaxes(u, v, dir); /* yuck! */
164			dim[3] = 3;
165			r1 = sqrt(urand(urind(ilhash(dim,4),i)));
166			dim[3] = 4;
167			r2 = 2.PIurand(urind(ilhash(dim,4),i));
168			for (j = 0; j < 3; j++)
169	greg	1.4	org[j] = ob->oargs.farg[j] + ob->oargs.farg[3] *
170	greg	1.2	( r1cos(r2)u[j] + r1sin(r2)v[j]
171			- sqrt(1.01-r1r1)dir[j] );
172
173			/* send sample */
174			raysamp(distarr+dim[1]*nazi+dim[2], org, dir, rt);
175			}
176			rayflush(rt);
177	greg	1.4	/* write out the sphere w/ distribution */
178			roundout(il, distarr, nalt, nazi);
179			illumout(il, ob);
180	greg	1.2	/* clean up */
181			free((char *)distarr);
182			}
183
184
185			o_ring(ob, il, rt, nm) /* make an illum ring */
186			OBJREC *ob;
187			struct illum_args *il;
188			struct rtproc *rt;
189			char *nm;
190			{
191	greg	1.3	int dim[4];
192			int n, nalt, nazi;
193			float *distarr;
194			double r1, r2;
195	greg	1.4	FVECT dn, org, dir;
196	greg	1.3	FVECT u, v;
197			register CONE *co;
198			register int i, j;
199			/* get/check arguments */
200			co = getcone(ob, 0);
201			/* set up sampling */
202			n = PI * il->sampdens;
203			nalt = sqrt(n/PI) + .5;
204			nazi = PI*nalt + .5;
205			n = nalt*nazi;
206			distarr = (float )calloc(n, 3sizeof(float));
207			if (distarr == NULL)
208			error(SYSTEM, "out of memory in o_ring");
209			mkaxes(u, v, co->ad);
210			dim[0] = random();
211			/* sample disk */
212			for (dim[1] = 0; dim[1] < nalt; dim[1]++)
213			for (dim[2] = 0; dim[2] < nazi; dim[2]++)
214			for (i = 0; i < il->nsamps; i++) {
215			/* random direction */
216			dim[3] = 1;
217			r1 = (dim[1]+urand(urind(ilhash(dim,4),i)))/nalt;
218			dim[3] = 2;
219			r2 = (dim[2]+urand(urind(ilhash(dim,4),i)))/nalt;
220			flatdir(dn, r1, r2);
221			for (j = 0; j < 3; j++)
222			dir[j] = dn[0]u[j] + dn[1]v[j] - dn[2]*co->ad[j];
223			/* random location */
224			dim[3] = 3;
225			r1 = sqrt(CO_R0(co)*CO_R0(co) +
226			urand(urind(ilhash(dim,4),i))*
227			(CO_R1(co)CO_R1(co) - CO_R0(co)CO_R0(co)));
228			dim[3] = 4;
229			r2 = 2.PIurand(urind(ilhash(dim,4),i));
230			for (j = 0; j < 3; j++)
231			org[j] = CO_P0(co)[j] +
232			r1cos(r2)u[j] + r1sin(r2)v[j]
233			+ .001*co->ad[j];
234
235			/* send sample */
236			raysamp(distarr+dim[1]*nazi+dim[2], org, dir, rt);
237			}
238			rayflush(rt);
239	greg	1.4	/* write out the ring w/ distribution */
240			flatout(il, distarr, nalt, nazi, u, v, co->ad);
241			illumout(il, ob);
242	greg	1.3	/* clean up */
243			freecone(ob);
244			free((char *)distarr);
245	greg	1.2	}
246
247
248			raysamp(res, org, dir, rt) /* compute a ray sample */
249			float res[3];
250			FVECT org, dir;
251			register struct rtproc *rt;
252			{
253			register float *fp;
254
255			if (rt->nrays == rt->bsiz)
256			rayflush(rt);
257			rt->dest[rt->nrays] = res;
258			fp = rt->buf + 6*rt->nrays++;
259			fp++ = org[0]; fp++ = org[1]; *fp++ = org[2];
260			fp++ = dir[0]; fp++ = dir[1]; *fp = dir[2];
261			}
262
263
264			rayflush(rt) /* flush buffered rays */
265			register struct rtproc *rt;
266			{
267			register int i;
268
269			if (rt->nrays <= 0)
270			return;
271			i = 6*rt->nrays + 3;
272			rt->buf[i++] = 0.; rt->buf[i++] = 0.; rt->buf[i] = 0.;
273			if ( process(rt->pd, (char )rt->buf, (char )rt->buf,
274			3sizeof(float)rt->nrays,
275			6sizeof(float)(rt->nrays+1)) <
276			3sizeof(float)rt->nrays )
277			error(SYSTEM, "error reading from rtrace process");
278			i = rt->nrays;
279			while (i--) {
280			rt->dest[i][0] += rt->buf[3*i];
281			rt->dest[i][1] += rt->buf[3*i+1];
282			rt->dest[i][2] += rt->buf[3*i+2];
283			}
284			rt->nrays = 0;
285	greg	1.4	}
286
287
288			mkaxes(u, v, n) /* compute u and v to go with n */
289			FVECT u, v, n;
290			{
291			register int i;
292
293			v[0] = v[1] = v[2] = 0.0;
294			for (i = 0; i < 3; i++)
295			if (n[i] < 0.6 && n[i] > -0.6)
296			break;
297			v[i] = 1.0;
298			fcross(u, v, n);
299			normalize(u);
300			fcross(v, n, u);
301			}
302
303
304			rounddir(dv, alt, azi) /* compute uniform spherical direction */
305			register FVECT dv;
306			double alt, azi;
307			{
308			double d1, d2;
309
310			dv[2] = 1. - 2.*alt;
311			d1 = sqrt(1. - dv[2]*dv[2]);
312			d2 = 2.PI azi;
313			dv[0] = d1*cos(d2);
314			dv[1] = d1*sin(d2);
315			}
316
317
318			flatdir(dv, alt, azi) /* compute uniform hemispherical direction */
319			register FVECT dv;
320			double alt, azi;
321			{
322			double d1, d2;
323
324			d1 = sqrt(alt);
325			d2 = 2.PI azi;
326			dv[0] = d1*cos(d2);
327			dv[1] = d1*sin(d2);
328			dv[2] = sqrt(1. - d1*d1);
329	greg	1.1	}