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/* Copyright (c) 1991 Regents of the University of California */ |
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#ifndef lint |
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static char SCCSid[] = "$SunId$ LBL"; |
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static const char RCSid[] = "$Id$"; |
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#endif |
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|
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/* |
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* Support routines for source objects and materials |
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* |
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* External symbols declared in source.h |
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*/ |
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#include "copyright.h" |
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#include "ray.h" |
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#include "otypes.h" |
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#include "face.h" |
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#define SRCINC 4 /* realloc increment for array */ |
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SRCREC *source = NULL; /* our list of sources */ |
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int nsources = 0; /* the number of sources */ |
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SRCFUNC sfun[NUMOTYPE]; /* source dispatch table */ |
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void |
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initstypes() /* initialize source dispatch table */ |
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{ |
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extern VSMATERIAL mirror_vs; |
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extern int fsetsrc(), ssetsrc(), sphsetsrc(), rsetsrc(); |
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extern double fgetplaneq(), rgetplaneq(); |
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extern double fgetmaxdisk(), rgetmaxdisk(); |
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static SOBJECT fsobj = {fsetsrc, fgetplaneq, fgetmaxdisk}; |
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static SOBJECT ssobj = {ssetsrc}; |
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static SOBJECT sphsobj = {sphsetsrc}; |
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static SOBJECT rsobj = {rsetsrc, rgetplaneq, rgetmaxdisk}; |
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extern VSMATERIAL mirror_vs, direct1_vs, direct2_vs; |
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static SOBJECT fsobj = {fsetsrc, flatpart, fgetplaneq, fgetmaxdisk}; |
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static SOBJECT ssobj = {ssetsrc, nopart}; |
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static SOBJECT sphsobj = {sphsetsrc, nopart}; |
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static SOBJECT cylsobj = {cylsetsrc, cylpart}; |
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static SOBJECT rsobj = {rsetsrc, flatpart, rgetplaneq, rgetmaxdisk}; |
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|
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sfun[MAT_MIRROR].mf = &mirror_vs; |
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sfun[MAT_DIRECT1].mf = &direct1_vs; |
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sfun[MAT_DIRECT2].mf = &direct2_vs; |
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sfun[OBJ_FACE].of = &fsobj; |
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sfun[OBJ_SOURCE].of = &ssobj; |
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sfun[OBJ_SPHERE].of = &sphsobj; |
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sfun[OBJ_CYLINDER].of = &cylsobj; |
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sfun[OBJ_RING].of = &rsobj; |
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} |
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newsource() /* allocate new source in our array */ |
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{ |
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if (nsources == 0) |
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source = (SRCREC *)malloc(sizeof(SRCREC)); |
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else |
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source = (SRCREC *)realloc((char *)source, |
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(unsigned)(nsources+1)*sizeof(SRCREC)); |
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source = (SRCREC *)malloc(SRCINC*sizeof(SRCREC)); |
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else if (nsources%SRCINC == 0) |
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source = (SRCREC *)realloc((void *)source, |
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(unsigned)(nsources+SRCINC)*sizeof(SRCREC)); |
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if (source == NULL) |
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return(-1); |
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source[nsources].sflags = 0; |
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} |
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void |
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setflatss(src) /* set sampling for a flat source */ |
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register SRCREC *src; |
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{ |
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double mult; |
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register int i; |
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|
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src->ss[SV][0] = src->ss[SV][1] = src->ss[SV][2] = 0.0; |
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for (i = 0; i < 3; i++) |
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if (src->snorm[i] < 0.6 && src->snorm[i] > -0.6) |
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break; |
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src->ss[SV][i] = 1.0; |
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fcross(src->ss[SU], src->ss[SV], src->snorm); |
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mult = .5 * sqrt( src->ss2 / DOT(src->ss[SU],src->ss[SU]) ); |
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for (i = 0; i < 3; i++) |
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src->ss[SU][i] *= mult; |
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fcross(src->ss[SV], src->snorm, src->ss[SU]); |
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} |
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|
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|
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void |
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fsetsrc(src, so) /* set a face as a source */ |
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register SRCREC *src; |
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OBJREC *so; |
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{ |
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register FACE *f; |
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register int i, j; |
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double d; |
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src->sa.success = 2*AIMREQT-1; /* bitch on second failure */ |
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src->so = so; |
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objerror(so, USER, "cannot hit center"); |
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src->sflags |= SFLAT; |
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VCOPY(src->snorm, f->norm); |
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src->ss = sqrt(f->area / PI); |
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src->ss2 = f->area; |
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/* find maximum radius */ |
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src->srad = 0.; |
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for (i = 0; i < f->nv; i++) { |
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d = dist2(VERTEX(f,i), src->sloc); |
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if (d > src->srad) |
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src->srad = d; |
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} |
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src->srad = sqrt(src->srad); |
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/* compute size vectors */ |
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if (f->nv == 4) /* parallelogram case */ |
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for (j = 0; j < 3; j++) { |
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src->ss[SU][j] = .5*(VERTEX(f,1)[j]-VERTEX(f,0)[j]); |
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src->ss[SV][j] = .5*(VERTEX(f,3)[j]-VERTEX(f,0)[j]); |
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} |
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else |
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setflatss(src); |
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} |
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void |
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ssetsrc(src, so) /* set a source as a source */ |
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register SRCREC *src; |
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register OBJREC *so; |
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theta = PI/180.0/2.0 * so->oargs.farg[3]; |
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if (theta <= FTINY) |
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objerror(so, USER, "zero size"); |
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src->ss = theta >= PI/4 ? 1.0 : tan(theta); |
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src->ss2 = 2.0*PI * (1.0 - cos(theta)); |
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/* the following is approximate */ |
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src->srad = sqrt(src->ss2/PI); |
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VCOPY(src->snorm, src->sloc); |
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setflatss(src); /* hey, whatever works */ |
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src->ss[SW][0] = src->ss[SW][1] = src->ss[SW][2] = 0.0; |
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} |
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void |
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sphsetsrc(src, so) /* set a sphere as a source */ |
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register SRCREC *src; |
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register OBJREC *so; |
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{ |
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register int i; |
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|
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src->sa.success = 2*AIMREQT-1; /* bitch on second failure */ |
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src->so = so; |
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if (so->oargs.nfargs != 4) |
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if (so->oargs.farg[3] <= FTINY) |
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objerror(so, USER, "illegal radius"); |
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VCOPY(src->sloc, so->oargs.farg); |
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src->ss = so->oargs.farg[3]; |
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src->ss2 = PI * src->ss * src->ss; |
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src->srad = so->oargs.farg[3]; |
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src->ss2 = PI * src->srad * src->srad; |
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for (i = 0; i < 3; i++) |
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src->ss[SU][i] = src->ss[SV][i] = src->ss[SW][i] = 0.0; |
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for (i = 0; i < 3; i++) |
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src->ss[i][i] = .7236 * so->oargs.farg[3]; |
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} |
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void |
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rsetsrc(src, so) /* set a ring (disk) as a source */ |
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register SRCREC *src; |
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OBJREC *so; |
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objerror(so, USER, "cannot hit center"); |
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src->sflags |= SFLAT; |
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VCOPY(src->snorm, co->ad); |
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src->ss = CO_R1(co); |
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src->ss2 = PI * src->ss * src->ss; |
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src->srad = CO_R1(co); |
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src->ss2 = PI * src->srad * src->srad; |
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setflatss(src); |
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} |
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|
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void |
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cylsetsrc(src, so) /* set a cylinder as a source */ |
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register SRCREC *src; |
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OBJREC *so; |
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{ |
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register CONE *co; |
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register int i; |
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|
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src->sa.success = 4*AIMREQT-1; /* bitch on fourth failure */ |
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src->so = so; |
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/* get the cylinder */ |
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co = getcone(so, 0); |
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if (CO_R0(co) > .2*co->al) /* heuristic constraint */ |
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objerror(so, WARNING, "source aspect too small"); |
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src->sflags |= SCYL; |
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for (i = 0; i < 3; i++) |
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src->sloc[i] = .5 * (CO_P1(co)[i] + CO_P0(co)[i]); |
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src->srad = .5*co->al; |
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src->ss2 = 2.*CO_R0(co)*co->al; |
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/* set sampling vectors */ |
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for (i = 0; i < 3; i++) |
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src->ss[SU][i] = .5 * co->al * co->ad[i]; |
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src->ss[SV][0] = src->ss[SV][1] = src->ss[SV][2] = 0.0; |
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for (i = 0; i < 3; i++) |
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if (co->ad[i] < 0.6 && co->ad[i] > -0.6) |
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break; |
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src->ss[SV][i] = 1.0; |
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fcross(src->ss[SW], src->ss[SV], co->ad); |
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normalize(src->ss[SW]); |
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for (i = 0; i < 3; i++) |
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src->ss[SW][i] *= .8559 * CO_R0(co); |
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fcross(src->ss[SV], src->ss[SW], co->ad); |
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} |
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|
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|
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SPOT * |
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makespot(m) /* make a spotlight */ |
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register OBJREC *m; |
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{ |
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extern double cos(); |
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register SPOT *ns; |
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if ((ns = (SPOT *)m->os) != NULL) |
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return(ns); |
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if ((ns = (SPOT *)malloc(sizeof(SPOT))) == NULL) |
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return(NULL); |
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ns->siz = 2.0*PI * (1.0 - cos(PI/180.0/2.0 * m->oargs.farg[3])); |
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VCOPY(ns->aim, m->oargs.farg+4); |
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if ((ns->flen = normalize(ns->aim)) == 0.0) |
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objerror(m, USER, "zero focus vector"); |
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m->os = (char *)ns; |
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return(ns); |
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} |
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|
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int |
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spotout(r, s) /* check if we're outside spot region */ |
260 |
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register RAY *r; |
261 |
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register SPOT *s; |
262 |
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{ |
263 |
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double d; |
264 |
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FVECT vd; |
265 |
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|
266 |
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if (s == NULL) |
267 |
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return(0); |
268 |
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if (s->flen < -FTINY) { /* distant source */ |
269 |
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vd[0] = s->aim[0] - r->rorg[0]; |
270 |
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vd[1] = s->aim[1] - r->rorg[1]; |
271 |
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vd[2] = s->aim[2] - r->rorg[2]; |
272 |
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d = DOT(r->rdir,vd); |
273 |
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/* wrong side? |
274 |
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if (d <= FTINY) |
275 |
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return(1); */ |
276 |
+ |
d = DOT(vd,vd) - d*d; |
277 |
+ |
if (PI*d > s->siz) |
278 |
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return(1); /* out */ |
279 |
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return(0); /* OK */ |
280 |
+ |
} |
281 |
+ |
/* local source */ |
282 |
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if (s->siz < 2.0*PI * (1.0 + DOT(s->aim,r->rdir))) |
283 |
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return(1); /* out */ |
284 |
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return(0); /* OK */ |
285 |
+ |
} |
286 |
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|
287 |
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|
288 |
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double |
289 |
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fgetmaxdisk(ocent, op) /* get center and squared radius of face */ |
290 |
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FVECT ocent; |
291 |
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OBJREC *op; |
292 |
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{ |
293 |
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double maxrad2; |
294 |
< |
double d2; |
294 |
> |
double d; |
295 |
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register int i, j; |
296 |
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register FACE *f; |
297 |
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|
298 |
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f = getface(op); |
299 |
+ |
if (f->area == 0.) |
300 |
+ |
return(0.); |
301 |
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for (i = 0; i < 3; i++) { |
302 |
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ocent[i] = 0.; |
303 |
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for (j = 0; j < f->nv; j++) |
304 |
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ocent[i] += VERTEX(f,j)[i]; |
305 |
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ocent[i] /= (double)f->nv; |
306 |
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} |
307 |
+ |
d = DOT(ocent,f->norm); |
308 |
+ |
for (i = 0; i < 3; i++) |
309 |
+ |
ocent[i] += (f->offset - d)*f->norm[i]; |
310 |
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maxrad2 = 0.; |
311 |
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for (j = 0; j < f->nv; j++) { |
312 |
< |
d2 = dist2(VERTEX(f,j), ocent); |
313 |
< |
if (d2 > maxrad2) |
314 |
< |
maxrad2 = d2; |
312 |
> |
d = dist2(VERTEX(f,j), ocent); |
313 |
> |
if (d > maxrad2) |
314 |
> |
maxrad2 = d; |
315 |
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} |
316 |
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return(maxrad2); |
317 |
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} |
356 |
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} |
357 |
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|
358 |
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|
359 |
< |
sourcehit(r) /* check to see if ray hit distant source */ |
360 |
< |
register RAY *r; |
359 |
> |
int |
360 |
> |
commonspot(sp1, sp2, org) /* set sp1 to intersection of sp1 and sp2 */ |
361 |
> |
register SPOT *sp1, *sp2; |
362 |
> |
FVECT org; |
363 |
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{ |
364 |
< |
int first, last; |
364 |
> |
FVECT cent; |
365 |
> |
double rad2, cos1, cos2; |
366 |
> |
|
367 |
> |
cos1 = 1. - sp1->siz/(2.*PI); |
368 |
> |
cos2 = 1. - sp2->siz/(2.*PI); |
369 |
> |
if (sp2->siz >= 2.*PI-FTINY) /* BIG, just check overlap */ |
370 |
> |
return(DOT(sp1->aim,sp2->aim) >= cos1*cos2 - |
371 |
> |
sqrt((1.-cos1*cos1)*(1.-cos2*cos2))); |
372 |
> |
/* compute and check disks */ |
373 |
> |
rad2 = intercircle(cent, sp1->aim, sp2->aim, |
374 |
> |
1./(cos1*cos1) - 1., 1./(cos2*cos2) - 1.); |
375 |
> |
if (rad2 <= FTINY || normalize(cent) == 0.) |
376 |
> |
return(0); |
377 |
> |
VCOPY(sp1->aim, cent); |
378 |
> |
sp1->siz = 2.*PI*(1. - 1./sqrt(1.+rad2)); |
379 |
> |
return(1); |
380 |
> |
} |
381 |
> |
|
382 |
> |
|
383 |
> |
int |
384 |
> |
commonbeam(sp1, sp2, dir) /* set sp1 to intersection of sp1 and sp2 */ |
385 |
> |
register SPOT *sp1, *sp2; |
386 |
> |
FVECT dir; |
387 |
> |
{ |
388 |
> |
FVECT cent, c1, c2; |
389 |
> |
double rad2, d; |
390 |
|
register int i; |
391 |
+ |
/* move centers to common plane */ |
392 |
+ |
d = DOT(sp1->aim, dir); |
393 |
+ |
for (i = 0; i < 3; i++) |
394 |
+ |
c1[i] = sp1->aim[i] - d*dir[i]; |
395 |
+ |
d = DOT(sp2->aim, dir); |
396 |
+ |
for (i = 0; i < 3; i++) |
397 |
+ |
c2[i] = sp2->aim[i] - d*dir[i]; |
398 |
+ |
/* compute overlap */ |
399 |
+ |
rad2 = intercircle(cent, c1, c2, sp1->siz/PI, sp2->siz/PI); |
400 |
+ |
if (rad2 <= FTINY) |
401 |
+ |
return(0); |
402 |
+ |
VCOPY(sp1->aim, cent); |
403 |
+ |
sp1->siz = PI*rad2; |
404 |
+ |
return(1); |
405 |
+ |
} |
406 |
|
|
238 |
– |
if (r->rsrc >= 0) { /* check only one if aimed */ |
239 |
– |
first = last = r->rsrc; |
240 |
– |
} else { /* otherwise check all */ |
241 |
– |
first = 0; last = nsources-1; |
242 |
– |
} |
243 |
– |
for (i = first; i <= last; i++) |
244 |
– |
if (source[i].sflags & SDISTANT) |
245 |
– |
/* |
246 |
– |
* Check to see if ray is within |
247 |
– |
* solid angle of source. |
248 |
– |
*/ |
249 |
– |
if (2.0*PI * (1.0 - DOT(source[i].sloc,r->rdir)) |
250 |
– |
<= source[i].ss2) { |
251 |
– |
r->ro = source[i].so; |
252 |
– |
if (!(source[i].sflags & SSKIP)) |
253 |
– |
break; |
254 |
– |
} |
407 |
|
|
408 |
< |
if (r->ro != NULL) { |
409 |
< |
for (i = 0; i < 3; i++) |
410 |
< |
r->ron[i] = -r->rdir[i]; |
411 |
< |
r->rod = 1.0; |
412 |
< |
r->rox = NULL; |
408 |
> |
int |
409 |
> |
checkspot(sp, nrm) /* check spotlight for behind source */ |
410 |
> |
register SPOT *sp; /* spotlight */ |
411 |
> |
FVECT nrm; /* source surface normal */ |
412 |
> |
{ |
413 |
> |
double d, d1; |
414 |
> |
|
415 |
> |
d = DOT(sp->aim, nrm); |
416 |
> |
if (d > FTINY) /* center in front? */ |
417 |
|
return(1); |
418 |
< |
} |
419 |
< |
return(0); |
418 |
> |
/* else check horizon */ |
419 |
> |
d1 = 1. - sp->siz/(2.*PI); |
420 |
> |
return(1.-FTINY-d*d < d1*d1); |
421 |
|
} |
422 |
|
|
423 |
|
|
424 |
< |
#define wrongsource(m, r) (m->otype!=MAT_ILLUM && \ |
425 |
< |
r->rsrc>=0 && \ |
426 |
< |
source[r->rsrc].so!=r->ro) |
424 |
> |
double |
425 |
> |
spotdisk(oc, op, sp, pos) /* intersect spot with object op */ |
426 |
> |
FVECT oc; |
427 |
> |
OBJREC *op; |
428 |
> |
register SPOT *sp; |
429 |
> |
FVECT pos; |
430 |
> |
{ |
431 |
> |
FVECT onorm; |
432 |
> |
double offs, d, dist; |
433 |
> |
register int i; |
434 |
|
|
435 |
< |
#define badambient(m, r) ((r->crtype&(AMBIENT|SHADOW))==AMBIENT && \ |
436 |
< |
!(m->otype==MAT_GLOW&&r->rot>m->oargs.farg[3])) |
435 |
> |
offs = getplaneq(onorm, op); |
436 |
> |
d = -DOT(onorm, sp->aim); |
437 |
> |
if (d >= -FTINY && d <= FTINY) |
438 |
> |
return(0.); |
439 |
> |
dist = (DOT(pos, onorm) - offs)/d; |
440 |
> |
if (dist < 0.) |
441 |
> |
return(0.); |
442 |
> |
for (i = 0; i < 3; i++) |
443 |
> |
oc[i] = pos[i] + dist*sp->aim[i]; |
444 |
> |
return(sp->siz*dist*dist/PI/(d*d)); |
445 |
> |
} |
446 |
|
|
274 |
– |
#define passillum(m, r) (m->otype==MAT_ILLUM && \ |
275 |
– |
!(r->rsrc>=0&&source[r->rsrc].so==r->ro)) |
447 |
|
|
448 |
< |
|
449 |
< |
m_light(m, r) /* ray hit a light source */ |
450 |
< |
register OBJREC *m; |
451 |
< |
register RAY *r; |
448 |
> |
double |
449 |
> |
beamdisk(oc, op, sp, dir) /* intersect beam with object op */ |
450 |
> |
FVECT oc; |
451 |
> |
OBJREC *op; |
452 |
> |
register SPOT *sp; |
453 |
> |
FVECT dir; |
454 |
|
{ |
455 |
< |
/* check for over-counting */ |
456 |
< |
if (wrongsource(m, r) || badambient(m, r)) |
457 |
< |
return; |
285 |
< |
/* check for passed illum */ |
286 |
< |
if (passillum(m, r)) { |
455 |
> |
FVECT onorm; |
456 |
> |
double offs, d, dist; |
457 |
> |
register int i; |
458 |
|
|
459 |
< |
if (m->oargs.nsargs < 1 || !strcmp(m->oargs.sarg[0], VOIDID)) |
460 |
< |
raytrans(r); |
461 |
< |
else |
462 |
< |
rayshade(r, modifier(m->oargs.sarg[0])); |
459 |
> |
offs = getplaneq(onorm, op); |
460 |
> |
d = -DOT(onorm, dir); |
461 |
> |
if (d >= -FTINY && d <= FTINY) |
462 |
> |
return(0.); |
463 |
> |
dist = (DOT(sp->aim, onorm) - offs)/d; |
464 |
> |
for (i = 0; i < 3; i++) |
465 |
> |
oc[i] = sp->aim[i] + dist*dir[i]; |
466 |
> |
return(sp->siz/PI/(d*d)); |
467 |
> |
} |
468 |
|
|
469 |
< |
/* otherwise treat as source */ |
469 |
> |
|
470 |
> |
double |
471 |
> |
intercircle(cc, c1, c2, r1s, r2s) /* intersect two circles */ |
472 |
> |
FVECT cc; /* midpoint (return value) */ |
473 |
> |
FVECT c1, c2; /* circle centers */ |
474 |
> |
double r1s, r2s; /* radii squared */ |
475 |
> |
{ |
476 |
> |
double a2, d2, l; |
477 |
> |
FVECT disp; |
478 |
> |
register int i; |
479 |
> |
|
480 |
> |
for (i = 0; i < 3; i++) |
481 |
> |
disp[i] = c2[i] - c1[i]; |
482 |
> |
d2 = DOT(disp,disp); |
483 |
> |
/* circle within overlap? */ |
484 |
> |
if (r1s < r2s) { |
485 |
> |
if (r2s >= r1s + d2) { |
486 |
> |
VCOPY(cc, c1); |
487 |
> |
return(r1s); |
488 |
> |
} |
489 |
|
} else { |
490 |
< |
/* check for behind */ |
491 |
< |
if (r->rod < 0.0) |
492 |
< |
return; |
493 |
< |
/* get distribution pattern */ |
299 |
< |
raytexture(r, m->omod); |
300 |
< |
/* get source color */ |
301 |
< |
setcolor(r->rcol, m->oargs.farg[0], |
302 |
< |
m->oargs.farg[1], |
303 |
< |
m->oargs.farg[2]); |
304 |
< |
/* modify value */ |
305 |
< |
multcolor(r->rcol, r->pcol); |
490 |
> |
if (r1s >= r2s + d2) { |
491 |
> |
VCOPY(cc, c2); |
492 |
> |
return(r2s); |
493 |
> |
} |
494 |
|
} |
495 |
+ |
a2 = .25*(2.*(r1s+r2s) - d2 - (r2s-r1s)*(r2s-r1s)/d2); |
496 |
+ |
/* no overlap? */ |
497 |
+ |
if (a2 <= 0.) |
498 |
+ |
return(0.); |
499 |
+ |
/* overlap, compute center */ |
500 |
+ |
l = sqrt((r1s - a2)/d2); |
501 |
+ |
for (i = 0; i < 3; i++) |
502 |
+ |
cc[i] = c1[i] + l*disp[i]; |
503 |
+ |
return(a2); |
504 |
|
} |