| 1 | gwlarson | 3.1 | /* Copyright (c) 1999 Silicon Graphics, Inc. */ | 
| 2 |  |  |  | 
| 3 |  |  | #ifndef lint | 
| 4 |  |  | static char SCCSid[] = "$SunId$ SGI"; | 
| 5 |  |  | #endif | 
| 6 |  |  |  | 
| 7 |  |  | /* | 
| 8 |  |  | * Convert view to beam list. | 
| 9 |  |  | */ | 
| 10 |  |  |  | 
| 11 |  |  | #include "rholo.h" | 
| 12 |  |  | #include "view.h" | 
| 13 |  |  | #include "random.h" | 
| 14 |  |  |  | 
| 15 |  |  | #ifndef MINRES | 
| 16 |  |  | #define MINRES          12              /* section sample resolution */ | 
| 17 |  |  | #endif | 
| 18 |  |  | #ifndef NVSAMPS | 
| 19 |  |  | #define NVSAMPS         16384           /* target number of view samples */ | 
| 20 |  |  | #endif | 
| 21 |  |  |  | 
| 22 |  |  | #define OJITTER         0.25            /* amount to jitter sample origin */ | 
| 23 |  |  |  | 
| 24 |  |  | #define BALLOCBLK       128             /* beam allocation block size */ | 
| 25 |  |  |  | 
| 26 |  |  |  | 
| 27 |  |  | static BEAMLIST blist; | 
| 28 |  |  |  | 
| 29 |  |  |  | 
| 30 |  |  | static | 
| 31 |  |  | add2blist(hd, bi, nr)                   /* add to beam sample list */ | 
| 32 |  |  | int     hd, bi, nr; | 
| 33 |  |  | { | 
| 34 |  |  | register int    i; | 
| 35 |  |  |  | 
| 36 |  |  | for (i = blist.nb; i--; ) | 
| 37 |  |  | if (blist.bl[i].bi == bi && blist.bl[i].hd == hd) { | 
| 38 |  |  | blist.bl[i].nr += nr;   /* found it */ | 
| 39 |  |  | return; | 
| 40 |  |  | } | 
| 41 |  |  | i = blist.nb++;                         /* else add beam to list */ | 
| 42 |  |  | if (i % BALLOCBLK == 0) { | 
| 43 |  |  | blist.bl = (PACKHEAD *)realloc((char *)blist.bl, | 
| 44 |  |  | (i+BALLOCBLK)*sizeof(PACKHEAD)); | 
| 45 |  |  | CHECK(blist.bl==NULL, SYSTEM, "out of memory in add2blist"); | 
| 46 |  |  | } | 
| 47 |  |  | blist.bl[i].hd = hd; blist.bl[i].bi = bi; | 
| 48 |  |  | blist.bl[i].nr = nr; blist.bl[i].nc = 0; | 
| 49 |  |  | } | 
| 50 |  |  |  | 
| 51 |  |  |  | 
| 52 |  |  | int2 * | 
| 53 |  |  | viewbeams(vp, hr, vr, blp)              /* convert view into sections/beams */ | 
| 54 |  |  | VIEW    *vp; | 
| 55 |  |  | int     hr, vr; | 
| 56 |  |  | BEAMLIST        *blp; | 
| 57 |  |  | { | 
| 58 |  |  | static int2     sectlist[HDMAX+1]; | 
| 59 |  |  | int2    sectarr[MINRES+1][MINRES+1]; | 
| 60 |  |  | double  d0, d1, mindist; | 
| 61 |  |  | GCOORD  gc[2]; | 
| 62 |  |  | FVECT   rorg, rdir; | 
| 63 |  |  | int     shr, svr, sampquant; | 
| 64 |  |  | int     v; | 
| 65 |  |  | register int    h, hd; | 
| 66 |  |  | /* clear section flags */ | 
| 67 |  |  | bzero((char *)sectlist, sizeof(sectlist)); | 
| 68 |  |  | /* identify view sections */ | 
| 69 |  |  | for (v = 0; v <= MINRES; v++) | 
| 70 |  |  | for (h = 0; h <= MINRES; h++) { | 
| 71 |  |  | sectarr[v][h] = -1; | 
| 72 |  |  | mindist = 0.99*FHUGE; | 
| 73 |  |  | if (viewray(rorg, rdir, vp, (double)h/MINRES, | 
| 74 |  |  | (double)v/MINRES) < -FTINY) | 
| 75 |  |  | continue; | 
| 76 |  |  | for (hd = 0; hdlist[hd] != NULL; hd++) { | 
| 77 |  |  | d0 = hdinter(gc, NULL, &d1, | 
| 78 |  |  | hdlist[hd], rorg, rdir); | 
| 79 |  |  | if (d0 >= 0.99*FHUGE) | 
| 80 |  |  | continue;               /* missed */ | 
| 81 |  |  | if (d0 <= 0. && d1 >= 0.) { | 
| 82 |  |  | sectarr[v][h] = hd; | 
| 83 |  |  | break;                  /* inside */ | 
| 84 |  |  | } | 
| 85 |  |  | if (d0 > 0. && d0 < mindist) { | 
| 86 |  |  | sectarr[v][h] = hd; | 
| 87 |  |  | mindist = d0; | 
| 88 |  |  | } else if (d1 < 0. && -d1 < mindist) { | 
| 89 |  |  | sectarr[v][h] = hd; | 
| 90 |  |  | mindist = -d1; | 
| 91 |  |  | } | 
| 92 |  |  | } | 
| 93 |  |  | if ((hd = sectarr[v][h]) >= 0) | 
| 94 |  |  | sectlist[hd]++;         /* flag section */ | 
| 95 |  |  | } | 
| 96 |  |  | /* convert flags to list */ | 
| 97 |  |  | for (h = hd = 0; hdlist[hd] != NULL; h++, hd++) { | 
| 98 |  |  | while (!sectlist[hd]) | 
| 99 |  |  | if (hdlist[++hd] == NULL) | 
| 100 |  |  | goto loopexit; | 
| 101 |  |  | sectlist[h] = hd; | 
| 102 |  |  | } | 
| 103 |  |  | loopexit: | 
| 104 |  |  | sectlist[h] = -1;                       /* list terminator */ | 
| 105 |  |  | if (blp == NULL)                        /* if no beam list... */ | 
| 106 |  |  | return(sectlist);                       /* return early */ | 
| 107 |  |  | /* else set up sampling */ | 
| 108 |  |  | if (hr|vr && hr*vr <= NVSAMPS) { | 
| 109 |  |  | shr = hr; svr = vr; | 
| 110 |  |  | sampquant = 1; | 
| 111 |  |  | } else { | 
| 112 |  |  | shr = sqrt(NVSAMPS/viewaspect(vp)) + .5; | 
| 113 |  |  | svr = (NVSAMPS + shr/2)/shr; | 
| 114 |  |  | sampquant = (hr*vr + shr*svr/2)/(shr*svr); | 
| 115 |  |  | } | 
| 116 |  |  | blist.bl = NULL; blist.nb = 0;          /* sample view rays */ | 
| 117 |  |  | for (v = svr; v--; ) | 
| 118 |  |  | for (h = shr; h--; ) { | 
| 119 |  |  | hd = random()>>6 & 03;          /* get section */ | 
| 120 |  |  | hd = sectarr[v*MINRES/svr + (hd&01)] | 
| 121 |  |  | [h*MINRES/shr + (hd>>1)]; | 
| 122 |  |  | if (hd < 0) | 
| 123 |  |  | continue; | 
| 124 |  |  | /* get sample ray */ | 
| 125 |  |  | if (viewray(rorg, rdir, vp, (h+frandom())/shr, | 
| 126 |  |  | (v+frandom())/svr) < -FTINY) | 
| 127 |  |  | continue; | 
| 128 |  |  | #ifdef OJITTER | 
| 129 |  |  | /* jitter origin */ | 
| 130 |  |  | d0 = OJITTER*(frandom() - .5) / hdlist[hd]->grid[0]; | 
| 131 |  |  | VSUM(rorg, rorg, hdlist[hd]->xv[0], d0); | 
| 132 |  |  | d0 = OJITTER*(frandom() - .5) / hdlist[hd]->grid[1]; | 
| 133 |  |  | VSUM(rorg, rorg, hdlist[hd]->xv[1], d0); | 
| 134 |  |  | d0 = OJITTER*(frandom() - .5) / hdlist[hd]->grid[2]; | 
| 135 |  |  | VSUM(rorg, rorg, hdlist[hd]->xv[2], d0); | 
| 136 |  |  | #endif | 
| 137 |  |  | /* intersect section */ | 
| 138 |  |  | if (hdinter(gc, NULL, NULL, hdlist[hd], rorg, rdir) | 
| 139 |  |  | >= 0.99*FHUGE) | 
| 140 |  |  | continue; | 
| 141 |  |  | /* add samples */ | 
| 142 |  |  | add2blist(hd, hdbindex(hdlist[hd],gc), sampquant); | 
| 143 |  |  | } | 
| 144 |  |  | copystruct(blp, &blist);                /* transfer beam list */ | 
| 145 |  |  | return(sectlist);                       /* all done! */ | 
| 146 |  |  | } | 
| 147 |  |  |  | 
| 148 |  |  |  | 
| 149 |  |  | int | 
| 150 |  |  | nextview(vp, fp)                        /* get next view from fp */ | 
| 151 |  |  | VIEW    *vp; | 
| 152 |  |  | FILE    *fp; | 
| 153 |  |  | { | 
| 154 |  |  | char    linebuf[256]; | 
| 155 |  |  |  | 
| 156 |  |  | while (fgets(linebuf, sizeof(linebuf), fp) != NULL) | 
| 157 |  |  | if (isview(linebuf) && sscanview(vp, linebuf) > 0) | 
| 158 |  |  | return(0); | 
| 159 |  |  | return(EOF); | 
| 160 |  |  | } |