| 1 |
/* Copyright (c) 1998 Silicon Graphics, Inc. */ |
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|
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#ifndef lint |
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static char SCCSid[] = "$SunId$ SGI"; |
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#endif |
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|
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/* |
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* Routines for drawing samples using depth buffer checks. |
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*/ |
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|
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#include "standard.h" |
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|
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#include <sys/types.h> |
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#include <GL/glx.h> |
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#include <GL/glu.h> |
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|
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#include "random.h" |
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#include "rhd_odraw.h" |
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|
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#ifndef DEPTHEPS |
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#define DEPTHEPS 0.02 /* depth epsilon */ |
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#endif |
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#ifndef SAMPSPERBLOCK |
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#define SAMPSPERBLOCK 1024 /* target samples per image block */ |
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#endif |
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#ifndef SFREEFRAC |
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#define SFREEFRAC 0.2 /* fraction to free at a time */ |
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#endif |
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#ifndef MAXFAN |
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#define MAXFAN 32 /* maximum arms in a triangle fan */ |
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#endif |
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#ifndef MINFAN |
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#define MINFAN 4 /* minimum arms in a triangle fan */ |
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#endif |
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#ifndef FANSIZE |
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#define FANSIZE 3.5 /* fan sizing factor */ |
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#endif |
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|
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#define NEWMAP 01 /* need to recompute mapping */ |
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#define NEWRGB 02 /* need to remap RGB values */ |
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|
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struct ODview *odView; /* our view list */ |
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int odNViews; /* number of views in our list */ |
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|
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struct ODsamp odS; /* sample values */ |
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|
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static int needmapping; /* what needs doing with tone map */ |
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|
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|
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#define SAMP32 (32*(2*sizeof(short)+sizeof(union ODfunion)+sizeof(TMbright)+\ |
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6*sizeof(BYTE))+sizeof(int4)) |
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|
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int |
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odInit(n) /* initialize drawing routines */ |
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int n; |
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{ |
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int nbytes, i, j, k, nextsamp, count, blockdiv; |
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int res[2]; |
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|
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if (odNViews) { /* deallocate view structures */ |
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for (i = 0; i < odNViews; i++) { |
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free((char *)odView[i].bmap); |
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if (odView[i].emap != NULL) |
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free((char *)odView[i].emap); |
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} |
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free((char *)odView); |
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odView = NULL; |
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odNViews = 0; |
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} |
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if (n && n != odS.nsamp) { |
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/* round space up to nearest power of 2 */ |
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nbytes = (n+31)/32 * SAMP32; |
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for (i = 1024; nbytes > i-8; i <<= 1) |
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; |
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n = (i-8)/SAMP32 * 32; |
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needmapping = NEWMAP; |
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} |
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if (n != odS.nsamp) { /* (re)allocate sample array */ |
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if (odS.nsamp) |
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free(odS.base); |
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odS.nsamp = 0; |
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if (!n) |
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return(0); |
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nbytes = (n+31)/32 * SAMP32; |
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odS.base = (char *)malloc(nbytes); |
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if (odS.base == NULL) |
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return(0); |
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/* assign larger alignment types earlier */ |
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odS.f = (union ODfunion *)odS.base; |
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odS.redraw = (int4 *)(odS.f + n); |
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odS.ip = (short (*)[2])(odS.redraw + n/32); |
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odS.brt = (TMbright *)(odS.ip + n); |
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odS.chr = (BYTE (*)[3])(odS.brt + n); |
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odS.rgb = (BYTE (*)[3])(odS.chr + n); |
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odS.nsamp = n; |
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} |
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if (!n) |
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return(0); |
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/* allocate view information */ |
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count = 0; /* count pixels */ |
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for (i = 0; dev_auxview(i, res) != NULL; i++) |
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count += res[0]*res[1]; |
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odView = (struct ODview *)malloc(i*sizeof(struct ODview)); |
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if (odView == NULL) |
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return(0); |
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odNViews = i; |
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blockdiv = sqrt(count/(n/SAMPSPERBLOCK)) + 0.5; |
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if (blockdiv < 8) blockdiv = 8; |
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nextsamp = 0; count /= blockdiv*blockdiv; /* # blocks */ |
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while (i--) { /* initialize each view */ |
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odView[i].emap = NULL; |
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odView[i].dmap = NULL; |
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dev_auxview(i, res); |
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odView[i].hhi = res[0]; |
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odView[i].hlow = (res[0] + blockdiv/2) / blockdiv; |
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if (odView[i].hlow < 1) odView[i].hlow = 1; |
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odView[i].vhi = res[1]; |
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odView[i].vlow = (res[1] + blockdiv/2) / blockdiv; |
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if (odView[i].vlow < 1) odView[i].vlow = 1; |
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j = odView[i].hlow*odView[i].vlow; |
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odView[i].bmap = (struct ODblock *)malloc( |
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j * sizeof(struct ODblock)); |
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if (odView[i].bmap == NULL) |
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return(0); |
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DCHECK(count<=0 | nextsamp>=n, |
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CONSISTENCY, "counter botch in odInit"); |
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if (!i) count = j; |
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while (j--) { |
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odView[i].bmap[j].first = k = nextsamp; |
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nextsamp += odView[i].bmap[j].nsamp = |
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(n - nextsamp)/count--; |
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odView[i].bmap[j].free = k; |
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while (++k < nextsamp) |
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odS.nextfree(k-1) = k; |
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odS.nextfree(k-1) = ENDFREE; |
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odView[i].bmap[j].nused = 0; |
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} |
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} |
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CLR4ALL(odS.redraw, odS.nsamp); /* clear redraw flags */ |
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for (i = odS.nsamp; i--; ) /* clear values */ |
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odS.ip[i][0] = odS.ip[i][1] = -1; |
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return(odS.nsamp); /* return number of samples */ |
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} |
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|
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#undef SAMP32 |
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|
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|
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int |
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sampcmp(s0, s1) /* sample order, descending proximity */ |
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int *s0, *s1; |
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{ |
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register double diff = odS.closeness(*s1) - odS.closeness(*s0); |
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|
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return (diff > FTINY ? 1 : diff < -FTINY ? -1 : 0); |
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} |
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|
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|
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int |
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odAllocBlockSamp(vn, hl, vl) /* allocate sample from block */ |
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int vn, hl, vl; |
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{ |
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int si[SAMPSPERBLOCK+SAMPSPERBLOCK/4]; |
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VIEW *vw; |
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FVECT ro, rd; |
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int res[2]; |
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register struct ODblock *bp; |
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register int i; |
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|
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bp = odView[vn].bmap + vl*odView[vn].hlow + hl; |
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if (bp->free != ENDFREE) { /* check free list first */ |
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i = bp->free; |
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bp->free = odS.nextfree(i); |
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bp->nused++; |
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return(i); |
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} |
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DCHECK(bp->nsamp<=0, CONSISTENCY, |
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"no available samples in odAllocBlockSamp"); |
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DCHECK(bp->nsamp > sizeof(si)/sizeof(si[0]), CONSISTENCY, |
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"too many samples in odAllocBlockSamp"); |
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/* free some samples */ |
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if ((vw = dev_auxview(vn, res)) == NULL) |
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error(CONSISTENCY, "bad view number in odAllocBlockSamp"); |
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for (i = bp->nsamp; i--; ) /* figure out which are worse */ |
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si[i] = bp->first + i; |
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qsort((char *)si, bp->nsamp, sizeof(int), sampcmp); |
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i = bp->nsamp*SFREEFRAC + .5; /* put them in a list */ |
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while (--i > 0) { |
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odS.nextfree(si[i]) = bp->free; |
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bp->free = si[i]; |
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bp->nused--; |
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} |
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return(si[0]); /* return first free sample */ |
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} |
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|
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|
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odSample(c, d, p) /* add a sample value */ |
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COLR c; |
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FVECT d, p; |
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{ |
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FVECT disp; |
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double d0, d1, h, v; |
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register VIEW *vw; |
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int hl, vl, hh, vh; |
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int res[2]; |
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register int i, id; |
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|
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DCHECK(odS.nsamp<=0, CONSISTENCY, "no samples allocated in odSample"); |
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/* add value to each view */ |
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for (i = 0; (vw = dev_auxview(i, res)) != NULL; i++) { |
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DCHECK(i>=odNViews, CONSISTENCY, "too many views in odSample"); |
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CHECK(vw->type!=VT_PER, INTERNAL, |
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"cannot handle non-perspective views"); |
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if (p != NULL) { /* compute view position */ |
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VSUB(disp, p, vw->vp); |
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d0 = DOT(disp, vw->vdir); |
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if (d0 <= vw->vfore+FTINY) |
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continue; /* too close */ |
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} else { |
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VCOPY(disp, d); |
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d0 = DOT(disp, vw->vdir); |
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if (d0 <= FTINY) /* behind view */ |
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continue; |
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} |
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h = DOT(disp,vw->hvec)/(d0*vw->hn2) + 0.5 - vw->hoff; |
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if (h < 0. || h >= 1.) |
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continue; /* left or right */ |
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v = DOT(disp,vw->vvec)/(d0*vw->vn2) + 0.5 - vw->voff; |
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if (v < 0. || v >= 1.) |
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continue; /* above or below */ |
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hh = h * res[0]; |
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vh = v * res[1]; |
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if (odView[i].dmap != NULL) { /* check depth */ |
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d1 = odView[i].dmap[vh*res[0] + hh]; |
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if (d1 < 0.99*FHUGE && (d0 > (1.+DEPTHEPS)*d1 || |
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(1.+DEPTHEPS)*d0 < d1)) |
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continue; /* occlusion error */ |
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} |
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hl = hh*odView[i].hlow/res[0]; |
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vl = vh*odView[i].vlow/res[1]; |
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/* may duplicate samples */ |
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id = odAllocBlockSamp(i, hl, vl); |
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odS.ip[id][0] = hh; |
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odS.ip[id][1] = vh; |
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if (p != NULL) { /* compute closeness (sin^2) */ |
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d1 = DOT(disp, d); |
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odS.closeness(id) = 1. - d1*d1/DOT(disp,disp); |
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} else |
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odS.closeness(id) = 0.; |
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/* convert color */ |
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tmCvColrs(&odS.brt[id], odS.chr[id], c, 1); |
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if (imm_mode | needmapping) /* if immediate mode */ |
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needmapping |= NEWRGB; /* map it later */ |
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else /* else map it now */ |
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tmMapPixels(odS.rgb[id], &odS.brt[id], odS.chr[id], 1); |
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SET4(odS.redraw, id); /* mark for redraw */ |
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} |
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} |
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|
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|
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odRemap() /* recompute tone mapping */ |
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{ |
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needmapping |= NEWMAP|NEWRGB; |
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} |
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|
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|
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odRedraw(vn, hmin, vmin, hmax, vmax) /* redraw view region */ |
| 267 |
int vn, hmin, vmin, hmax, vmax; |
| 268 |
{ |
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int i, j; |
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register struct ODblock *bp; |
| 271 |
register int k; |
| 272 |
|
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if (vn<0 | vn>=odNViews) |
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return; |
| 275 |
/* check view limits */ |
| 276 |
if (hmin < 0) hmin = 0; |
| 277 |
if (hmax >= odView[vn].hhi) hmax = odView[vn].hhi-1; |
| 278 |
if (vmin < 0) vmin = 0; |
| 279 |
if (vmax >= odView[vn].vhi) vmax = odView[vn].vhi-1; |
| 280 |
if (hmax <= hmin | vmax <= vmin) |
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return; |
| 282 |
/* convert to low resolution */ |
| 283 |
hmin = hmin * odView[vn].hlow / odView[vn].hhi; |
| 284 |
hmax = hmax * odView[vn].hlow / odView[vn].hhi; |
| 285 |
vmin = vmin * odView[vn].vlow / odView[vn].vhi; |
| 286 |
vmax = vmax * odView[vn].vlow / odView[vn].vhi; |
| 287 |
/* mark block samples for redraw, inclusive */ |
| 288 |
for (i = hmin; i <= hmax; i++) |
| 289 |
for (j = vmin; j <= vmax; j++) { |
| 290 |
bp = odView[vn].bmap + j*odView[vn].hlow + i; |
| 291 |
for (k = bp->nsamp; k--; ) |
| 292 |
if (odS.ip[bp->first+k][0] >= 0) |
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SET4(odS.redraw, bp->first+k); |
| 294 |
} |
| 295 |
} |
| 296 |
|
| 297 |
|
| 298 |
odDepthMap(vn, dm) /* assign depth map for view */ |
| 299 |
int vn; |
| 300 |
GLfloat *dm; |
| 301 |
{ |
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double d0, d1; |
| 303 |
int i, j, hmin, hmax, vmin, vmax; |
| 304 |
register int k, l; |
| 305 |
|
| 306 |
DCHECK(vn<0 | vn>=odNViews, CONSISTENCY, |
| 307 |
"bad view number in odDepthMap"); |
| 308 |
if (dm == NULL) { /* free edge map */ |
| 309 |
if (odView[vn].emap != NULL) |
| 310 |
free((char *)odView[vn].emap); |
| 311 |
odView[vn].emap = NULL; |
| 312 |
odView[vn].dmap = NULL; |
| 313 |
return; |
| 314 |
} |
| 315 |
odView[vn].dmap = dm; /* initialize edge map */ |
| 316 |
if (odView[vn].emap == NULL) { |
| 317 |
odView[vn].emap = (int4 *)malloc( |
| 318 |
FL4NELS(odView[vn].hlow*odView[vn].vlow)*sizeof(int4)); |
| 319 |
if (odView[vn].emap == NULL) |
| 320 |
error(SYSTEM, "out of memory in odDepthMap"); |
| 321 |
} |
| 322 |
CLR4ALL(odView[vn].emap, odView[vn].hlow*odView[vn].vlow); |
| 323 |
/* compute edge map */ |
| 324 |
vmin = odView[vn].vhi; /* enter loopsville */ |
| 325 |
for (j = odView[vn].vlow; j--; ) { |
| 326 |
vmax = vmin; |
| 327 |
vmin = j*odView[vn].vhi/odView[vn].vlow; |
| 328 |
hmin = odView[vn].hhi; |
| 329 |
for (i = odView[vn].hlow; i--; ) { |
| 330 |
hmax = hmin; |
| 331 |
hmin = i*odView[vn].hhi/odView[vn].hlow; |
| 332 |
for (l = vmin; l < vmax; l++) { /* vertical edges */ |
| 333 |
d1 = dm[l*odView[vn].hhi+hmin]; |
| 334 |
for (k = hmin+1; k < hmax; k++) { |
| 335 |
d0 = d1; |
| 336 |
d1 = dm[l*odView[vn].hhi+k]; |
| 337 |
if (d0 > (1.+DEPTHEPS)*d1 || |
| 338 |
(1.+DEPTHEPS)*d0 < d1) { |
| 339 |
SET4(odView[vn].emap, |
| 340 |
j*odView[vn].hlow + i); |
| 341 |
break; |
| 342 |
} |
| 343 |
} |
| 344 |
if (k < hmax) |
| 345 |
break; |
| 346 |
} |
| 347 |
if (l < vmax) |
| 348 |
continue; |
| 349 |
for (k = hmin; k < hmax; k++) { /* horizontal edges */ |
| 350 |
d1 = dm[vmin*odView[vn].hhi+k]; |
| 351 |
for (l = vmin+1; l < vmax; l++) { |
| 352 |
d0 = d1; |
| 353 |
d1 = dm[l*odView[vn].hhi+k]; |
| 354 |
if (d0 > (1.+DEPTHEPS)*d1 || |
| 355 |
(1.+DEPTHEPS)*d0 < d1) { |
| 356 |
SET4(odView[vn].emap, |
| 357 |
j*odView[vn].hlow + i); |
| 358 |
break; |
| 359 |
} |
| 360 |
} |
| 361 |
if (l < vmax) |
| 362 |
break; |
| 363 |
} |
| 364 |
} |
| 365 |
} |
| 366 |
} |
| 367 |
|
| 368 |
|
| 369 |
odUpdate(vn) /* update this view */ |
| 370 |
int vn; |
| 371 |
{ |
| 372 |
int i, j; |
| 373 |
register struct ODblock *bp; |
| 374 |
register int k; |
| 375 |
|
| 376 |
DCHECK(vn<0 | vn>=odNViews, CONSISTENCY, |
| 377 |
"bad view number in odUpdate"); |
| 378 |
/* need to do some tone mapping? */ |
| 379 |
if (needmapping & NEWRGB) { |
| 380 |
if (needmapping & NEWMAP) { |
| 381 |
tmClearHisto(); |
| 382 |
if (tmAddHisto(odS.brt,odS.nsamp,1) != TM_E_OK) |
| 383 |
return; |
| 384 |
if (tmComputeMapping(0.,0.,0.) != TM_E_OK) |
| 385 |
return; |
| 386 |
for (k = odS.nsamp; k--; ) /* redraw all */ |
| 387 |
if (odS.ip[k][0] >= 0) |
| 388 |
SET4(odS.redraw, k); |
| 389 |
} |
| 390 |
if (tmMapPixels(odS.rgb,odS.brt,odS.chr,odS.nsamp) != TM_E_OK) |
| 391 |
return; |
| 392 |
needmapping = 0; /* reset flag */ |
| 393 |
} |
| 394 |
/* draw each block in view */ |
| 395 |
for (i = odView[vn].hlow; i--; ) |
| 396 |
for (j = odView[vn].vlow; j--; ) { |
| 397 |
/* get block */ |
| 398 |
bp = odView[vn].bmap + j*odView[vn].hlow + i; |
| 399 |
/* do quick, conservative flag check */ |
| 400 |
for (k = (bp->first+bp->nsamp+31)>>5; |
| 401 |
k-- > bp->first>>5; ) |
| 402 |
if (odS.redraw[k]) |
| 403 |
break; /* non-zero flag */ |
| 404 |
if (k < bp->first>>5) |
| 405 |
continue; /* no flags set */ |
| 406 |
for (k = bp->nsamp; k--; ) /* sample by sample */ |
| 407 |
if (CHK4(odS.redraw, bp->first+k)) { |
| 408 |
odDrawBlockSamp(vn, i, j, bp->first+k); |
| 409 |
CLR4(odS.redraw, bp->first+k); |
| 410 |
} |
| 411 |
} |
| 412 |
} |
| 413 |
|
| 414 |
|
| 415 |
#if 0 |
| 416 |
static |
| 417 |
clip_end(p, o, vp) /* clip line segment to view */ |
| 418 |
GLshort p[3]; |
| 419 |
short o[2]; |
| 420 |
register struct ODview *vp; |
| 421 |
{ |
| 422 |
if (p[0] < 0) { |
| 423 |
p[1] = -o[0]*(p[1]-o[1])/(p[0]-o[0]) + o[1]; |
| 424 |
p[2] = -o[0]*p[2]/(p[0]-o[0]); |
| 425 |
p[0] = 0; |
| 426 |
} else if (p[0] >= vp->hhi) { |
| 427 |
p[1] = (vp->hhi-1-o[0])*(p[1]-o[1])/(p[0]-o[0]) + o[1]; |
| 428 |
p[2] = (vp->hhi-1-o[0])*p[2]/(p[0]-o[0]); |
| 429 |
p[0] = vp->hhi-1; |
| 430 |
} |
| 431 |
if (p[1] < 0) { |
| 432 |
p[0] = -o[1]*(p[0]-o[0])/(p[1]-o[1]) + o[0]; |
| 433 |
p[2] = -o[1]*p[2]/(p[1]-o[1]); |
| 434 |
p[1] = 0; |
| 435 |
} else if (p[1] >= vp->vhi) { |
| 436 |
p[0] = (vp->vhi-1-o[1])*(p[0]-o[0])/(p[1]-o[1]) + o[0]; |
| 437 |
p[2] = (vp->vhi-1-o[1])*p[2]/(p[1]-o[1]); |
| 438 |
p[1] = vp->vhi-1; |
| 439 |
} |
| 440 |
} |
| 441 |
#endif |
| 442 |
|
| 443 |
|
| 444 |
static int |
| 445 |
make_arms(ar, cp, vp, sz) /* make arms for triangle fan */ |
| 446 |
GLshort ar[MAXFAN][3]; |
| 447 |
short cp[2]; |
| 448 |
register struct ODview *vp; |
| 449 |
double sz; |
| 450 |
{ |
| 451 |
int na, dv; |
| 452 |
double hrad, vrad, phi0, phi; |
| 453 |
register int i; |
| 454 |
|
| 455 |
DCHECK(sz > 1, CONSISTENCY, "super-unary size in make_arms"); |
| 456 |
na = MAXFAN*sz*sz + 0.5; /* keep area constant */ |
| 457 |
if (na < MINFAN) na = MINFAN; |
| 458 |
hrad = FANSIZE*sz*vp->hhi/vp->hlow; |
| 459 |
vrad = FANSIZE*sz*vp->vhi/vp->vlow; |
| 460 |
if (hrad*vrad < 2.25) |
| 461 |
hrad = vrad = 1.5; |
| 462 |
phi0 = (2.*PI) * frandom(); |
| 463 |
dv = OMAXDEPTH*sz + 0.5; |
| 464 |
for (i = 0; i < na; i++) { |
| 465 |
phi = phi0 + (2.*PI)*i/na; |
| 466 |
ar[i][0] = cp[0] + tcos(phi)*hrad + 0.5; |
| 467 |
ar[i][1] = cp[1] + tsin(phi)*vrad + 0.5; |
| 468 |
ar[i][2] = dv; |
| 469 |
/* clip_end(ar[i], cp, vp); */ |
| 470 |
} |
| 471 |
return(na); |
| 472 |
} |
| 473 |
|
| 474 |
|
| 475 |
static int |
| 476 |
depthchange(vp, x0, y0, x1, y1) /* check depth discontinuity */ |
| 477 |
register struct ODview *vp; |
| 478 |
int x0, y0, x1, y1; |
| 479 |
{ |
| 480 |
register double d0, d1; |
| 481 |
|
| 482 |
DCHECK(x0<0 | x0>=vp->hhi | y0<0 | y0>=vp->vhi, |
| 483 |
CONSISTENCY, "coordinates off view in depthchange"); |
| 484 |
|
| 485 |
if (x1<0 | x1>=vp->hhi | y1<0 | y1>=vp->vhi) |
| 486 |
return(1); |
| 487 |
|
| 488 |
d0 = vp->dmap[y0*vp->hhi + x0]; |
| 489 |
d1 = vp->dmap[y1*vp->hhi + x1]; |
| 490 |
|
| 491 |
return((1.+DEPTHEPS)*d0 < d1 || d0 > (1.+DEPTHEPS)*d1); |
| 492 |
} |
| 493 |
|
| 494 |
|
| 495 |
static |
| 496 |
clip_edge(p, o, vp) /* clip line segment to depth edge */ |
| 497 |
GLshort p[3]; |
| 498 |
short o[2]; |
| 499 |
register struct ODview *vp; |
| 500 |
{ |
| 501 |
int x, y, xstep, ystep, rise, rise2, run, run2, n; |
| 502 |
|
| 503 |
DCHECK(vp->dmap==NULL, CONSISTENCY, |
| 504 |
"clip_edge called with no depth map"); |
| 505 |
x = o[0]; y = o[1]; |
| 506 |
run = p[0] - x; |
| 507 |
xstep = run > 0 ? 1 : -1; |
| 508 |
run *= xstep; |
| 509 |
rise = p[1] - y; |
| 510 |
ystep = rise > 0 ? 1 : -1; |
| 511 |
rise *= ystep; |
| 512 |
rise2 = run2 = 0; |
| 513 |
if (rise > run) rise2 = 1; |
| 514 |
else run2 = 1; |
| 515 |
n = rise + run; |
| 516 |
while (n--) /* run out arm, checking depth */ |
| 517 |
if (run2 > rise2) { |
| 518 |
if (depthchange(vp, x, y, x+xstep, y)) |
| 519 |
break; |
| 520 |
x += xstep; |
| 521 |
rise2 += rise; |
| 522 |
} else { |
| 523 |
if (depthchange(vp, x, y, x, y+ystep)) |
| 524 |
break; |
| 525 |
y += ystep; |
| 526 |
run2 += run; |
| 527 |
} |
| 528 |
if (n < 0) /* found something? */ |
| 529 |
return; |
| 530 |
if (run > rise) |
| 531 |
p[2] = (x - o[0])*p[2]/(p[0] - o[0]); |
| 532 |
else |
| 533 |
p[2] = (y - o[1])*p[2]/(p[1] - o[1]); |
| 534 |
p[0] = x; |
| 535 |
p[1] = y; |
| 536 |
} |
| 537 |
|
| 538 |
|
| 539 |
static int |
| 540 |
getblock(vp, h, v) /* get block index */ |
| 541 |
register struct ODview *vp; |
| 542 |
register int h, v; |
| 543 |
{ |
| 544 |
if (h<0 | h>=vp->hhi | v<0 | v>=vp->vhi) |
| 545 |
return(-1); |
| 546 |
return(h*vp->hlow/vp->hhi + v*vp->vlow/vp->vhi*vp->hlow); |
| 547 |
} |
| 548 |
|
| 549 |
|
| 550 |
odDrawBlockSamp(vn, h, v, id) /* draw sample in view block */ |
| 551 |
int vn, h, v; |
| 552 |
register int id; |
| 553 |
{ |
| 554 |
GLshort arm[MAXFAN][3]; |
| 555 |
int narms, blockindex, bi1; |
| 556 |
register struct ODview *vp; |
| 557 |
double size; |
| 558 |
int home_edges; |
| 559 |
register int i; |
| 560 |
|
| 561 |
vp = odView + vn; |
| 562 |
blockindex = v*vp->hlow + h; |
| 563 |
DCHECK(odS.ip[id][0]*vp->hlow/vp->hhi != h | |
| 564 |
odS.ip[id][1]*vp->vlow/vp->vhi != v, |
| 565 |
CONSISTENCY, "bad sample position in odDrawBlockSamp"); |
| 566 |
DCHECK(vp->bmap[blockindex].nused <= 0, |
| 567 |
CONSISTENCY, "bad in-use count in odDrawBlockSamp"); |
| 568 |
/* create triangle fan */ |
| 569 |
size = 1./sqrt((double)vp->bmap[blockindex].nused); |
| 570 |
narms = make_arms(arm, odS.ip[id], vp, size); |
| 571 |
if (vp->emap != NULL) { /* check for edge collisions */ |
| 572 |
home_edges = CHK4(vp->emap, blockindex); |
| 573 |
for (i = 0; i < narms; i++) |
| 574 |
/* the following test is flawed, because we could |
| 575 |
* be passing through a block on a diagonal run */ |
| 576 |
if (home_edges || |
| 577 |
( (bi1 = getblock(vp, arm[i][0], arm[i][1])) |
| 578 |
!= blockindex && |
| 579 |
(bi1 < 0 || CHK4(vp->emap, bi1)) )) |
| 580 |
clip_edge(arm[i], odS.ip[id], vp); |
| 581 |
} |
| 582 |
/* draw triangle fan */ |
| 583 |
glColor3ub(odS.rgb[id][0], odS.rgb[id][1], odS.rgb[id][2]); |
| 584 |
glBegin(GL_TRIANGLE_FAN); |
| 585 |
glVertex3s((GLshort)odS.ip[id][0], (GLshort)odS.ip[id][1], (GLshort)0); |
| 586 |
for (i = 0; i < narms; i++) |
| 587 |
glVertex3sv(arm[i]); |
| 588 |
glVertex3sv(arm[0]); /* connect last to first */ |
| 589 |
glEnd(); |
| 590 |
} |
