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#ifndef lint |
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static const char RCSid[] = "$Id: cvmesh.c,v 2.9 2004/03/27 12:41:45 schorsch Exp $"; |
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#endif |
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/* |
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* Radiance triangle mesh conversion routines |
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*/ |
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|
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#include "copyright.h" |
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#include "standard.h" |
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#include "cvmesh.h" |
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#include "otypes.h" |
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#include "face.h" |
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#include "tmesh.h" |
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|
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/* |
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* We need to divide faces into triangles and record auxiliary information |
| 17 |
* if given (surface normal and uv coordinates). We do this by extending |
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* the face structure linked to the OBJREC os member and putting our |
| 19 |
* auxiliary after it -- a bit sly, but it works. |
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*/ |
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|
| 22 |
/* Auxiliary data for triangle */ |
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typedef struct { |
| 24 |
int fl; /* flags of what we're storing */ |
| 25 |
OBJECT obj; /* mesh triangle ID */ |
| 26 |
FVECT vn[3]; /* normals */ |
| 27 |
RREAL vc[3][2]; /* uv coords. */ |
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} TRIDATA; |
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|
| 30 |
#define tdsize(fl) ((fl)&MT_UV ? sizeof(TRIDATA) : \ |
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(fl)&MT_N ? sizeof(TRIDATA)-6*sizeof(RREAL) : \ |
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sizeof(int)+sizeof(OBJECT)) |
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|
| 34 |
#define OMARGIN (10*FTINY) /* margin around global cube */ |
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|
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MESH *ourmesh = NULL; /* our global mesh data structure */ |
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|
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FVECT meshbounds[2]; /* mesh bounding box */ |
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|
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static void add2bounds(FVECT vp, RREAL vc[2]); |
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static OBJECT cvmeshtri(OBJECT obj); |
| 42 |
static OCTREE cvmeshoct(OCTREE ot); |
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|
| 44 |
|
| 45 |
|
| 46 |
MESH * |
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cvinit( /* initialize empty mesh */ |
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char *nm |
| 49 |
) |
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{ |
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/* free old mesh, first */ |
| 52 |
if (ourmesh != NULL) { |
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freemesh(ourmesh); |
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ourmesh = NULL; |
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freeobjects(0, nobjects); |
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donesets(); |
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} |
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if (nm == NULL) |
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return(NULL); |
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ourmesh = (MESH *)calloc(1, sizeof(MESH)); |
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if (ourmesh == NULL) |
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goto nomem; |
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ourmesh->name = savestr(nm); |
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ourmesh->nref = 1; |
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ourmesh->ldflags = 0; |
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ourmesh->mcube.cutree = EMPTY; |
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ourmesh->uvlim[0][0] = ourmesh->uvlim[0][1] = FHUGE; |
| 68 |
ourmesh->uvlim[1][0] = ourmesh->uvlim[1][1] = -FHUGE; |
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meshbounds[0][0] = meshbounds[0][1] = meshbounds[0][2] = FHUGE; |
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meshbounds[1][0] = meshbounds[1][1] = meshbounds[1][2] = -FHUGE; |
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return(ourmesh); |
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nomem: |
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error(SYSTEM, "out of memory in cvinit"); |
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return(NULL); |
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} |
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|
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|
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int |
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cvpoly( /* convert a polygon to extended triangles */ |
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OBJECT mo, |
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int n, |
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FVECT *vp, |
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FVECT *vn, |
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RREAL (*vc)[2] |
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) |
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{ |
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int tcnt = 0; |
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int flags; |
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RREAL *tn[3], *tc[3]; |
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int *ord; |
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int i, j; |
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|
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if (n < 3) /* degenerate face */ |
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return(0); |
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flags = MT_V; |
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if (vn != NULL) { |
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tn[0] = vn[0]; tn[1] = vn[1]; tn[2] = vn[2]; |
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flags |= MT_N; |
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} else { |
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tn[0] = tn[1] = tn[2] = NULL; |
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} |
| 102 |
if (vc != NULL) { |
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tc[0] = vc[0]; tc[1] = vc[1]; tc[2] = vc[2]; |
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flags |= MT_UV; |
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} else { |
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tc[0] = tc[1] = tc[2] = NULL; |
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} |
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if (n == 3) /* output single triangle */ |
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return(cvtri(mo, vp[0], vp[1], vp[2], |
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tn[0], tn[1], tn[2], |
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tc[0], tc[1], tc[2])); |
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|
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/* decimate polygon (assumes convex) */ |
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ord = (int *)malloc(n*sizeof(int)); |
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if (ord == NULL) |
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error(SYSTEM, "out of memory in cvpoly"); |
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for (i = n; i--; ) |
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ord[i] = i; |
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while (n >= 3) { |
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if (flags & MT_N) |
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for (i = 3; i--; ) |
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tn[i] = vn[ord[i]]; |
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if (flags & MT_UV) |
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for (i = 3; i--; ) |
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tc[i] = vc[ord[i]]; |
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tcnt += cvtri(mo, vp[ord[0]], vp[ord[1]], vp[ord[2]], |
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tn[0], tn[1], tn[2], |
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tc[0], tc[1], tc[2]); |
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/* remove vertex and rotate */ |
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n--; |
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j = ord[0]; |
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for (i = 0; i < n-1; i++) |
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ord[i] = ord[i+2]; |
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ord[i] = j; |
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} |
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free((void *)ord); |
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return(tcnt); |
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} |
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|
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|
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static void |
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add2bounds( /* add point and uv coordinate to bounds */ |
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FVECT vp, |
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RREAL vc[2] |
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) |
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{ |
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register int j; |
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|
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for (j = 3; j--; ) { |
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if (vp[j] < meshbounds[0][j]) |
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meshbounds[0][j] = vp[j]; |
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if (vp[j] > meshbounds[1][j]) |
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meshbounds[1][j] = vp[j]; |
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} |
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if (vc == NULL) |
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return; |
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for (j = 2; j--; ) { |
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if (vc[j] < ourmesh->uvlim[0][j]) |
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ourmesh->uvlim[0][j] = vc[j]; |
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if (vc[j] > ourmesh->uvlim[1][j]) |
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ourmesh->uvlim[1][j] = vc[j]; |
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} |
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} |
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|
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|
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int /* create an extended triangle */ |
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cvtri( |
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OBJECT mo, |
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FVECT vp1, |
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FVECT vp2, |
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FVECT vp3, |
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FVECT vn1, |
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FVECT vn2, |
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FVECT vn3, |
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RREAL vc1[2], |
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RREAL vc2[2], |
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RREAL vc3[2] |
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) |
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{ |
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static OBJECT fobj = OVOID; |
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char buf[32]; |
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int flags; |
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TRIDATA *ts; |
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FACE *f; |
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OBJREC *fop; |
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int j; |
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|
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flags = MT_V; /* check what we have */ |
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if (vn1 != NULL && vn2 != NULL && vn3 != NULL) { |
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RREAL *rp; |
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switch (flat_tri(vp1, vp2, vp3, vn1, vn2, vn3)) { |
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case ISBENT: |
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flags |= MT_N; |
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/* fall through */ |
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case ISFLAT: |
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break; |
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case RVBENT: |
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flags |= MT_N; |
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rp = vn1; vn1 = vn3; vn3 = rp; |
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/* fall through */ |
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case RVFLAT: |
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rp = vp1; vp1 = vp3; vp3 = rp; |
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rp = vc1; vc1 = vc3; vc3 = rp; |
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break; |
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case DEGEN: |
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error(WARNING, "degenerate triangle"); |
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return(0); |
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default: |
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error(INTERNAL, "bad return from flat_tri()"); |
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} |
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} |
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if (vc1 != NULL && vc2 != NULL && vc3 != NULL) |
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flags |= MT_UV; |
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if (fobj == OVOID) { /* create new triangle object */ |
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fobj = newobject(); |
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if (fobj == OVOID) |
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goto nomem; |
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fop = objptr(fobj); |
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fop->omod = mo; |
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fop->otype = OBJ_FACE; |
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sprintf(buf, "t%ld", fobj); |
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fop->oname = savqstr(buf); |
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fop->oargs.nfargs = 9; |
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fop->oargs.farg = (RREAL *)malloc(9*sizeof(RREAL)); |
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if (fop->oargs.farg == NULL) |
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goto nomem; |
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} else { /* else reuse failed one */ |
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fop = objptr(fobj); |
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if (fop->otype != OBJ_FACE || fop->oargs.nfargs != 9) |
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error(CONSISTENCY, "code error 1 in cvtri"); |
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} |
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for (j = 3; j--; ) { |
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fop->oargs.farg[j] = vp1[j]; |
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fop->oargs.farg[3+j] = vp2[j]; |
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fop->oargs.farg[6+j] = vp3[j]; |
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} |
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/* create face record */ |
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f = getface(fop); |
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if (f->area == 0.) { |
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free_os(fop); |
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return(0); |
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} |
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if (fop->os != (char *)f) |
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error(CONSISTENCY, "code error 2 in cvtri"); |
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/* follow with auxliary data */ |
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f = (FACE *)realloc((void *)f, sizeof(FACE)+tdsize(flags)); |
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if (f == NULL) |
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goto nomem; |
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fop->os = (char *)f; |
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ts = (TRIDATA *)(f+1); |
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ts->fl = flags; |
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ts->obj = OVOID; |
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if (flags & MT_N) |
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for (j = 3; j--; ) { |
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ts->vn[0][j] = vn1[j]; |
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ts->vn[1][j] = vn2[j]; |
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ts->vn[2][j] = vn3[j]; |
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} |
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if (flags & MT_UV) |
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for (j = 2; j--; ) { |
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ts->vc[0][j] = vc1[j]; |
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ts->vc[1][j] = vc2[j]; |
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ts->vc[2][j] = vc3[j]; |
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} |
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else |
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vc1 = vc2 = vc3 = NULL; |
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/* update bounds */ |
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add2bounds(vp1, vc1); |
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add2bounds(vp2, vc2); |
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add2bounds(vp3, vc3); |
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fobj = OVOID; /* we used this one */ |
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return(1); |
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nomem: |
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error(SYSTEM, "out of memory in cvtri"); |
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return(0); |
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} |
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|
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|
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static OBJECT |
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cvmeshtri( /* add an extended triangle to our mesh */ |
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OBJECT obj |
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) |
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{ |
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OBJREC *o = objptr(obj); |
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TRIDATA *ts; |
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MESHVERT vert[3]; |
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int i, j; |
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|
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if (o->otype != OBJ_FACE) |
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error(CONSISTENCY, "non-face in mesh"); |
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if (o->oargs.nfargs != 9) |
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error(CONSISTENCY, "non-triangle in mesh"); |
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if (o->os == NULL) |
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error(CONSISTENCY, "missing face record in cvmeshtri"); |
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ts = (TRIDATA *)((FACE *)o->os + 1); |
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if (ts->obj != OVOID) /* already added? */ |
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return(ts->obj); |
| 298 |
vert[0].fl = vert[1].fl = vert[2].fl = ts->fl; |
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for (i = 3; i--; ) |
| 300 |
for (j = 3; j--; ) |
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vert[i].v[j] = o->oargs.farg[3*i+j]; |
| 302 |
if (ts->fl & MT_N) |
| 303 |
for (i = 3; i--; ) |
| 304 |
for (j = 3; j--; ) |
| 305 |
vert[i].n[j] = ts->vn[i][j]; |
| 306 |
if (ts->fl & MT_UV) |
| 307 |
for (i = 3; i--; ) |
| 308 |
for (j = 2; j--; ) |
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vert[i].uv[j] = ts->vc[i][j]; |
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ts->obj = addmeshtri(ourmesh, vert, o->omod); |
| 311 |
if (ts->obj == OVOID) |
| 312 |
error(INTERNAL, "addmeshtri failed"); |
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return(ts->obj); |
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} |
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|
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|
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void |
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cvmeshbounds(void) /* set mesh boundaries */ |
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{ |
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int i; |
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|
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if (ourmesh == NULL) |
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return; |
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/* fix coordinate bounds */ |
| 325 |
for (i = 0; i < 3; i++) { |
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if (meshbounds[0][i] > meshbounds[1][i]) |
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error(USER, "no polygons in mesh"); |
| 328 |
meshbounds[0][i] -= OMARGIN; |
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meshbounds[1][i] += OMARGIN; |
| 330 |
if (meshbounds[1][i]-meshbounds[0][i] > ourmesh->mcube.cusize) |
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ourmesh->mcube.cusize = meshbounds[1][i] - |
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meshbounds[0][i]; |
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} |
| 334 |
for (i = 0; i < 3; i++) |
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ourmesh->mcube.cuorg[i] = (meshbounds[1][i]+meshbounds[0][i] - |
| 336 |
ourmesh->mcube.cusize)*.5; |
| 337 |
if (ourmesh->uvlim[0][0] > ourmesh->uvlim[1][0]) { |
| 338 |
ourmesh->uvlim[0][0] = ourmesh->uvlim[0][1] = 0.; |
| 339 |
ourmesh->uvlim[1][0] = ourmesh->uvlim[1][1] = 0.; |
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} else { |
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for (i = 0; i < 2; i++) { |
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double marg; /* expand past endpoints */ |
| 343 |
marg = (2./(1L<<(8*sizeof(uint16)))) * |
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(ourmesh->uvlim[1][i] - |
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ourmesh->uvlim[0][i]) + FTINY; |
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ourmesh->uvlim[0][i] -= marg; |
| 347 |
ourmesh->uvlim[1][i] += marg; |
| 348 |
} |
| 349 |
} |
| 350 |
ourmesh->ldflags |= IO_BOUNDS; |
| 351 |
} |
| 352 |
|
| 353 |
|
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static OCTREE |
| 355 |
cvmeshoct( /* convert triangles in subtree */ |
| 356 |
OCTREE ot |
| 357 |
) |
| 358 |
{ |
| 359 |
int i; |
| 360 |
|
| 361 |
if (isempty(ot)) |
| 362 |
return(EMPTY); |
| 363 |
|
| 364 |
if (isfull(ot)) { |
| 365 |
OBJECT oset1[MAXSET+1]; |
| 366 |
OBJECT oset2[MAXSET+1]; |
| 367 |
objset(oset1, ot); |
| 368 |
oset2[0] = 0; |
| 369 |
for (i = oset1[0]; i > 0; i--) |
| 370 |
insertelem(oset2, cvmeshtri(oset1[i])); |
| 371 |
return(fullnode(oset2)); |
| 372 |
} |
| 373 |
|
| 374 |
for (i = 8; i--; ) |
| 375 |
octkid(ot, i) = cvmeshoct(octkid(ot, i)); |
| 376 |
return(ot); |
| 377 |
} |
| 378 |
|
| 379 |
|
| 380 |
MESH * |
| 381 |
cvmesh(void) /* convert mesh and octree leaf nodes */ |
| 382 |
{ |
| 383 |
if (ourmesh == NULL) |
| 384 |
return(NULL); |
| 385 |
/* convert triangles in octree nodes */ |
| 386 |
ourmesh->mcube.cutree = cvmeshoct(ourmesh->mcube.cutree); |
| 387 |
ourmesh->ldflags |= IO_SCENE|IO_TREE; |
| 388 |
|
| 389 |
return(ourmesh); |
| 390 |
} |
