1 |
#ifndef lint |
2 |
static const char RCSid[] = "$Id$"; |
3 |
#endif |
4 |
/* |
5 |
* Radiance triangle mesh conversion routines |
6 |
*/ |
7 |
|
8 |
#include "copyright.h" |
9 |
#include "standard.h" |
10 |
#include "cvmesh.h" |
11 |
#include "otypes.h" |
12 |
#include "face.h" |
13 |
|
14 |
/* |
15 |
* We need to divide faces into triangles and record auxiliary information |
16 |
* if given (surface normal and uv coordinates). We do this by extending |
17 |
* the face structure linked to the OBJREC os member and putting our |
18 |
* auxiliary after it -- a bit sly, but it works. |
19 |
*/ |
20 |
|
21 |
/* Auxiliary data for triangle */ |
22 |
typedef struct { |
23 |
int fl; /* flags of what we're storing */ |
24 |
OBJECT obj; /* mesh triangle ID */ |
25 |
FVECT vn[3]; /* normals */ |
26 |
FLOAT vc[3][2]; /* uv coords. */ |
27 |
} TRIDATA; |
28 |
|
29 |
#define tdsize(fl) ((fl)&MT_UV ? sizeof(TRIDATA) : \ |
30 |
(fl)&MT_N ? sizeof(TRIDATA)-2*sizeof(FLOAT) : \ |
31 |
sizeof(int)+sizeof(OBJECT)) |
32 |
|
33 |
#define OMARGIN (10*FTINY) /* margin around global cube */ |
34 |
|
35 |
MESH *ourmesh = NULL; /* our global mesh data structure */ |
36 |
|
37 |
FVECT meshbounds[2]; /* mesh bounding box */ |
38 |
|
39 |
|
40 |
MESH * |
41 |
cvinit(nm) /* initialize empty mesh */ |
42 |
char *nm; |
43 |
{ |
44 |
/* free old mesh, first */ |
45 |
if (ourmesh != NULL) { |
46 |
freemesh(ourmesh); |
47 |
ourmesh = NULL; |
48 |
freeobjects(0, nobjects); |
49 |
donesets(); |
50 |
} |
51 |
if (nm == NULL) |
52 |
return(NULL); |
53 |
ourmesh = (MESH *)calloc(1, sizeof(MESH)); |
54 |
if (ourmesh == NULL) |
55 |
goto nomem; |
56 |
ourmesh->name = savestr(nm); |
57 |
ourmesh->nref = 1; |
58 |
ourmesh->ldflags = 0; |
59 |
ourmesh->mcube.cutree = EMPTY; |
60 |
ourmesh->uvlim[0][0] = ourmesh->uvlim[1][0] = FHUGE; |
61 |
ourmesh->uvlim[0][1] = ourmesh->uvlim[1][1] = -FHUGE; |
62 |
meshbounds[0][0] = meshbounds[0][1] = meshbounds[0][2] = FHUGE; |
63 |
meshbounds[1][0] = meshbounds[1][1] = meshbounds[1][2] = -FHUGE; |
64 |
return(ourmesh); |
65 |
nomem: |
66 |
error(SYSTEM, "out of memory in cvinit"); |
67 |
return(NULL); |
68 |
} |
69 |
|
70 |
|
71 |
int |
72 |
cvpoly(n, vp, vn, vc) /* convert a polygon to extended triangles */ |
73 |
int n; |
74 |
FVECT *vp; |
75 |
FVECT *vn; |
76 |
FLOAT (*vc)[2]; |
77 |
{ |
78 |
int tcnt = 0; |
79 |
int flags; |
80 |
FLOAT *tn[3], *tc[3]; |
81 |
int *ord; |
82 |
int i, j; |
83 |
|
84 |
if (n < 3) /* degenerate face */ |
85 |
return(0); |
86 |
flags = MT_V; |
87 |
if (vn != NULL) { |
88 |
tn[0] = vn[0]; tn[1] = vn[1]; tn[2] = vn[2]; |
89 |
flags |= MT_N; |
90 |
} else { |
91 |
tn[0] = tn[1] = tn[2] = NULL; |
92 |
} |
93 |
if (vc != NULL) { |
94 |
tc[0] = vc[0]; tc[1] = vc[1]; tc[2] = vc[2]; |
95 |
flags |= MT_UV; |
96 |
} else { |
97 |
tc[0] = tc[1] = tc[2] = NULL; |
98 |
} |
99 |
if (n == 3) /* output single triangle */ |
100 |
return(cvtri(vp[0], vp[1], vp[2], |
101 |
tn[0], tn[1], tn[2], |
102 |
tc[0], tc[1], tc[2])); |
103 |
|
104 |
/* decimate polygon (assumes convex) */ |
105 |
ord = (int *)malloc(n*sizeof(int)); |
106 |
if (ord == NULL) |
107 |
error(SYSTEM, "out of memory in cvpoly"); |
108 |
for (i = n; i--; ) |
109 |
ord[i] = i; |
110 |
while (n >= 3) { |
111 |
if (flags & MT_N) |
112 |
for (i = 3; i--; ) |
113 |
tn[i] = vn[ord[i]]; |
114 |
if (flags & MT_UV) |
115 |
for (i = 3; i--; ) |
116 |
tc[i] = vc[ord[i]]; |
117 |
i = cvtri(vp[ord[0]], vp[ord[1]], vp[ord[2]], |
118 |
tn[0], tn[1], tn[2], |
119 |
tc[0], tc[1], tc[2]); |
120 |
if (i < 0) |
121 |
return(i); |
122 |
tcnt += i; |
123 |
/* remove vertex and rotate */ |
124 |
n--; |
125 |
j = ord[0]; |
126 |
for (i = 0; i < n-1; i++) |
127 |
ord[i] = ord[i+2]; |
128 |
ord[i] = j; |
129 |
} |
130 |
free((void *)ord); |
131 |
return(tcnt); |
132 |
} |
133 |
|
134 |
|
135 |
static void |
136 |
add2bounds(vp, vc) /* add point and uv coordinate to bounds */ |
137 |
FVECT vp; |
138 |
FLOAT vc[2]; |
139 |
{ |
140 |
register int j; |
141 |
|
142 |
for (j = 3; j--; ) { |
143 |
if (vp[j] < meshbounds[0][j]) |
144 |
meshbounds[0][j] = vp[j]; |
145 |
if (vp[j] > meshbounds[1][j]) |
146 |
meshbounds[1][j] = vp[j]; |
147 |
} |
148 |
if (vc == NULL) |
149 |
return; |
150 |
for (j = 2; j--; ) { |
151 |
if (vc[j] < ourmesh->uvlim[0][j]) |
152 |
ourmesh->uvlim[0][j] = vc[j]; |
153 |
if (vc[j] > ourmesh->uvlim[1][j]) |
154 |
ourmesh->uvlim[1][j] = vc[j]; |
155 |
} |
156 |
} |
157 |
|
158 |
|
159 |
int /* create an extended triangle */ |
160 |
cvtri(vp1, vp2, vp3, vn1, vn2, vn3, vc1, vc2, vc3) |
161 |
FVECT vp1, vp2, vp3; |
162 |
FVECT vn1, vn2, vn3; |
163 |
FLOAT vc1[2], vc2[2], vc3[2]; |
164 |
{ |
165 |
char buf[32]; |
166 |
int flags; |
167 |
TRIDATA *ts; |
168 |
OBJECT fobj; |
169 |
FACE *f; |
170 |
OBJREC *fop; |
171 |
int j; |
172 |
|
173 |
flags = MT_V; |
174 |
if (vn1 != NULL && vn2 != NULL && vn3 != NULL) |
175 |
flags |= MT_N; |
176 |
if (vc1 != NULL && vc2 != NULL && vc3 != NULL) |
177 |
flags |= MT_UV; |
178 |
/* create extended triangle */ |
179 |
fobj = newobject(); |
180 |
if (fobj == OVOID) |
181 |
return(-1); |
182 |
fop = objptr(fobj); |
183 |
fop->omod = OVOID; |
184 |
fop->otype = OBJ_FACE; |
185 |
sprintf(buf, "t%d", fobj); |
186 |
fop->oname = savqstr(buf); |
187 |
fop->oargs.nfargs = 9; |
188 |
fop->oargs.farg = (FLOAT *)malloc(9*sizeof(FLOAT)); |
189 |
if (fop->oargs.farg == NULL) |
190 |
goto nomem; |
191 |
for (j = 3; j--; ) { |
192 |
fop->oargs.farg[j] = vp1[j]; |
193 |
fop->oargs.farg[3+j] = vp2[j]; |
194 |
fop->oargs.farg[6+j] = vp3[j]; |
195 |
} |
196 |
/* create face record */ |
197 |
if ((f = getface(fop)) == NULL || f->area == 0.) { |
198 |
freeobjects(fobj, 1); |
199 |
return(0); |
200 |
} |
201 |
if (fop->os != (char *)f) |
202 |
error(CONSISTENCY, "code error in cvtri"); |
203 |
/* follow with auxliary data */ |
204 |
f = (FACE *)realloc((void *)f, sizeof(FACE)+tdsize(flags)); |
205 |
if (f == NULL) |
206 |
goto nomem; |
207 |
fop->os = (char *)f; |
208 |
ts = (TRIDATA *)(f+1); |
209 |
ts->fl = flags; |
210 |
ts->obj = OVOID; |
211 |
if (flags & MT_N) |
212 |
for (j = 3; j--; ) { |
213 |
ts->vn[0][j] = vn1[j]; |
214 |
ts->vn[1][j] = vn2[j]; |
215 |
ts->vn[2][j] = vn3[j]; |
216 |
} |
217 |
if (flags & MT_UV) |
218 |
for (j = 2; j--; ) { |
219 |
ts->vc[0][j] = vc1[j]; |
220 |
ts->vc[1][j] = vc2[j]; |
221 |
ts->vc[2][j] = vc3[j]; |
222 |
} |
223 |
else |
224 |
vc1 = vc2 = vc3 = NULL; |
225 |
/* update bounds */ |
226 |
add2bounds(vp1, vc1); |
227 |
add2bounds(vp2, vc2); |
228 |
add2bounds(vp3, vc3); |
229 |
return(1); |
230 |
nomem: |
231 |
error(SYSTEM, "out of memory in cvtri"); |
232 |
return(0); |
233 |
} |
234 |
|
235 |
|
236 |
static OBJECT |
237 |
cvmeshtri(obj) /* add an extended triangle to our mesh */ |
238 |
OBJECT obj; |
239 |
{ |
240 |
OBJREC *o = objptr(obj); |
241 |
TRIDATA *ts; |
242 |
MESHVERT vert[3]; |
243 |
int i, j; |
244 |
|
245 |
if (o->otype != OBJ_FACE) |
246 |
error(CONSISTENCY, "non-face in mesh"); |
247 |
if (o->oargs.nfargs != 9) |
248 |
error(CONSISTENCY, "non-triangle in mesh"); |
249 |
if (o->os == NULL) |
250 |
error(CONSISTENCY, "missing face record in cvmeshtri"); |
251 |
ts = (TRIDATA *)((FACE *)o->os + 1); |
252 |
if (ts->obj != OVOID) /* already added? */ |
253 |
return(ts->obj); |
254 |
vert[0].fl = vert[1].fl = vert[2].fl = ts->fl; |
255 |
for (i = 3; i--; ) |
256 |
for (j = 3; j--; ) |
257 |
vert[i].v[j] = o->oargs.farg[3*i+j]; |
258 |
if (ts->fl & MT_N) |
259 |
for (i = 3; i--; ) |
260 |
for (j = 3; j--; ) |
261 |
vert[i].n[j] = ts->vn[i][j]; |
262 |
if (ts->fl & MT_UV) |
263 |
for (i = 3; i--; ) |
264 |
for (j = 2; j--; ) |
265 |
vert[i].uv[j] = ts->vc[i][j]; |
266 |
ts->obj = addmeshtri(ourmesh, vert); |
267 |
if (ts->obj == OVOID) |
268 |
error(INTERNAL, "addmeshtri failed"); |
269 |
return(ts->obj); |
270 |
} |
271 |
|
272 |
|
273 |
void |
274 |
cvmeshbounds() /* set mesh boundaries */ |
275 |
{ |
276 |
int i; |
277 |
|
278 |
if (ourmesh == NULL) |
279 |
return; |
280 |
/* fix coordinate bounds */ |
281 |
for (i = 0; i < 3; i++) { |
282 |
if (meshbounds[0][i] >= meshbounds[1][i]) |
283 |
error(USER, "no polygons in mesh"); |
284 |
meshbounds[0][i] -= OMARGIN; |
285 |
meshbounds[1][i] += OMARGIN; |
286 |
if (meshbounds[1][i]-meshbounds[0][i] > ourmesh->mcube.cusize) |
287 |
ourmesh->mcube.cusize = meshbounds[1][i] - |
288 |
meshbounds[0][i]; |
289 |
} |
290 |
for (i = 0; i < 3; i++) |
291 |
ourmesh->mcube.cuorg[i] = (meshbounds[1][i]+meshbounds[0][i] - |
292 |
ourmesh->mcube.cusize)*.5; |
293 |
if (ourmesh->uvlim[0][0] >= ourmesh->uvlim[1][0]) { |
294 |
ourmesh->uvlim[0][0] = ourmesh->uvlim[0][1] = 0.; |
295 |
ourmesh->uvlim[1][0] = ourmesh->uvlim[1][1] = 0.; |
296 |
} else { |
297 |
for (i = 0; i < 2; i++) { |
298 |
double marg; |
299 |
marg = 1e-6*(ourmesh->uvlim[1][i] - |
300 |
ourmesh->uvlim[0][i]); |
301 |
ourmesh->uvlim[0][i] -= marg; |
302 |
ourmesh->uvlim[1][i] += marg; |
303 |
} |
304 |
} |
305 |
ourmesh->ldflags |= IO_BOUNDS; |
306 |
} |
307 |
|
308 |
|
309 |
static OCTREE |
310 |
cvmeshoct(ot) /* convert triangles in subtree */ |
311 |
OCTREE ot; |
312 |
{ |
313 |
int i; |
314 |
|
315 |
if (isempty(ot)) |
316 |
return(EMPTY); |
317 |
|
318 |
if (isfull(ot)) { |
319 |
OBJECT oset1[MAXSET+1]; |
320 |
OBJECT oset2[MAXSET+1]; |
321 |
objset(oset1, ot); |
322 |
oset2[0] = 0; |
323 |
for (i = oset1[0]; i > 0; i--) |
324 |
insertelem(oset2, cvmeshtri(oset1[i])); |
325 |
return(fullnode(oset2)); |
326 |
} |
327 |
|
328 |
for (i = 8; i--; ) |
329 |
octkid(ot, i) = cvmeshoct(octkid(ot, i)); |
330 |
return(ot); |
331 |
} |
332 |
|
333 |
|
334 |
MESH * |
335 |
cvmesh() /* convert mesh and octree leaf nodes */ |
336 |
{ |
337 |
if (ourmesh == NULL) |
338 |
return(NULL); |
339 |
/* convert triangles in octree nodes */ |
340 |
ourmesh->mcube.cutree = cvmeshoct(ourmesh->mcube.cutree); |
341 |
ourmesh->ldflags |= IO_SCENE|IO_TREE; |
342 |
|
343 |
return(ourmesh); |
344 |
} |