1 |
/* Copyright (c) 1994 Regents of the University of California */ |
2 |
|
3 |
#ifndef lint |
4 |
static char SCCSid[] = "$SunId$ LBL"; |
5 |
#endif |
6 |
|
7 |
/* |
8 |
* Convert a trianglular mesh into a Radiance description. |
9 |
* |
10 |
* Unlike most other converters, we have defined a file |
11 |
* format for the input ourselves. The format contains eight types, |
12 |
* each of which is identified by a single letter. These are: |
13 |
* |
14 |
* # comment = a comment. Continues until end of line. |
15 |
* v id Px Py Pz = a vertex. The id must be an integer. |
16 |
* n Nx Ny Nz = a normal. Corresponds to most recent vertex. |
17 |
* i Iu Iv = an index. Corresponds to most recent vertex. |
18 |
* p picture = a picture. Used as a pattern for following. |
19 |
* m material = a material name. Used for what follows. |
20 |
* o object = an object name. Used for what follows. |
21 |
* t id1 id2 id3 = a triangle. |
22 |
* |
23 |
* Only the 't' type results in any output. The others merely set values |
24 |
* to be used in generating triangles. If no picture or "p -" is given, |
25 |
* there will be no pattern associated with the geometry. If no material |
26 |
* or "m -" is given, no material will be associated. (Note that this |
27 |
* only makes sense for a mesh which is to be put into an octree for |
28 |
* instancing.) Using a pattern requires that each vertex have an |
29 |
* associated index value for generating the colorpict primitive. |
30 |
* Likewise, an interpolated surface normal also requires that each |
31 |
* vertex of the triangle have an associated normal vector. |
32 |
* It is not necessary for the normal vectors to have unit length. |
33 |
*/ |
34 |
|
35 |
#include "standard.h" |
36 |
|
37 |
#define VOIDID "void" /* this is defined in object.h */ |
38 |
|
39 |
#define CALNAME "tmesh.cal" /* the name of our auxiliary file */ |
40 |
#define PATNAME "T-pat" /* triangle pattern name (reused) */ |
41 |
#define TEXNAME "T-nor" /* triangle texture name (reused) */ |
42 |
|
43 |
#define V_DEFINED 01 /* this vertex is defined */ |
44 |
#define V_HASNORM 02 /* vertex has surface normal */ |
45 |
#define V_HASINDX 04 /* vertex has index */ |
46 |
|
47 |
typedef struct { |
48 |
short flags; /* vertex flags, from above */ |
49 |
FVECT pos; /* location */ |
50 |
FVECT nor; /* normal */ |
51 |
float ndx[2]; /* picture index */ |
52 |
} VERTEX; |
53 |
|
54 |
VERTEX *vlist = NULL; /* our vertex list */ |
55 |
int nverts = 0; /* number of vertices in our list */ |
56 |
|
57 |
typedef FLOAT BARYCCM[3][4]; |
58 |
|
59 |
#define novert(i) ((i)<0|(i)>=nverts || !(vlist[i].flags&V_DEFINED)) |
60 |
|
61 |
#define CHUNKSIZ 128 /* vertex allocation chunk size */ |
62 |
|
63 |
extern VERTEX *vnew(); /* allocate a vertex (never freed) */ |
64 |
|
65 |
char *defmat = VOIDID; /* default (starting) material name */ |
66 |
char *defpat = ""; /* default (starting) picture name */ |
67 |
char *defobj = "T"; /* default (starting) object name */ |
68 |
|
69 |
|
70 |
main(argc, argv) /* read in T-mesh files and convert */ |
71 |
int argc; |
72 |
char *argv[]; |
73 |
{ |
74 |
FILE *fp; |
75 |
int i; |
76 |
|
77 |
for (i = 1; i < argc && argv[i][0] == '-'; i++) |
78 |
switch (argv[i][1]) { |
79 |
case 'o': /* object name */ |
80 |
defobj = argv[++i]; |
81 |
break; |
82 |
case 'm': /* default material */ |
83 |
defmat = argv[++i]; |
84 |
break; |
85 |
case 'p': /* default picture */ |
86 |
defpat = argv[++i]; |
87 |
break; |
88 |
default: |
89 |
fprintf(stderr, |
90 |
"Usage: %s [-o obj][-m mat][-p pic] [file ..]\n", |
91 |
argv[0]); |
92 |
exit(1); |
93 |
} |
94 |
if (i >= argc) |
95 |
convert("<stdin>", stdin); |
96 |
else |
97 |
for ( ; i < argc; i++) { |
98 |
if ((fp = fopen(argv[i], "r")) == NULL) { |
99 |
perror(argv[i]); |
100 |
exit(1); |
101 |
} |
102 |
convert(argv[i], fp); |
103 |
fclose(fp); |
104 |
} |
105 |
exit(0); |
106 |
} |
107 |
|
108 |
|
109 |
convert(fname, fp) /* convert a T-mesh */ |
110 |
char *fname; |
111 |
FILE *fp; |
112 |
{ |
113 |
char typ[4]; |
114 |
int id[3]; |
115 |
double vec[3]; |
116 |
char picfile[128]; |
117 |
char matname[64]; |
118 |
char objname[64]; |
119 |
register int i; |
120 |
register VERTEX *lastv; |
121 |
/* start fresh */ |
122 |
i = nverts; |
123 |
lastv = vlist; |
124 |
while (i--) |
125 |
(lastv++)->flags = 0; |
126 |
lastv = NULL; |
127 |
strcpy(picfile, defpat); |
128 |
strcpy(matname, defmat); |
129 |
strcpy(objname, defobj); |
130 |
|
131 |
printf("\n## T-mesh read from: %s\n", fname); |
132 |
/* scan until EOF */ |
133 |
while (fscanf(fp, "%1s", typ) == 1) |
134 |
switch (typ[0]) { |
135 |
case 'v': /* vertex */ |
136 |
if (fscanf(fp, "%d %lf %lf %lf", &id[0], |
137 |
&vec[0], &vec[1], &vec[2]) != 4) |
138 |
syntax(fname, fp, "Bad vertex"); |
139 |
lastv = vnew(id[0], vec[0], vec[1], vec[2]); |
140 |
break; |
141 |
case 't': /* triangle */ |
142 |
if (fscanf(fp, "%d %d %d", &id[0], &id[1], &id[2]) != 3) |
143 |
syntax(fname, fp, "Bad triangle"); |
144 |
if (novert(id[0]) | novert(id[1]) | novert(id[2])) |
145 |
syntax(fname, fp, "Undefined triangle vertex"); |
146 |
triangle(picfile, matname, objname, &vlist[id[0]], |
147 |
&vlist[id[1]], &vlist[id[2]]); |
148 |
break; |
149 |
case 'n': /* surface normal */ |
150 |
if (lastv == NULL) |
151 |
syntax(fname, fp, "No vertex for normal"); |
152 |
if (fscanf(fp, "%lf %lf %lf", |
153 |
&vec[0], &vec[1], &vec[2]) != 3) |
154 |
syntax(fname, fp, "Bad vertex normal"); |
155 |
lastv->nor[0] = vec[0]; |
156 |
lastv->nor[1] = vec[1]; |
157 |
lastv->nor[2] = vec[2]; |
158 |
if (normalize(lastv->nor) == 0.0) |
159 |
syntax(fname, fp, "Zero vertex normal"); |
160 |
lastv->flags |= V_HASNORM; |
161 |
break; |
162 |
case 'i': /* index position */ |
163 |
if (lastv == NULL) |
164 |
syntax(fname, fp, "No vertex for index"); |
165 |
if (fscanf(fp, "%lf %lf", &vec[0], &vec[1]) != 2) |
166 |
syntax(fname, fp, "Bad index"); |
167 |
lastv->ndx[0] = vec[0]; |
168 |
lastv->ndx[1] = vec[1]; |
169 |
lastv->flags |= V_HASINDX; |
170 |
break; |
171 |
case 'o': /* object name */ |
172 |
if (fscanf(fp, "%s", objname) != 1) |
173 |
syntax(fname, fp, "Bad object name"); |
174 |
break; |
175 |
case 'm': /* material */ |
176 |
if (fscanf(fp, "%s", matname) != 1) |
177 |
syntax(fname, fp, "Bad material"); |
178 |
if (matname[0] == '-' && !matname[1]) |
179 |
strcpy(matname, VOIDID); |
180 |
break; |
181 |
case 'p': /* picture */ |
182 |
if (fscanf(fp, "%s", picfile) != 1) |
183 |
syntax(fname, fp, "Bad pattern"); |
184 |
if (picfile[0] == '-' && !picfile[1]) |
185 |
picfile[0] = '\0'; |
186 |
break; |
187 |
case '#': /* comment */ |
188 |
fputs("\n#", stdout); |
189 |
while ((i = getc(fp)) != EOF) { |
190 |
putchar(i); |
191 |
if (i == '\n') |
192 |
break; |
193 |
} |
194 |
break; |
195 |
default: |
196 |
syntax(fname, fp, "Unknown type"); |
197 |
break; |
198 |
} |
199 |
} |
200 |
|
201 |
|
202 |
triangle(pn, mod, obj, v1, v2, v3) /* put out a triangle */ |
203 |
char *pn, *mod, *obj; |
204 |
register VERTEX *v1, *v2, *v3; |
205 |
{ |
206 |
static int ntri = 0; |
207 |
BARYCCM bvecs; |
208 |
/* compute barycentric coordinates */ |
209 |
if (v1->flags & v2->flags & v3->flags & (V_HASINDX|V_HASNORM)) |
210 |
if (comp_baryc(bvecs, v1->pos, v2->pos, v3->pos) < 0) |
211 |
return; |
212 |
/* put out texture (if any) */ |
213 |
if (v1->flags & v2->flags & v3->flags & V_HASNORM) { |
214 |
printf("\n%s texfunc %s\n", mod, TEXNAME); |
215 |
mod = TEXNAME; |
216 |
printf("4 dx dy dz %s\n", CALNAME); |
217 |
printf("0\n21\n"); |
218 |
put_baryc(bvecs); |
219 |
printf("\t%14.12g %14.12g %14.12g\n", |
220 |
v1->nor[0], v2->nor[0], v3->nor[0]); |
221 |
printf("\t%14.12g %14.12g %14.12g\n", |
222 |
v1->nor[1], v2->nor[1], v3->nor[1]); |
223 |
printf("\t%14.12g %14.12g %14.12g\n", |
224 |
v1->nor[2], v2->nor[2], v3->nor[2]); |
225 |
} |
226 |
/* put out pattern (if any) */ |
227 |
if (*pn && (v1->flags & v2->flags & v3->flags & V_HASINDX)) { |
228 |
printf("\n%s colorpict %s\n", mod, PATNAME); |
229 |
mod = PATNAME; |
230 |
printf("7 noneg noneg noneg %s %s u v\n", pn, CALNAME); |
231 |
printf("0\n18\n"); |
232 |
put_baryc(bvecs); |
233 |
printf("\t%f %f %f\n", v1->ndx[0], v2->ndx[0], v3->ndx[0]); |
234 |
printf("\t%f %f %f\n", v1->ndx[1], v2->ndx[1], v3->ndx[1]); |
235 |
} |
236 |
/* put out triangle */ |
237 |
printf("\n%s polygon %s.%d\n", mod, obj, ++ntri); |
238 |
printf("0\n0\n9\n"); |
239 |
printf("%18.12g %18.12g %18.12g\n", v1->pos[0],v1->pos[1],v1->pos[2]); |
240 |
printf("%18.12g %18.12g %18.12g\n", v2->pos[0],v2->pos[1],v2->pos[2]); |
241 |
printf("%18.12g %18.12g %18.12g\n", v3->pos[0],v3->pos[1],v3->pos[2]); |
242 |
} |
243 |
|
244 |
|
245 |
int |
246 |
comp_baryc(bcm, v1, v2, v3) /* compute barycentric vectors */ |
247 |
register BARYCCM bcm; |
248 |
FLOAT *v1, *v2, *v3; |
249 |
{ |
250 |
FLOAT *vt; |
251 |
FVECT va, vab, vcb; |
252 |
double d; |
253 |
register int i, j; |
254 |
|
255 |
for (j = 0; j < 3; j++) { |
256 |
for (i = 0; i < 3; i++) { |
257 |
vab[i] = v1[i] - v2[i]; |
258 |
vcb[i] = v3[i] - v2[i]; |
259 |
} |
260 |
d = DOT(vcb,vcb); |
261 |
if (d <= FTINY) |
262 |
return(-1); |
263 |
d = DOT(vcb,vab)/d; |
264 |
for (i = 0; i < 3; i++) |
265 |
va[i] = vab[i] - vcb[i]*d; |
266 |
d = DOT(va,va); |
267 |
if (d <= FTINY) |
268 |
return(-1); |
269 |
for (i = 0; i < 3; i++) { |
270 |
va[i] /= d; |
271 |
bcm[j][i] = va[i]; |
272 |
} |
273 |
bcm[j][3] = -DOT(v2,va); |
274 |
/* rotate vertices */ |
275 |
vt = v1; |
276 |
v1 = v2; |
277 |
v2 = v3; |
278 |
v3 = vt; |
279 |
} |
280 |
return(0); |
281 |
} |
282 |
|
283 |
|
284 |
put_baryc(bcm) /* put barycentric coord. vectors */ |
285 |
register BARYCCM bcm; |
286 |
{ |
287 |
register int i; |
288 |
|
289 |
for (i = 0; i < 3; i++) |
290 |
printf("%14.8f %14.8f %14.8f %14.8f\n", |
291 |
bcm[i][0], bcm[i][1], bcm[i][2], bcm[i][3]); |
292 |
} |
293 |
|
294 |
|
295 |
VERTEX * |
296 |
vnew(id, x, y, z) /* create a new vertex */ |
297 |
register int id; |
298 |
double x, y, z; |
299 |
{ |
300 |
register int i; |
301 |
|
302 |
if (id > nverts) { /* get some more */ |
303 |
i = nverts; |
304 |
nverts = CHUNKSIZ*((id%CHUNKSIZ)+1); |
305 |
if (vlist == NULL) |
306 |
vlist = (VERTEX *)malloc(nverts*sizeof(VERTEX)); |
307 |
else |
308 |
vlist = (VERTEX *)realloc((char *)vlist, |
309 |
nverts*sizeof(VERTEX)); |
310 |
if (vlist == NULL) { |
311 |
fprintf(stderr, |
312 |
"Out of memory while allocating vertex %d\n", id); |
313 |
exit(1); |
314 |
} |
315 |
while (i < nverts) /* clear what's new */ |
316 |
vlist[i++].flags = 0; |
317 |
} |
318 |
/* assign new vertex */ |
319 |
vlist[id].pos[0] = x; |
320 |
vlist[id].pos[1] = y; |
321 |
vlist[id].pos[2] = z; |
322 |
vlist[id].flags = V_DEFINED; |
323 |
/* return it */ |
324 |
return(&vlist[id]); |
325 |
} |
326 |
|
327 |
|
328 |
syntax(fn, fp, er) /* report syntax error and exit */ |
329 |
char *fn; |
330 |
register FILE *fp; |
331 |
char *er; |
332 |
{ |
333 |
extern long ftell(); |
334 |
register long cpos; |
335 |
register int c; |
336 |
int lineno; |
337 |
|
338 |
if (fp == stdin) |
339 |
fprintf(stderr, "%s: T-mesh format error: %s\n", fn, er); |
340 |
else { |
341 |
cpos = ftell(fp); |
342 |
fseek(fp, 0L, 0); |
343 |
lineno = 1; |
344 |
while (cpos-- > 0) { |
345 |
if ((c = getc(fp)) == EOF) |
346 |
break; |
347 |
if (c == '\n') |
348 |
lineno++; |
349 |
} |
350 |
fprintf(stderr, "%s: T-mesh format error at line %d: %s\n", |
351 |
fn, lineno, er); |
352 |
} |
353 |
exit(1); |
354 |
} |