1 /* tri2obj.c -- read in a .ele/.node file pair generated by the triangle
2 * program and output a simple Wavefront .obj file.
4 * Written by Curtis Olson, started October 1997.
6 * Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 * (Log is kept at end of this file)
28 #include <stdlib.h> /* for atoi() */
30 #include <sys/stat.h> /* for stat() */
31 #include <unistd.h> /* for stat() */
35 #include <Include/fg_constants.h>
36 #include <Include/fg_types.h>
37 #include <Math/fg_geodesy.h>
38 #include <Math/mat3.h>
39 #include <Math/polar.h>
40 #include <Scenery/bucketutils.h>
43 int nodecount, tricount;
45 static struct fgCartesianPoint nodes[MAX_NODES];
46 static int tris[MAX_TRIS][3];
48 static double normals[MAX_NODES][3];
50 struct fgBUCKET my_index;
51 struct fgBUCKET ne_index, nw_index, sw_index, se_index;
52 struct fgBUCKET north_index, south_index, east_index, west_index;
54 /* convert a geodetic point lon(arcsec), lat(arcsec), elev(meter) to
55 * a cartesian point */
56 struct fgCartesianPoint geod_to_cart(double geod[3]) {
57 struct fgCartesianPoint p;
58 double gc_lon, gc_lat, sl_radius;
60 /* printf("A geodetic point is (%.2f, %.2f, %.2f)\n",
61 geod[0], geod[1], geod[2]); */
63 gc_lon = geod[0]*ARCSEC_TO_RAD;
64 fgGeodToGeoc(geod[1]*ARCSEC_TO_RAD, geod[2], &sl_radius, &gc_lat);
66 /* printf("A geocentric point is (%.2f, %.2f, %.2f)\n", gc_lon,
67 gc_lat, sl_radius+geod[2]); */
69 p = fgPolarToCart(gc_lon, gc_lat, sl_radius+geod[2]);
71 /* printf("A cart point is (%.8f, %.8f, %.8f)\n", p.x, p.y, p.z); */
77 /* given three points defining a triangle, calculate the normal */
78 void calc_normal(struct fgCartesianPoint p1, struct fgCartesianPoint p2,
79 struct fgCartesianPoint p3, double normal[3])
84 v1[0] = p2.x - p1.x; v1[1] = p2.y - p1.y; v1[2] = p2.z - p1.z;
85 v2[0] = p3.x - p1.x; v2[1] = p3.y - p1.y; v2[2] = p3.z - p1.z;
87 MAT3cross_product(normal, v1, v2);
88 MAT3_NORMALIZE_VEC(normal, temp);
90 /* printf(" Normal = %.2f %.2f %.2f\n", normal[0], normal[1], normal[2]); */
94 /* return the index of all triangles containing the specified node */
95 void find_tris(int n, int *t1, int *t2, int *t3, int *t4, int *t5) {
98 *t1 = *t2 = *t3 = *t4 = *t5 = 0;
101 while ( i <= tricount ) {
102 if ( (n == tris[i][0]) || (n == tris[i][1]) || (n == tris[i][2]) ) {
105 } else if ( *t2 == 0 ) {
107 } else if ( *t3 == 0 ) {
109 } else if ( *t4 == 0 ) {
120 /* return the file base name ( foo/bar/file.ext = file.ext ) */
121 void extract_file(char *in, char *base) {
127 while ( (i >= 0) && (in[i] != '/') ) {
136 /* return the file path name ( foo/bar/file.ext = foo/bar ) */
137 void extract_path(char *in, char *base) {
144 while ( (i >= 0) && (in[i] != '/') ) {
152 /* check if a file exists */
153 int file_exists(char *file) {
154 struct stat stat_buf;
157 printf("checking %s ... ", file);
159 result = stat(file, &stat_buf);
162 /* stat failed, no file */
163 printf("not found.\n");
166 /* stat succeeded, file exists */
173 /* check to see if a shared object exists */
174 int shared_object_exists(char *basepath, char *ext, char *file) {
175 char scene_path[256];
178 if ( strcmp(ext, ".sw") == 0 ) {
179 fgBucketGenBasePath(&my_index, scene_path);
180 index = fgBucketGenIndex(&my_index);
181 sprintf(file, "%s/%s/%ld.1.sw", basepath, scene_path, index);
182 if ( file_exists(file) ) {
185 fgBucketGenBasePath(&west_index, scene_path);
186 index = fgBucketGenIndex(&west_index);
187 sprintf(file, "%s/%s/%ld.1.se", basepath, scene_path, index);
188 if ( file_exists(file) ) {
191 fgBucketGenBasePath(&sw_index, scene_path);
192 index = fgBucketGenIndex(&sw_index);
193 sprintf(file, "%s/%s/%ld.1.ne", basepath, scene_path, index);
194 if ( file_exists(file) ) {
197 fgBucketGenBasePath(&south_index, scene_path);
198 index = fgBucketGenIndex(&south_index);
199 sprintf(file, "%s/%s/%ld.1.nw", basepath, scene_path, index);
200 if ( file_exists(file) ) {
205 if ( strcmp(ext, ".se") == 0 ) {
206 fgBucketGenBasePath(&my_index, scene_path);
207 index = fgBucketGenIndex(&my_index);
208 sprintf(file, "%s/%s/%ld.1.se", basepath, scene_path, index);
209 if ( file_exists(file) ) {
212 fgBucketGenBasePath(&east_index, scene_path);
213 index = fgBucketGenIndex(&east_index);
214 sprintf(file, "%s/%s/%ld.1.sw", basepath, scene_path, index);
215 if ( file_exists(file) ) {
218 fgBucketGenBasePath(&se_index, scene_path);
219 index = fgBucketGenIndex(&se_index);
220 sprintf(file, "%s/%s/%ld.1.nw", basepath, scene_path, index);
221 if ( file_exists(file) ) {
224 fgBucketGenBasePath(&south_index, scene_path);
225 index = fgBucketGenIndex(&south_index);
226 sprintf(file, "%s/%s/%ld.1.ne", basepath, scene_path, index);
227 if ( file_exists(file) ) {
232 if ( strcmp(ext, ".ne") == 0 ) {
233 fgBucketGenBasePath(&my_index, scene_path);
234 index = fgBucketGenIndex(&my_index);
235 sprintf(file, "%s/%s/%ld.1.ne", basepath, scene_path, index);
236 if ( file_exists(file) ) {
239 fgBucketGenBasePath(&east_index, scene_path);
240 index = fgBucketGenIndex(&east_index);
241 sprintf(file, "%s/%s/%ld.1.nw", basepath, scene_path, index);
242 if ( file_exists(file) ) {
245 fgBucketGenBasePath(&ne_index, scene_path);
246 index = fgBucketGenIndex(&ne_index);
247 sprintf(file, "%s/%s/%ld.1.sw", basepath, scene_path, index);
248 if ( file_exists(file) ) {
251 fgBucketGenBasePath(&north_index, scene_path);
252 index = fgBucketGenIndex(&north_index);
253 sprintf(file, "%s/%s/%ld.1.se", basepath, scene_path, index);
254 if ( file_exists(file) ) {
259 if ( strcmp(ext, ".nw") == 0 ) {
260 fgBucketGenBasePath(&my_index, scene_path);
261 index = fgBucketGenIndex(&my_index);
262 sprintf(file, "%s/%s/%ld.1.nw", basepath, scene_path, index);
263 if ( file_exists(file) ) {
266 fgBucketGenBasePath(&west_index, scene_path);
267 index = fgBucketGenIndex(&west_index);
268 sprintf(file, "%s/%s/%ld.1.ne", basepath, scene_path, index);
269 if ( file_exists(file) ) {
272 fgBucketGenBasePath(&nw_index, scene_path);
273 index = fgBucketGenIndex(&nw_index);
274 sprintf(file, "%s/%s/%ld.1.se", basepath, scene_path, index);
275 if ( file_exists(file) ) {
278 fgBucketGenBasePath(&north_index, scene_path);
279 index = fgBucketGenIndex(&north_index);
280 sprintf(file, "%s/%s/%ld.1.sw", basepath, scene_path, index);
281 if ( file_exists(file) ) {
286 if ( strcmp(ext, ".south") == 0 ) {
287 fgBucketGenBasePath(&my_index, scene_path);
288 index = fgBucketGenIndex(&my_index);
289 sprintf(file, "%s/%s/%ld.1.south", basepath, scene_path, index);
290 if ( file_exists(file) ) {
293 fgBucketGenBasePath(&south_index, scene_path);
294 index = fgBucketGenIndex(&south_index);
295 sprintf(file, "%s/%s/%ld.1.north", basepath, scene_path, index);
296 if ( file_exists(file) ) {
301 if ( strcmp(ext, ".north") == 0 ) {
302 fgBucketGenBasePath(&my_index, scene_path);
303 index = fgBucketGenIndex(&my_index);
304 sprintf(file, "%s/%s/%ld.1.north", basepath, scene_path, index);
305 if ( file_exists(file) ) {
308 fgBucketGenBasePath(&north_index, scene_path);
309 index = fgBucketGenIndex(&north_index);
310 sprintf(file, "%s/%s/%ld.1.south", basepath, scene_path, index);
311 if ( file_exists(file) ) {
316 if ( strcmp(ext, ".west") == 0 ) {
317 fgBucketGenBasePath(&my_index, scene_path);
318 index = fgBucketGenIndex(&my_index);
319 sprintf(file, "%s/%s/%ld.1.west", basepath, scene_path, index);
320 if ( file_exists(file) ) {
323 fgBucketGenBasePath(&west_index, scene_path);
324 index = fgBucketGenIndex(&west_index);
325 sprintf(file, "%s/%s/%ld.1.east", basepath, scene_path, index);
326 if ( file_exists(file) ) {
331 if ( strcmp(ext, ".east") == 0 ) {
332 fgBucketGenBasePath(&my_index, scene_path);
333 index = fgBucketGenIndex(&my_index);
334 sprintf(file, "%s/%s/%ld.1.east", basepath, scene_path, index);
335 if ( file_exists(file) ) {
338 fgBucketGenBasePath(&east_index, scene_path);
339 index = fgBucketGenIndex(&east_index);
340 sprintf(file, "%s/%s/%ld.1.west", basepath, scene_path, index);
341 if ( file_exists(file) ) {
346 if ( strcmp(ext, ".body") == 0 ) {
347 fgBucketGenBasePath(&my_index, scene_path);
348 index = fgBucketGenIndex(&my_index);
349 sprintf(file, "%s/%s/%ld.1.body", basepath, scene_path, index);
350 if ( file_exists(file) ) {
359 /* given a file pointer, read all the vn (normals from it) */
360 void read_normals(FILE *fp) {
363 while ( fgets(line, 250, fp) != NULL ) {
364 if ( strncmp(line, "vn ", 3) == 0 ) {
365 sscanf( line, "vn %lf %lf %lf\n",
366 &normals[normalcount][0],
367 &normals[normalcount][1],
368 &normals[normalcount][2] );
370 printf("read_normals(%d) %.2f %.2f %.2f %s", normalcount,
371 normals[normalcount][0], normals[normalcount][1],
372 normals[normalcount][2], line);
380 /* my custom file opening routine ... don't open if a shared edge or
381 * vertex alread exists */
382 FILE *my_open(char *basename, char *basepath, char *ext) {
386 /* check if a shared object already exists */
387 if ( shared_object_exists(basepath, ext, filename) ) {
388 /* not an actual file open error, but we've already got the
389 * shared edge, so we don't want to create another one */
390 fp = fopen(filename, "r");
391 printf("Opening %s\n", filename);
395 printf("not opening\n");
401 /* Initialize a new mesh structure */
402 void triload(char *basename, char *basepath) {
403 char nodename[256], elename[256];
405 FILE *ne, *nw, *se, *sw, *north, *south, *east, *west;
407 int dim, junk1, junk2;
410 ne = my_open(basename, basepath, ".ne");
414 nw = my_open(basename, basepath, ".nw");
418 se = my_open(basename, basepath, ".se");
422 sw = my_open(basename, basepath, ".sw");
426 north = my_open(basename, basepath, ".north");
430 south = my_open(basename, basepath, ".south");
434 east = my_open(basename, basepath, ".east");
438 west = my_open(basename, basepath, ".west");
442 strcpy(nodename, basename);
443 strcat(nodename, ".node");
444 strcpy(elename, basename);
445 strcat(elename, ".ele");
447 printf("Loading node file: %s ...\n", nodename);
448 if ( (node = fopen(nodename, "r")) == NULL ) {
449 printf("Cannot open file '%s'\n", nodename);
453 fscanf(node, "%d %d %d %d", &nodecount, &dim, &junk1, &junk2);
455 if ( nodecount > MAX_NODES - 1 ) {
456 printf("Error, too many nodes, need to increase array size\n");
459 printf(" Expecting %d nodes\n", nodecount);
462 for ( i = 1; i <= nodecount; i++ ) {
463 fscanf(node, "%d %lf %lf %lf %d\n", &junk1,
464 &n[0], &n[1], &n[2], &junk2);
465 /* printf("%d %.2f %.2f %.2f\n", junk1, n[0], n[1], n[2]); */
466 nodes[i] = geod_to_cart(n);
467 /* printf("%d %.2f %.2f %.2f\n",
468 junk1, nodes[i].x, nodes[i].y, nodes[i].z); */
473 printf("Loading element file: %s ...\n", elename);
474 if ( (ele = fopen(elename, "r")) == NULL ) {
475 printf("Cannot open file '%s'\n", elename);
479 fscanf(ele, "%d %d %d", &tricount, &junk1, &junk2);
481 if ( tricount > MAX_TRIS - 1 ) {
482 printf("Error, too many elements, need to increase array size\n");
485 printf(" Expecting %d elements\n", tricount);
488 for ( i = 1; i <= tricount; i++ ) {
489 fscanf(ele, "%d %d %d %d\n", &junk1,
490 &tris[i][0], &tris[i][1], &tris[i][2]);
491 /* printf("%d %d %d %d\n", junk1, tris[i][0], tris[i][1], tris[i][2]);*/
498 /* dump in WaveFront .obj format */
499 void dump_obj(char *basename) {
501 double n1[3], n2[3], n3[3], n4[3], n5[3], norm[3], temp;
503 int i, t1, t2, t3, t4, t5, count;
505 strcpy(objname, basename);
506 strcat(objname, ".obj");
508 printf("Dumping to file: %s ...\n", objname);
510 obj = fopen(objname, "w");
513 printf(" writing vertices\n");
514 for ( i = 1; i <= nodecount; i++ ) {
515 fprintf(obj, "v %.2f %.2f %.2f\n",
516 nodes[i].x, nodes[i].y, nodes[i].z);
519 printf(" calculating and writing normals\n");
520 printf(" First %d normals taken from shared files.\n", normalcount);
522 /* calculate and generate normals */
523 for ( i = 1; i <= nodecount; i++ ) {
525 if ( i <= normalcount ) {
526 /* use precalculated (shared) normal */
527 norm[0] = normals[i-1][0];
528 norm[1] = normals[i-1][1];
529 norm[2] = normals[i-1][2];
531 /* printf("Finding normal\n"); */
533 find_tris(i, &t1, &t2, &t3, &t4, &t5);
535 n1[0] = n1[1] = n1[2] = 0.0;
536 n2[0] = n2[1] = n2[2] = 0.0;
537 n3[0] = n3[1] = n3[2] = 0.0;
538 n4[0] = n4[1] = n4[2] = 0.0;
539 n5[0] = n5[1] = n5[2] = 0.0;
542 calc_normal(nodes[tris[t1][0]], nodes[tris[t1][1]],
543 nodes[tris[t1][2]], n1);
546 calc_normal(nodes[tris[t2][0]], nodes[tris[t2][1]],
547 nodes[tris[t2][2]], n2);
552 calc_normal(nodes[tris[t3][0]], nodes[tris[t3][1]],
553 nodes[tris[t3][2]], n3);
558 calc_normal(nodes[tris[t4][0]], nodes[tris[t4][1]],
559 nodes[tris[t4][2]], n4);
564 calc_normal(nodes[tris[t5][0]], nodes[tris[t5][1]],
565 nodes[tris[t5][2]], n5);
569 /* printf(" norm[2] = %.2f %.2f %.2f\n", n1[2], n2[2], n3[2]); */
571 norm[0] = ( n1[0] + n2[0] + n3[0] + n4[0] + n5[0] ) / (double)count;
572 norm[1] = ( n1[1] + n2[1] + n3[1] + n4[1] + n5[1] ) / (double)count;
573 norm[2] = ( n1[2] + n2[2] + n3[2] + n4[2] + n5[2] ) / (double)count;
575 /* printf(" count = %d\n", count); */
576 /* printf(" Ave. normal = %.4f %.4f %.4f\n",
577 norm[0], norm[1], norm[2]);*/
578 MAT3_NORMALIZE_VEC(norm, temp);
579 /* printf(" Normalized ave. normal = %.4f %.4f %.4f\n", */
580 /* norm[0], norm[1], norm[2]); */
582 /* printf("%d vn %.4f %.4f %.4f\n", i, norm[0], norm[1], norm[2]); */
583 fprintf(obj, "vn %.4f %.4f %.4f\n", norm[0], norm[1], norm[2]);
587 printf(" writing faces\n");
588 for ( i = 1; i <= tricount; i++ ) {
589 fprintf(obj, "f %d %d %d\n", tris[i][0], tris[i][1], tris[i][2]);
595 int main(int argc, char **argv) {
596 char basename[256], basepath[256], temp[256];
600 strcpy(basename, argv[1]);
602 /* find the base path of the file */
603 extract_path(basename, basepath);
604 extract_path(basepath, basepath);
605 extract_path(basepath, basepath);
606 printf("%s\n", basepath);
608 /* find the index of the current file */
609 extract_file(basename, temp);
614 tmp_index = atoi(temp);
615 printf("%ld\n", tmp_index);
616 fgBucketParseIndex(tmp_index, &my_index);
618 printf("bucket = %d %d %d %d\n",
619 my_index.lon, my_index.lat, my_index.x, my_index.y);
620 /* generate the indexes of the neighbors */
621 fgBucketOffset(&my_index, &ne_index, 1, 1);
622 fgBucketOffset(&my_index, &nw_index, -1, 1);
623 fgBucketOffset(&my_index, &se_index, 1, -1);
624 fgBucketOffset(&my_index, &sw_index, -1, -1);
626 fgBucketOffset(&my_index, &north_index, 0, 1);
627 fgBucketOffset(&my_index, &south_index, 0, -1);
628 fgBucketOffset(&my_index, &east_index, 1, 0);
629 fgBucketOffset(&my_index, &west_index, -1, 0);
631 /* load the input data files */
632 triload(basename, basepath);
634 /* dump in WaveFront .obj format */
642 /* Revision 1.11 1998/03/03 16:01:00 curt
643 /* More c++ compile tweaks.
645 * Revision 1.10 1998/01/31 00:41:27 curt
646 * Made a few changes converting floats to doubles.
648 * Revision 1.9 1998/01/27 18:37:04 curt
649 * Lots of updates to get back in sync with changes made over in .../Src/
651 * Revision 1.8 1998/01/17 01:25:39 curt
652 * Added support for shared normals.
654 * Revision 1.7 1998/01/12 02:42:00 curt
655 * Average up to five triangles per vertex instead of three.
657 * Revision 1.6 1998/01/09 23:03:15 curt
658 * Restructured to split 1deg x 1deg dem's into 64 subsections.
660 * Revision 1.5 1997/12/08 19:17:50 curt
661 * Fixed a type in the normal generation code.
663 * Revision 1.4 1997/12/02 13:13:32 curt
664 * Fixed problem with averaged vertex normals.
666 * Revision 1.3 1997/11/15 18:05:05 curt
669 * Revision 1.2 1997/11/14 00:29:13 curt
670 * Transform scenery coordinates at this point in pipeline when scenery is
671 * being translated to .obj format, not when it is being loaded into the end
672 * renderer. Precalculate normals for each node as average of the normals
673 * of each containing polygon so Garoude shading is now supportable.
675 * Revision 1.1 1997/10/29 23:05:15 curt