1 // obj.cxx -- routines to handle "sorta" WaveFront .obj format files.
3 // Written by Curtis Olson, started October 1997.
5 // Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 // (Log is kept at end of this file)
38 // #if defined ( __sun__ )
39 // extern "C" void *memmove(void *, const void *, size_t);
40 // extern "C" void *memset(void *, int, size_t);
43 #include <Include/compiler.h>
47 #include <ctype.h> // isdigit()
49 #include <Debug/logstream.hxx>
50 #include <Misc/fgstream.hxx>
51 #include <Include/fg_constants.h>
52 #include <Main/options.hxx>
53 #include <Math/mat3.h>
54 #include <Math/fg_random.h>
55 #include <Math/point3d.hxx>
56 #include <Math/polar3d.hxx>
57 #include <Misc/stopwatch.hxx>
58 #include <Scenery/tile.hxx>
60 #include "material.hxx"
66 static double normals[MAX_NODES][3];
69 // given three points defining a triangle, calculate the normal
70 static void calc_normal(double p1[3], double p2[3],
71 double p3[3], double normal[3])
76 v1[0] = p2[0] - p1[0]; v1[1] = p2[1] - p1[1]; v1[2] = p2[2] - p1[2];
77 v2[0] = p3[0] - p1[0]; v2[1] = p3[1] - p1[1]; v2[2] = p3[2] - p1[2];
79 MAT3cross_product(normal, v1, v2);
80 MAT3_NORMALIZE_VEC(normal,temp);
82 // fgPrintf( FG_TERRAIN, FG_DEBUG, " Normal = %.2f %.2f %.2f\n",
83 // normal[0], normal[1], normal[2]);
87 #define FG_TEX_CONSTANT 69.0
90 // Calculate texture coordinates for a given point.
91 static Point3D calc_tex_coords(double *node, const Point3D& ref) {
94 // double tmplon, tmplat;
96 // cout << "-> " << node[0] << " " << node[1] << " " << node[2] << endl;
97 // cout << "-> " << ref.x() << " " << ref.y() << " " << ref.z() << endl;
99 cp = Point3D( node[0] + ref.x(),
103 pp = fgCartToPolar3d(cp);
105 // tmplon = pp.lon() * RAD_TO_DEG;
106 // tmplat = pp.lat() * RAD_TO_DEG;
107 // cout << tmplon << " " << tmplat << endl;
109 pp.setx( fmod(RAD_TO_DEG * FG_TEX_CONSTANT * pp.x(), 11.0) );
110 pp.sety( fmod(RAD_TO_DEG * FG_TEX_CONSTANT * pp.y(), 11.0) );
112 if ( pp.x() < 0.0 ) {
113 pp.setx( pp.x() + 11.0 );
116 if ( pp.y() < 0.0 ) {
117 pp.sety( pp.y() + 11.0 );
120 // cout << pp << endl;
126 // Load a .obj file and build the GL fragment list
127 int fgObjLoad( const string& path, fgTILE *t) {
130 double approx_normal[3], normal[3] /*, scale = 0.0 */;
131 // double x, y, z, xmax, xmin, ymax, ymin, zmax, zmin;
132 // GLfloat sgenparams[] = { 1.0, 0.0, 0.0, 0.0 };
133 GLint display_list = 0;
135 int in_fragment = 0, in_faces = 0, vncount;
136 int n1 = 0, n2 = 0, n3 = 0, n4 = 0;
137 int last1 = 0, last2 = 0, odd = 0;
141 // printf("loading %s\n", path.c_str() );
143 // Attempt to open "path.gz" or "path"
144 fg_gzifstream in( path );
146 FG_LOG( FG_TERRAIN, FG_ALERT, "Cannot open file: " << path );
150 shading = current_options.get_shading();
155 t->bounding_radius = 0.0;
162 // ignore initial comments and blank lines. (priming the pump)
163 // in >> skipcomment;
166 while ( ! in.eof() ) {
172 if ( in.get( c ) && c == '#' ) {
173 // process a comment line
175 // getline( in, line );
176 // cout << "comment = " << line << endl;
180 if ( token == "gbs" ) {
181 // reference point (center offset)
182 in >> t->center >> t->bounding_radius;
184 // cout << "center = " << center
185 // << " radius = " << t->bounding_radius << endl;
186 } else if ( token == "bs" ) {
187 // reference point (center offset)
188 in >> fragment.center;
189 in >> fragment.bounding_radius;
191 // cout << "center = " << fragment.center
192 // << " radius = " << fragment.bounding_radius << endl;
193 } else if ( token == "usemtl" ) {
194 // material property specification
196 // series of individual triangles
201 // this also signals the start of a new fragment
203 // close out the previous structure and start the next
205 // printf("xglEnd(); xglEndList();\n");
208 fragment.display_list = display_list;
210 // push this fragment onto the tile's object list
211 t->fragment_list.push_back(fragment);
216 // printf("start of fragment (usemtl)\n");
218 display_list = xglGenLists(1);
219 xglNewList(display_list, GL_COMPILE);
220 // printf("xglGenLists(); xglNewList();\n");
223 // reset the existing face list
224 // printf("cleaning a fragment with %d faces\n",
225 // fragment.faces.size());
228 // scan the material line
231 fragment.tile_ptr = t;
233 // find this material in the properties list
234 if ( ! material_mgr.find( material, fragment.material_ptr )) {
235 FG_LOG( FG_TERRAIN, FG_ALERT,
236 "Ack! unknown usemtl name = " << material
240 // initialize the fragment transformation matrix
242 for ( i = 0; i < 16; i++ ) {
243 fragment.matrix[i] = 0.0;
245 fragment.matrix[0] = fragment.matrix[5] =
246 fragment.matrix[10] = fragment.matrix[15] = 1.0;
249 // unknown comment, just gobble the input untill the
259 // cout << "token = " << token << endl;
261 if ( token == "vn" ) {
263 if ( vncount < MAX_NODES ) {
264 in >> normals[vncount][0]
265 >> normals[vncount][1]
266 >> normals[vncount][2];
269 FG_LOG( FG_TERRAIN, FG_ALERT,
270 "Read too many vertex normals ... dying :-(" );
273 } else if ( token == "v" ) {
275 if ( t->ncount < MAX_NODES ) {
276 in >> t->nodes[t->ncount][0]
277 >> t->nodes[t->ncount][1]
278 >> t->nodes[t->ncount][2];
281 FG_LOG( FG_TERRAIN, FG_ALERT,
282 "Read too many nodes ... dying :-(");
285 } else if ( token == "t" ) {
286 // start a new triangle strip
288 n1 = n2 = n3 = n4 = 0;
290 // fgPrintf( FG_TERRAIN, FG_DEBUG,
291 // " new tri strip = %s", line);
292 in >> n1 >> n2 >> n3;
293 fragment.add_face(n1, n2, n3);
295 // fgPrintf( FG_TERRAIN, FG_DEBUG, "(t) = ");
297 xglBegin(GL_TRIANGLE_STRIP);
298 // printf("xglBegin(tristrip) %d %d %d\n", n1, n2, n3);
304 // Shading model is "GL_SMOOTH" so use precalculated
305 // (averaged) normals
306 // MAT3_SCALE_VEC(normal, normals[n1], scale);
307 xglNormal3dv(normal);
308 pp = calc_tex_coords(nodes[n1], center);
309 xglTexCoord2f(pp.lon(), pp.lat());
310 xglVertex3dv(nodes[n1]);
312 // MAT3_SCALE_VEC(normal, normals[n2], scale);
313 xglNormal3dv(normal);
314 pp = calc_tex_coords(nodes[n2], center);
315 xglTexCoord2f(pp.lon(), pp.lat());
316 xglVertex3dv(nodes[n2]);
318 // MAT3_SCALE_VEC(normal, normals[n3], scale);
319 xglNormal3dv(normal);
320 pp = calc_tex_coords(nodes[n3], center);
321 xglTexCoord2f(pp.lon(), pp.lat());
322 xglVertex3dv(nodes[n3]);
324 // Shading model is "GL_FLAT" so calculate per face
325 // normals on the fly.
327 calc_normal(nodes[n1], nodes[n2],
328 nodes[n3], approx_normal);
330 calc_normal(nodes[n2], nodes[n1],
331 nodes[n3], approx_normal);
333 // MAT3_SCALE_VEC(normal, approx_normal, scale);
334 xglNormal3dv(normal);
336 pp = calc_tex_coords(nodes[n1], center);
337 xglTexCoord2f(pp.lon(), pp.lat());
338 xglVertex3dv(nodes[n1]);
340 pp = calc_tex_coords(nodes[n2], center);
341 xglTexCoord2f(pp.lon(), pp.lat());
342 xglVertex3dv(nodes[n2]);
344 pp = calc_tex_coords(nodes[n3], center);
345 xglTexCoord2f(pp.lon(), pp.lat());
346 xglVertex3dv(nodes[n3]);
348 // printf("some normals, texcoords, and vertices\n");
354 // There can be three or four values
356 while ( in.get(c) ) {
358 break; // only the one
368 fragment.add_face(n3, n2, n4);
371 // Shading model is "GL_SMOOTH"
372 // MAT3_SCALE_VEC(normal, normals[n4], scale);
374 // Shading model is "GL_FLAT"
375 calc_normal(nodes[n3], nodes[n2], nodes[n4],
377 // MAT3_SCALE_VEC(normal, approx_normal, scale);
379 xglNormal3dv(normal);
380 pp = calc_tex_coords(nodes[n4], center);
381 xglTexCoord2f(pp.lon(), pp.lat());
382 xglVertex3dv(nodes[n4]);
387 // printf("a normal, texcoord, and vertex (4th)\n");
389 } else if ( token == "tf" ) {
391 // fgPrintf( FG_TERRAIN, FG_DEBUG, "new fan");
393 xglBegin(GL_TRIANGLE_FAN);
396 xglNormal3dv(normals[n1]);
397 pp = calc_tex_coords(nodes[n1], center);
398 xglTexCoord2f(pp.lon(), pp.lat());
399 xglVertex3dv(nodes[n1]);
402 xglNormal3dv(normals[n2]);
403 pp = calc_tex_coords(nodes[n2], center);
404 xglTexCoord2f(pp.lon(), pp.lat());
405 xglVertex3dv(nodes[n2]);
407 // read all subsequent numbers until next thing isn't a number
414 if ( ! isdigit(c) || in.eof() ) {
419 // cout << " triangle = "
420 // << n1 << "," << n2 << "," << n3
422 xglNormal3dv(normals[n3]);
423 pp = calc_tex_coords(nodes[n3], center);
424 xglTexCoord2f(pp.lon(), pp.lat());
425 xglVertex3dv(nodes[n3]);
427 fragment.add_face(n1, n2, n3);
432 } else if ( token == "f" ) {
436 xglBegin(GL_TRIANGLES);
437 // printf("xglBegin(triangles)\n");
441 // fgPrintf( FG_TERRAIN, FG_DEBUG, "new triangle = %s", line);*/
442 in >> n1 >> n2 >> n3;
443 fragment.add_face(n1, n2, n3);
445 // xglNormal3d(normals[n1][0], normals[n1][1], normals[n1][2]);
446 xglNormal3dv(normals[n1]);
447 pp = calc_tex_coords(nodes[n1], center);
448 xglTexCoord2f(pp.lon(), pp.lat());
449 xglVertex3dv(nodes[n1]);
451 xglNormal3dv(normals[n2]);
452 pp = calc_tex_coords(nodes[n2], center);
453 xglTexCoord2f(pp.lon(), pp.lat());
454 xglVertex3dv(nodes[n2]);
456 xglNormal3dv(normals[n3]);
457 pp = calc_tex_coords(nodes[n3], center);
458 xglTexCoord2f(pp.lon(), pp.lat());
459 xglVertex3dv(nodes[n3]);
460 // printf("some normals, texcoords, and vertices (tris)\n");
461 } else if ( token == "q" ) {
462 // continue a triangle strip
465 // fgPrintf( FG_TERRAIN, FG_DEBUG, "continued tri strip = %s ",
469 // There can be one or two values
471 while ( in.get(c) ) {
473 break; // only the one
482 // fgPrintf( FG_TERRAIN, FG_DEBUG, "read %d %d\n", n1, n2);
485 fragment.add_face(last1, last2, n1);
487 fragment.add_face(last2, last1, n1);
491 // Shading model is "GL_SMOOTH"
492 // MAT3_SCALE_VEC(normal, normals[n1], scale);
494 // Shading model is "GL_FLAT"
496 calc_normal(nodes[last1], nodes[last2], nodes[n1],
499 calc_normal(nodes[last2], nodes[last1], nodes[n1],
502 // MAT3_SCALE_VEC(normal, approx_normal, scale);
504 xglNormal3dv(normal);
506 pp = calc_tex_coords(nodes[n1], center);
507 xglTexCoord2f(pp.lon(), pp.lat());
508 xglVertex3dv(nodes[n1]);
509 // printf("a normal, texcoord, and vertex (4th)\n");
516 // fgPrintf( FG_TERRAIN, FG_DEBUG, " (cont)\n");
519 fragment.add_face(last1, last2, n2);
521 fragment.add_face(last2, last1, n2);
525 // Shading model is "GL_SMOOTH"
526 // MAT3_SCALE_VEC(normal, normals[n2], scale);
528 // Shading model is "GL_FLAT"
530 calc_normal(nodes[last1], nodes[last2],
531 nodes[n2], approx_normal);
533 calc_normal(nodes[last2], nodes[last1],
534 nodes[n2], approx_normal);
536 // MAT3_SCALE_VEC(normal, approx_normal, scale);
538 xglNormal3dv(normal);
540 pp = calc_tex_coords(nodes[n2], center);
541 xglTexCoord2f(pp.lon(), pp.lat());
542 xglVertex3dv(nodes[n2]);
543 // printf("a normal, texcoord, and vertex (4th)\n");
550 FG_LOG( FG_TERRAIN, FG_WARN, "Unknown token in "
551 << path << " = " << token );
554 // eat white space before start of while loop so if we are
555 // done with useful input it is noticed before hand.
561 // close out the previous structure and start the next
564 // printf("xglEnd(); xglEndList();\n");
567 fragment.display_list = display_list;
569 // push this fragment onto the tile's object list
570 t->fragment_list.push_back(fragment);
574 // Draw normal vectors (for visually verifying normals)
576 xglColor3f(0.0, 0.0, 0.0);
577 for ( i = 0; i < t->ncount; i++ ) {
578 xglVertex3d(t->nodes[i][0],
581 xglVertex3d(t->nodes[i][0] + 500*normals[i][0],
582 t->nodes[i][1] + 500*normals[i][1],
583 t->nodes[i][2] + 500*normals[i][2]);
589 FG_LOG( FG_TERRAIN, FG_INFO,
590 "Loaded " << path << " in "
591 << stopwatch.elapsedSeconds() << " seconds" );
598 // Revision 1.15 1999/03/31 13:25:58 curt
599 // Removed some debugging output.
601 // Revision 1.14 1999/03/30 23:48:24 curt
602 // modifications to obj loader to handle tri fans.
604 // Revision 1.13 1999/03/27 05:36:03 curt
605 // Alas, I have made non-backwardsly compatible changes to the scenery file
606 // format. Thus I have had to make the corresponding changes here in the
608 // Things that do not correspond the the .obj format are placed in comments.
610 // Revision 1.12 1999/03/02 01:03:25 curt
611 // Tweaks for building with native SGI compilers.
613 // Revision 1.11 1999/02/26 22:09:59 curt
614 // Added initial support for native SGI compilers.
616 // Revision 1.10 1998/11/06 21:18:18 curt
617 // Converted to new logstream debugging facility. This allows release
618 // builds with no messages at all (and no performance impact) by using
619 // the -DFG_NDEBUG flag.
621 // Revision 1.9 1998/11/06 14:47:06 curt
622 // Changes to track Bernie's updates to fgstream.
624 // Revision 1.8 1998/10/20 18:33:55 curt
625 // Tweaked texture coordinates, but we still have some problems. :-(
627 // Revision 1.7 1998/10/20 15:48:44 curt
628 // Removed an extraneous output message.
630 // Revision 1.6 1998/10/18 01:17:21 curt
633 // Revision 1.5 1998/10/16 00:54:39 curt
634 // Converted to Point3D class.
636 // Revision 1.4 1998/09/15 01:35:07 curt
637 // cleaned up my fragment.num_faces hack :-) to use the STL (no need in
638 // duplicating work.)
639 // Tweaked fgTileMgrRender() do not calc tile matrix unless necessary.
640 // removed some unneeded stuff from fgTileMgrCurElev()
642 // Revision 1.3 1998/09/03 21:27:03 curt
643 // Fixed a serious bug caused by not-quite-correct comment/white space eating
644 // which resulted in mismatched glBegin() glEnd() pairs, incorrect display lists,
645 // and ugly display artifacts.
647 // Revision 1.2 1998/09/01 19:03:09 curt
648 // Changes contributed by Bernie Bright <bbright@c031.aone.net.au>
649 // - The new classes in libmisc.tgz define a stream interface into zlib.
650 // I've put these in a new directory, Lib/Misc. Feel free to rename it
651 // to something more appropriate. However you'll have to change the
652 // include directives in all the other files. Additionally you'll have
653 // add the library to Lib/Makefile.am and Simulator/Main/Makefile.am.
655 // The StopWatch class in Lib/Misc requires a HAVE_GETRUSAGE autoconf
656 // test so I've included the required changes in config.tgz.
658 // There are a fair few changes to Simulator/Objects as I've moved
659 // things around. Loading tiles is quicker but thats not where the delay
660 // is. Tile loading takes a few tenths of a second per file on a P200
661 // but it seems to be the post-processing that leads to a noticeable
662 // blip in framerate. I suppose its time to start profiling to see where
665 // I've included a brief description of each archives contents.
670 // C++ stream interface into zlib.
671 // Taken from zlib-1.1.3/contrib/iostream/.
672 // Minor mods for STL compatibility.
673 // There's no copyright associated with these so I assume they're
674 // covered by zlib's.
678 // FlightGear input stream using gz_ifstream. Tries to open the
679 // given filename. If that fails then filename is examined and a
680 // ".gz" suffix is removed or appended and that file is opened.
683 // A simple timer for benchmarking. Not used in production code.
684 // Taken from the Blitz++ project. Covered by GPL.
688 // Some simple string manipulation routines.
690 // Simulator/Airports/
691 // Load airports database using fgstream.
692 // Changed fgAIRPORTS to use set<> instead of map<>.
693 // Added bool fgAIRPORTS::search() as a neater way doing the lookup.
694 // Returns true if found.
697 // Modified fgStarsInit() to load stars database using fgstream.
699 // Simulator/Objects/
700 // Modified fgObjLoad() to use fgstream.
701 // Modified fgMATERIAL_MGR::load_lib() to use fgstream.
702 // Many changes to fgMATERIAL.
703 // Some changes to fgFRAGMENT but I forget what!
705 // Revision 1.1 1998/08/25 16:51:25 curt
706 // Moved from ../Scenery
708 // Revision 1.23 1998/08/20 15:16:43 curt
709 // obj.cxx: use more explicit parenthases.
710 // texload.[ch]: use const in function definitions where appropriate.
712 // Revision 1.22 1998/08/20 15:12:03 curt
713 // Used a forward declaration of classes fgTILE and fgMATERIAL to eliminate
714 // the need for "void" pointers and casts.
715 // Quick hack to count the number of scenery polygons that are being drawn.
717 // Revision 1.21 1998/08/12 21:13:04 curt
718 // material.cxx: don't load textures if they are disabled
719 // obj.cxx: optimizations from Norman Vine
720 // tile.cxx: minor tweaks
721 // tile.hxx: addition of num_faces
722 // tilemgr.cxx: minor tweaks
724 // Revision 1.20 1998/07/24 21:42:07 curt
725 // material.cxx: whups, double method declaration with no definition.
726 // obj.cxx: tweaks to avoid errors in SGI's CC.
727 // tile.cxx: optimizations by Norman Vine.
728 // tilemgr.cxx: optimizations by Norman Vine.
730 // Revision 1.19 1998/07/13 21:01:58 curt
731 // Wrote access functions for current fgOPTIONS.
733 // Revision 1.18 1998/07/12 03:18:27 curt
734 // Added ground collision detection. This involved:
735 // - saving the entire vertex list for each tile with the tile records.
736 // - saving the face list for each fragment with the fragment records.
737 // - code to intersect the current vertical line with the proper face in
738 // an efficient manner as possible.
739 // Fixed a bug where the tiles weren't being shifted to "near" (0,0,0)
741 // Revision 1.17 1998/07/08 14:47:21 curt
742 // Fix GL_MODULATE vs. GL_DECAL problem introduced by splash screen.
743 // polare3d.h renamed to polar3d.hxx
744 // fg{Cartesian,Polar}Point3d consolodated.
745 // Added some initial support for calculating local current ground elevation.
747 // Revision 1.16 1998/07/06 21:34:33 curt
748 // Added using namespace std for compilers that support this.
750 // Revision 1.15 1998/07/04 00:54:28 curt
751 // Added automatic mipmap generation.
753 // When rendering fragments, use saved model view matrix from associated tile
754 // rather than recalculating it with push() translate() pop().
756 // Revision 1.14 1998/06/17 21:36:40 curt
757 // Load and manage multiple textures defined in the Materials library.
758 // Boost max material fagments for each material property to 800.
759 // Multiple texture support when rendering.
761 // Revision 1.13 1998/06/12 00:58:05 curt
762 // Build only static libraries.
763 // Declare memmove/memset for Sloaris.
765 // Revision 1.12 1998/06/08 17:57:54 curt
766 // Working first pass at material proporty sorting.
768 // Revision 1.11 1998/06/06 01:09:31 curt
769 // I goofed on the log message in the last commit ... now fixed.
771 // Revision 1.10 1998/06/06 01:07:17 curt
772 // Increased per material fragment list size from 100 to 400.
773 // Now correctly draw viewable fragments in per material order.
775 // Revision 1.9 1998/06/05 22:39:54 curt
776 // Working on sorting by, and rendering by material properties.
778 // Revision 1.8 1998/06/05 18:19:18 curt
779 // Recognize file, file.gz, and file.obj as scenery object files.
781 // Revision 1.7 1998/05/24 02:49:09 curt
782 // Implimented fragment level view frustum culling.
784 // Revision 1.6 1998/05/23 14:09:20 curt
785 // Added tile.cxx and tile.hxx.
786 // Working on rewriting the tile management system so a tile is just a list
787 // fragments, and the fragment record contains the display list for that
790 // Revision 1.5 1998/05/20 20:53:53 curt
791 // Moved global ref point and radius (bounding sphere info, and offset) to
792 // data file rather than calculating it on the fly.
793 // Fixed polygon winding problem in scenery generation stage rather than
794 // compensating for it on the fly.
795 // Made a fgTILECACHE class.
797 // Revision 1.4 1998/05/16 13:09:57 curt
798 // Beginning to add support for view frustum culling.
799 // Added some temporary code to calculate bouding radius, until the
800 // scenery generation tools and scenery can be updated.
802 // Revision 1.3 1998/05/03 00:48:01 curt
803 // Updated texture coordinate fmod() parameter.
805 // Revision 1.2 1998/05/02 01:52:14 curt
806 // Playing around with texture coordinates.
808 // Revision 1.1 1998/04/30 12:35:28 curt
809 // Added a command line rendering option specify smooth/flat shading.
811 // Revision 1.35 1998/04/28 21:43:26 curt
812 // Wrapped zlib calls up so we can conditionally comment out zlib support.
814 // Revision 1.34 1998/04/28 01:21:42 curt
815 // Tweaked texture parameter calculations to keep the number smaller. This
816 // avoids the "swimming" problem.
817 // Type-ified fgTIME and fgVIEW.
819 // Revision 1.33 1998/04/27 15:58:15 curt
820 // Screwing around with texture coordinate generation ... still needs work.
822 // Revision 1.32 1998/04/27 03:30:13 curt
823 // Minor transformation adjustments to try to keep scenery tiles closer to
824 // (0, 0, 0) GLfloats run out of precision at the distances we need to model
825 // the earth, but we can do a bunch of pre-transformations using double math
826 // and then cast to GLfloat once everything is close in where we have less
827 // precision problems.
829 // Revision 1.31 1998/04/25 15:09:57 curt
830 // Changed "r" to "rb" in gzopen() options. This fixes bad behavior in win32.
832 // Revision 1.30 1998/04/24 14:21:08 curt
833 // Added "file.obj.gz" support.
835 // Revision 1.29 1998/04/24 00:51:07 curt
836 // Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
837 // Tweaked the scenery file extentions to be "file.obj" (uncompressed)
838 // or "file.obz" (compressed.)
840 // Revision 1.28 1998/04/22 13:22:44 curt
841 // C++ - ifing the code a bit.
843 // Revision 1.27 1998/04/18 04:13:17 curt
844 // Added zlib on the fly decompression support for loading scenery objects.
846 // Revision 1.26 1998/04/03 22:11:36 curt
847 // Converting to Gnu autoconf system.
849 // Revision 1.25 1998/03/14 00:30:50 curt
850 // Beginning initial terrain texturing experiments.
852 // Revision 1.24 1998/02/09 21:30:18 curt
853 // Fixed a nagging problem with terrain tiles not "quite" matching up perfectly.
855 // Revision 1.23 1998/02/09 15:07:52 curt
858 // Revision 1.22 1998/02/01 03:39:54 curt
861 // Revision 1.21 1998/01/31 00:43:25 curt
862 // Added MetroWorks patches from Carmen Volpe.
864 // Revision 1.20 1998/01/29 00:51:39 curt
865 // First pass at tile cache, dynamic tile loading and tile unloading now works.
867 // Revision 1.19 1998/01/27 03:26:42 curt
868 // Playing with new fgPrintf command.
870 // Revision 1.18 1998/01/19 19:27:16 curt
871 // Merged in make system changes from Bob Kuehne <rpk@sgi.com>
872 // This should simplify things tremendously.
874 // Revision 1.17 1998/01/13 00:23:10 curt
875 // Initial changes to support loading and management of scenery tiles. Note,
876 // there's still a fair amount of work left to be done.
878 // Revision 1.16 1997/12/30 23:09:40 curt
879 // Worked on winding problem without luck, so back to calling glFrontFace()
880 // 3 times for each scenery area.
882 // Revision 1.15 1997/12/30 20:47:51 curt
883 // Integrated new event manager with subsystem initializations.
885 // Revision 1.14 1997/12/30 01:38:46 curt
886 // Switched back to per vertex normals and smooth shading for terrain.
888 // Revision 1.13 1997/12/18 23:32:36 curt
889 // First stab at sky dome actually starting to look reasonable. :-)
891 // Revision 1.12 1997/12/17 23:13:47 curt
892 // Began working on rendering the sky.
894 // Revision 1.11 1997/12/15 23:55:01 curt
895 // Add xgl wrappers for debugging.
896 // Generate terrain normals on the fly.
898 // Revision 1.10 1997/12/12 21:41:28 curt
899 // More light/material property tweaking ... still a ways off.
901 // Revision 1.9 1997/12/12 19:52:57 curt
902 // Working on lightling and material properties.
904 // Revision 1.8 1997/12/10 01:19:51 curt
905 // Tweaks for verion 0.15 release.
907 // Revision 1.7 1997/12/08 22:51:17 curt
908 // Enhanced to handle ccw and cw tri-stripe winding. This is a temporary
909 // admission of defeat. I will eventually go back and get all the stripes
910 // wound the same way (ccw).
912 // Revision 1.6 1997/11/25 19:25:35 curt
913 // Changes to integrate Durk's moon/sun code updates + clean up.
915 // Revision 1.5 1997/11/15 18:16:39 curt
918 // Revision 1.4 1997/11/14 00:26:49 curt
919 // Transform scenery coordinates earlier in pipeline when scenery is being
920 // created, not when it is being loaded. Precalculate normals for each node
921 // as average of the normals of each containing polygon so Garoude shading is
924 // Revision 1.3 1997/10/31 04:49:12 curt
925 // Tweaking vertex orders.
927 // Revision 1.2 1997/10/30 12:38:45 curt
928 // Working on new scenery subsystem.
930 // Revision 1.1 1997/10/28 21:14:54 curt