/* -*- Mode: C++ -*- * * obj.c -- routines to handle WaveFront .obj format files. * * Written by Curtis Olson, started October 1997. * * Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * * $Id$ * (Log is kept at end of this file) **************************************************************************/ #include #ifdef HAVE_WINDOWS_H # include #endif #include #include #include #include #include #include
#include #include #include #include #define MAXNODES 100000 static double nodes[MAXNODES][3]; static double normals[MAXNODES][3]; /* given three points defining a triangle, calculate the normal */ void calc_normal(double p1[3], double p2[3], double p3[3], double normal[3]) { double v1[3], v2[3]; double temp; v1[0] = p2[0] - p1[0]; v1[1] = p2[1] - p1[1]; v1[2] = p2[2] - p1[2]; v2[0] = p3[0] - p1[0]; v2[1] = p3[1] - p1[1]; v2[2] = p3[2] - p1[2]; MAT3cross_product(normal, v1, v2); MAT3_NORMALIZE_VEC(normal,temp); /* fgPrintf( FG_TERRAIN, FG_DEBUG, " Normal = %.2f %.2f %.2f\n", normal[0], normal[1], normal[2]);*/ } #define FG_TEX_CONSTANT 128.0 float calc_lon(double x, double y, double z) { float tmp; tmp = (RAD_TO_DEG*atan2(y, x)) * FG_TEX_CONSTANT; // printf("lon = %.2f\n", (float)tmp); return (float)tmp; } float calc_lat(double x, double y, double z) { float tmp; tmp = (90.0 - RAD_TO_DEG*atan2( sqrt(x*x + y*y), z )) * FG_TEX_CONSTANT; // printf("lat = %.2f\n", (float)tmp); return (float)tmp; } /* Load a .obj file and generate the GL call list */ GLint fgObjLoad(char *path, struct fgCartesianPoint *ref, double *radius) { char line[256], winding_str[256]; double approx_normal[3], normal[3], scale; double x, y, z, xmax, xmin, ymax, ymin, zmax, zmin; GLfloat sgenparams[] = { 1.0, 0.0, 0.0, 0.0 }; GLint tile; FILE *f; int first, ncount, vncount, n1, n2, n3, n4; static int use_per_vertex_norms = 1; int winding; int last1, last2, odd; if ( (f = fopen(path, "r")) == NULL ) { fgPrintf(FG_TERRAIN, FG_ALERT, "Cannot open file: %s\n", path); return(-1); } tile = xglGenLists(1); xglNewList(tile, GL_COMPILE); /* xglTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR); xglTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR); xglTexGenfv(GL_S, GL_OBJECT_PLANE, sgenparams); xglTexGenfv(GL_T, GL_OBJECT_PLANE, sgenparams); // xglTexGenfv(GL_S, GL_SPHERE_MAP, 0); // xglTexGenfv(GL_T, GL_SPHERE_MAP, 0); xglEnable(GL_TEXTURE_GEN_S); xglEnable(GL_TEXTURE_GEN_T); */ first = 1; ncount = 1; vncount = 1; while ( fgets(line, 250, f) != NULL ) { if ( line[0] == '#' ) { /* comment -- ignore */ } else if ( line[0] == '\n' ) { /* empty line -- ignore */ } else if ( strncmp(line, "v ", 2) == 0 ) { /* node (vertex) */ if ( ncount < MAXNODES ) { /* fgPrintf( FG_TERRAIN, FG_DEBUG, "vertex = %s", line); */ sscanf(line, "v %lf %lf %lf\n", &x, &y, &z); nodes[ncount][0] = x; nodes[ncount][1] = y; nodes[ncount][2] = z; /* first time through set min's and max'es */ if ( ncount == 1 ) { xmin = x; xmax = x; ymin = y; ymax = y; zmin = z; zmax = z; } /* keep track of min/max vertex values */ if ( x < xmin ) xmin = x; if ( x > xmax ) xmax = x; if ( y < ymin ) ymin = y; if ( y > ymax ) ymax = y; if ( z < zmin ) zmin = z; if ( z > zmax ) zmax = z; ncount++; } else { fgPrintf( FG_TERRAIN, FG_EXIT, "Read too many nodes ... dying :-(\n"); } } else if ( strncmp(line, "vn ", 3) == 0 ) { /* vertex normal */ if ( vncount < MAXNODES ) { /* fgPrintf( FG_TERRAIN, FG_DEBUG, "vertex normal = %s", line); */ sscanf(line, "vn %lf %lf %lf\n", &normals[vncount][0], &normals[vncount][1], &normals[vncount][2]); vncount++; } else { fgPrintf( FG_TERRAIN, FG_EXIT, "Read too many vertex normals ... dying :-(\n"); } } else if ( strncmp(line, "winding ", 8) == 0 ) { sscanf(line+8, "%s", winding_str); fgPrintf( FG_TERRAIN, FG_DEBUG, " WINDING = %s\n", winding_str); /* can't call xglFrontFace() between xglBegin() & xglEnd() */ xglEnd(); first = 1; if ( strcmp(winding_str, "cw") == 0 ) { xglFrontFace( GL_CW ); winding = 0; } else { glFrontFace ( GL_CCW ); winding = 1; } } else if ( line[0] == 't' ) { /* start a new triangle strip */ n1 = n2 = n3 = n4 = 0; if ( !first ) { /* close out the previous structure and start the next */ xglEnd(); } else { first = 0; } /* fgPrintf( FG_TERRAIN, FG_DEBUG, " new tri strip = %s", line); */ sscanf(line, "t %d %d %d %d\n", &n1, &n2, &n3, &n4); /* fgPrintf( FG_TERRAIN, FG_DEBUG, "(t) = "); */ xglBegin(GL_TRIANGLE_STRIP); if ( winding ) { odd = 1; scale = 1.0; } else { odd = 0; scale = 1.0; } if ( use_per_vertex_norms ) { MAT3_SCALE_VEC(normal, normals[n1], scale); xglNormal3dv(normal); xglTexCoord2f(calc_lon(nodes[n1][0], nodes[n1][1], nodes[n1][2]), calc_lat(nodes[n1][0], nodes[n1][1], nodes[n1][2])); xglVertex3d(nodes[n1][0], nodes[n1][1], nodes[n1][2]); MAT3_SCALE_VEC(normal, normals[n2], scale); xglNormal3dv(normal); xglTexCoord2f(calc_lon(nodes[n2][0], nodes[n2][1], nodes[n2][2]), calc_lat(nodes[n2][0], nodes[n2][1], nodes[n2][2])); xglVertex3d(nodes[n2][0], nodes[n2][1], nodes[n2][2]); MAT3_SCALE_VEC(normal, normals[n3], scale); xglNormal3dv(normal); xglTexCoord2f(calc_lon(nodes[n3][0], nodes[n3][1], nodes[n3][2]), calc_lat(nodes[n3][0], nodes[n3][1], nodes[n3][2])); xglVertex3d(nodes[n3][0], nodes[n3][1], nodes[n3][2]); } else { if ( odd ) { calc_normal(nodes[n1], nodes[n2], nodes[n3], approx_normal); } else { calc_normal(nodes[n2], nodes[n1], nodes[n3], approx_normal); } MAT3_SCALE_VEC(normal, approx_normal, scale); xglNormal3dv(normal); xglTexCoord2f(calc_lon(nodes[n1][0], nodes[n1][1], nodes[n1][2]), calc_lat(nodes[n1][0], nodes[n1][1], nodes[n1][2])); xglVertex3d(nodes[n1][0], nodes[n1][1], nodes[n1][2]); xglTexCoord2f(calc_lon(nodes[n2][0], nodes[n2][1], nodes[n2][2]), calc_lat(nodes[n2][0], nodes[n2][1], nodes[n2][2])); xglVertex3d(nodes[n2][0], nodes[n2][1], nodes[n2][2]); xglTexCoord2f(calc_lon(nodes[n3][0], nodes[n3][1], nodes[n3][2]), calc_lat(nodes[n3][0], nodes[n3][1], nodes[n3][2])); xglVertex3d(nodes[n3][0], nodes[n3][1], nodes[n3][2]); } odd = 1 - odd; last1 = n2; last2 = n3; if ( n4 > 0 ) { if ( use_per_vertex_norms ) { MAT3_SCALE_VEC(normal, normals[n4], scale); } else { calc_normal(nodes[n3], nodes[n2], nodes[n4], approx_normal); MAT3_SCALE_VEC(normal, approx_normal, scale); } xglNormal3dv(normal); xglTexCoord2f(calc_lon(nodes[n4][0], nodes[n4][1], nodes[n4][2]), calc_lat(nodes[n4][0], nodes[n4][1], nodes[n4][2])); xglVertex3d(nodes[n4][0], nodes[n4][1], nodes[n4][2]); odd = 1 - odd; last1 = n3; last2 = n4; } } else if ( line[0] == 'f' ) { /* unoptimized face */ if ( !first ) { /* close out the previous structure and start the next */ xglEnd(); } else { first = 0; } xglBegin(GL_TRIANGLES); /* fgPrintf( FG_TERRAIN, FG_DEBUG, "new triangle = %s", line);*/ sscanf(line, "f %d %d %d\n", &n1, &n2, &n3); xglNormal3d(normals[n1][0], normals[n1][1], normals[n1][2]); xglTexCoord2f(calc_lon(nodes[n1][0], nodes[n1][1], nodes[n1][2]), calc_lat(nodes[n1][0], nodes[n1][1], nodes[n1][2])); xglVertex3d(nodes[n1][0], nodes[n1][1], nodes[n1][2]); xglNormal3d(normals[n2][0], normals[n2][1], normals[n2][2]); xglTexCoord2f(calc_lon(nodes[n2][0], nodes[n2][1], nodes[n2][2]), calc_lat(nodes[n2][0], nodes[n2][1], nodes[n2][2])); xglVertex3d(nodes[n2][0], nodes[n2][1], nodes[n2][2]); xglNormal3d(normals[n3][0], normals[n3][1], normals[n3][2]); xglTexCoord2f(calc_lon(nodes[n3][0], nodes[n3][1], nodes[n3][2]), calc_lat(nodes[n3][0], nodes[n3][1], nodes[n3][2])); xglVertex3d(nodes[n3][0], nodes[n3][1], nodes[n3][2]); } else if ( line[0] == 'q' ) { /* continue a triangle strip */ n1 = n2 = 0; /* fgPrintf( FG_TERRAIN, FG_DEBUG, "continued tri strip = %s ", line); */ sscanf(line, "q %d %d\n", &n1, &n2); /* fgPrintf( FG_TERRAIN, FG_DEBUG, "read %d %d\n", n1, n2); */ if ( use_per_vertex_norms ) { MAT3_SCALE_VEC(normal, normals[n1], scale); xglNormal3dv(normal); } else { if ( odd ) { calc_normal(nodes[last1], nodes[last2], nodes[n1], approx_normal); } else { calc_normal(nodes[last2], nodes[last1], nodes[n1], approx_normal); } MAT3_SCALE_VEC(normal, approx_normal, scale); xglNormal3dv(normal); } xglTexCoord2f(calc_lon(nodes[n1][0], nodes[n1][1], nodes[n1][2]), calc_lat(nodes[n1][0], nodes[n1][1], nodes[n1][2])); xglVertex3d(nodes[n1][0], nodes[n1][1], nodes[n1][2]); odd = 1 - odd; last1 = last2; last2 = n1; if ( n2 > 0 ) { /* fgPrintf( FG_TERRAIN, FG_DEBUG, " (cont)\n"); */ if ( use_per_vertex_norms ) { MAT3_SCALE_VEC(normal, normals[n2], scale); xglNormal3dv(normal); } else { if ( odd ) { calc_normal(nodes[last1], nodes[last2], nodes[n2], approx_normal); } else { calc_normal(nodes[last2], nodes[last1], nodes[n2], approx_normal); } MAT3_SCALE_VEC(normal, approx_normal, scale); xglNormal3dv(normal); } xglTexCoord2f(calc_lon(nodes[n2][0], nodes[n2][1], nodes[n2][2]), calc_lat(nodes[n2][0], nodes[n2][1], nodes[n2][2])); xglVertex3d(nodes[n2][0], nodes[n2][1], nodes[n2][2]); odd = 1 -odd; last1 = last2; last2 = n2; } } else { fgPrintf( FG_TERRAIN, FG_WARN, "Unknown line in %s = %s\n", path, line); } } xglEnd(); /* Draw normal vectors (for visually verifying normals)*/ /* xglBegin(GL_LINES); xglColor3f(0.0, 0.0, 0.0); for ( i = 0; i < ncount; i++ ) { xglVertex3d(nodes[i][0], nodes[i][1] , nodes[i][2]); xglVertex3d(nodes[i][0] + 500*normals[i][0], nodes[i][1] + 500*normals[i][1], nodes[i][2] + 500*normals[i][2]); } xglEnd(); */ // xglDisable(GL_TEXTURE_GEN_S); // xglDisable(GL_TEXTURE_GEN_T); xglFrontFace ( GL_CCW ); xglEndList(); fclose(f); /* reference point is the "center" */ ref->x = (xmin + xmax) / 2.0; ref->y = (ymin + ymax) / 2.0; ref->z = (zmin + zmax) / 2.0; return(tile); } /* $Log$ /* Revision 1.26 1998/04/03 22:11:36 curt /* Converting to Gnu autoconf system. /* * Revision 1.25 1998/03/14 00:30:50 curt * Beginning initial terrain texturing experiments. * * Revision 1.24 1998/02/09 21:30:18 curt * Fixed a nagging problem with terrain tiles not "quite" matching up perfectly. * * Revision 1.23 1998/02/09 15:07:52 curt * Minor tweaks. * * Revision 1.22 1998/02/01 03:39:54 curt * Minor tweaks. * * Revision 1.21 1998/01/31 00:43:25 curt * Added MetroWorks patches from Carmen Volpe. * * Revision 1.20 1998/01/29 00:51:39 curt * First pass at tile cache, dynamic tile loading and tile unloading now works. * * Revision 1.19 1998/01/27 03:26:42 curt * Playing with new fgPrintf command. * * Revision 1.18 1998/01/19 19:27:16 curt * Merged in make system changes from Bob Kuehne * This should simplify things tremendously. * * Revision 1.17 1998/01/13 00:23:10 curt * Initial changes to support loading and management of scenery tiles. Note, * there's still a fair amount of work left to be done. * * Revision 1.16 1997/12/30 23:09:40 curt * Worked on winding problem without luck, so back to calling glFrontFace() * 3 times for each scenery area. * * Revision 1.15 1997/12/30 20:47:51 curt * Integrated new event manager with subsystem initializations. * * Revision 1.14 1997/12/30 01:38:46 curt * Switched back to per vertex normals and smooth shading for terrain. * * Revision 1.13 1997/12/18 23:32:36 curt * First stab at sky dome actually starting to look reasonable. :-) * * Revision 1.12 1997/12/17 23:13:47 curt * Began working on rendering the sky. * * Revision 1.11 1997/12/15 23:55:01 curt * Add xgl wrappers for debugging. * Generate terrain normals on the fly. * * Revision 1.10 1997/12/12 21:41:28 curt * More light/material property tweaking ... still a ways off. * * Revision 1.9 1997/12/12 19:52:57 curt * Working on lightling and material properties. * * Revision 1.8 1997/12/10 01:19:51 curt * Tweaks for verion 0.15 release. * * Revision 1.7 1997/12/08 22:51:17 curt * Enhanced to handle ccw and cw tri-stripe winding. This is a temporary * admission of defeat. I will eventually go back and get all the stripes * wound the same way (ccw). * * Revision 1.6 1997/11/25 19:25:35 curt * Changes to integrate Durk's moon/sun code updates + clean up. * * Revision 1.5 1997/11/15 18:16:39 curt * minor tweaks. * * Revision 1.4 1997/11/14 00:26:49 curt * Transform scenery coordinates earlier in pipeline when scenery is being * created, not when it is being loaded. Precalculate normals for each node * as average of the normals of each containing polygon so Garoude shading is * now supportable. * * Revision 1.3 1997/10/31 04:49:12 curt * Tweaking vertex orders. * * Revision 1.2 1997/10/30 12:38:45 curt * Working on new scenery subsystem. * * Revision 1.1 1997/10/28 21:14:54 curt * Initial revision. * */