-/**************************************************************************
- * 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 <stdio.h>
-#include <string.h>
-
-#include "obj.h"
-
-#include <Math/mat3.h>
-
-
-/* what do ya' know, here's some global variables */
-static double nodes[MAXNODES][3];
-static double normals[MAXNODES][3];
-static int faces[MAXNODES][3];
-int ncount, vncount, fcount;
-
-static int ccw_list[MAXNODES];
-int ccw_list_ptr;
-
-static int cw_list[MAXNODES];
-int cw_list_ptr;
-
-FILE *in, *out;
-
-double refx, refy, refz;
-
-
-/* some simple list routines */
-
-/* reset the list */
-void list_init(int *list_ptr) {
- *list_ptr = 0;
-}
-
-
-/* add to list */
-void list_add(int *list, int *list_ptr, int node) {
- if ( *list_ptr >= MAXNODES ) {
- printf("ERROR: list overflow in list_add()\n");
- exit(-1);
- }
-
- list[*list_ptr] = node;
- *list_ptr += 1;
-
- /* printf("list pointer = %d adding %d\n", *list_ptr, node); */
-}
-
-
-/* fix the cw list and append to ccw_list */
-void fix_cw_list(int *list, int list_ptr) {
- int i, j, len;
-
- if ( list_ptr < 3 ) {
- printf("List is empty ... skipping\n");
- return;
- }
-
- printf("Fixing cw list, size = %d\n", list_ptr);
-
- i = 0;
- while ( i < list_ptr ) {
- /* do next strip */
-
- /* find length */
- len = 0;
- /* scan rest of strip (until -1) */
- while ( ((i+len) < list_ptr) && (list[i+len] != -1) ) {
- // printf("len = %d item = %d\n", len, list[i+len] );
- len++;
- }
- // printf(" Final length = %d\n", len);
-
- if ( (len % 2) != 0 ) {
- /* if length is odd, just reverse order of nodes to reverse
- winding */
- if ( ccw_list_ptr ) {
- list_add(ccw_list, &ccw_list_ptr, -1);
- }
- for ( j = i + len - 1; j >= i; j-- ) {
- // printf(" odd -> item = %d\n", list[j] );
- list_add(ccw_list, &ccw_list_ptr, list[j]);
- }
- } else {
- /* if length is even, reverse order of (n-1) nodes to
- reverse winding, and create an orphan triangle for the
- last "nth" node */
- if ( ccw_list_ptr ) {
- list_add(ccw_list, &ccw_list_ptr, -1);
- }
- for ( j = i + len - 2; j >= i; j-- ) {
- // printf(" even -> item = %d\n", list[j] );
- list_add(ccw_list, &ccw_list_ptr, list[j]);
- }
-
- // printf(" even bonus -> item = %d\n", list[i + len - 1] );
- // printf(" even bonus -> item = %d\n", list[i + len - 2] );
- // printf(" even bonus -> item = %d\n", list[i + len - 3] );
- list_add(ccw_list, &ccw_list_ptr, -1);
- list_add(ccw_list, &ccw_list_ptr, list[i + len - 3]);
- list_add(ccw_list, &ccw_list_ptr, list[i + len - 2]);
- list_add(ccw_list, &ccw_list_ptr, list[i + len - 1]);
- }
-
- i += len + 1;
- }
-}
-
-
-// Calculate distance between (0,0,0) and the specified point
-static double calc_dist(double x, double y, double z) {
- return ( sqrt(x*x + y*y + z*z) );
-}
-
-
-void dump_global_bounds( void ) {
- double dist, radius;
- int i;
-
- radius = 0.0;
-
- fprintf(out, "\n");
-
- for ( i = 1; i < ncount; i++ ) {
-
- dist = calc_dist(nodes[i][0] - refx, nodes[i][1] - refy,
- nodes[i][2] - refz);
- // printf("node = %.2f %.2f %.2f dist = %.2f\n",
- // nodes[i][0], nodes[i][1], nodes[i][2],
- // dist);
-
- if ( dist > radius ) {
- radius = dist;
- }
-
- }
-
- fprintf(out, "gbs %.5f %.5f %.5f %.2f\n", refx, refy, refz, radius);
-}
-
-
-/* dump nodes */
-void dump_nodes( void ) {
- int i;
-
- fprintf(out, "\n");
- for ( i = 1; i < ncount; i++ ) {
- fprintf(out, "v %.5f %.5f %.5f\n",
- nodes[i][0] - refx, nodes[i][1] - refy, nodes[i][2] - refz);
- }
-}
-
-
-/* dump normals */
-void dump_normals( void ) {
- int i;
-
- fprintf(out, "\n");
- for ( i = 1; i < vncount; i++ ) {
- fprintf(out, "vn %.5f %.5f %.5f\n",
- normals[i][0], normals[i][1], normals[i][2]);
- }
-}
-
-
-/* dump faces */
-void dump_faces( void ) {
- int i, n1, n2, n3;
- double x, y, z, xmax, xmin, ymax, ymin, zmax, zmin, dist, radius;
-
- fprintf(out, "\n");
- for ( i = 1; i < fcount; i++ ) {
- n1 = faces[i][0];
- n2 = faces[i][1];
- n3 = faces[i][2];
-
- /* calc center of face */
- xmin = xmax = nodes[n1][0];
- ymin = ymax = nodes[n1][1];
- zmin = zmax = nodes[n1][2];
-
- if ( nodes[n2][0] < xmin ) { xmin = nodes[n2][0]; }
- if ( nodes[n2][0] > xmax ) { xmax = nodes[n2][0]; }
- if ( nodes[n2][1] < ymin ) { ymin = nodes[n2][1]; }
- if ( nodes[n2][1] > ymax ) { ymax = nodes[n2][1]; }
- if ( nodes[n2][2] < zmin ) { zmin = nodes[n2][2]; }
- if ( nodes[n2][2] > zmax ) { zmax = nodes[n2][2]; }
-
- if ( nodes[n3][0] < xmin ) { xmin = nodes[n3][0]; }
- if ( nodes[n3][0] > xmax ) { xmax = nodes[n3][0]; }
- if ( nodes[n3][1] < ymin ) { ymin = nodes[n3][1]; }
- if ( nodes[n3][1] > ymax ) { ymax = nodes[n3][1]; }
- if ( nodes[n3][2] < zmin ) { zmin = nodes[n3][2]; }
- if ( nodes[n3][2] > zmax ) { zmax = nodes[n3][2]; }
-
- x = (xmin + xmax) / 2.0;
- y = (ymin + ymax) / 2.0;
- z = (zmin + zmax) / 2.0;
-
- /* calc bounding radius */
- radius = calc_dist(nodes[n1][0] - x, nodes[n1][1] - y,
- nodes[n1][2] - z);
-
- dist = calc_dist(nodes[n2][0] - x, nodes[n2][1] - y, nodes[n2][2] - z);
- if ( dist > radius ) { radius = dist; }
-
- dist = calc_dist(nodes[n3][0] - x, nodes[n3][1] - y, nodes[n3][2] - z);
- if ( dist > radius ) { radius = dist; }
-
- /* output data */
- fprintf(out, "bs %.2f %.2f %.2f %.2f\n", x, y, z, radius);
- fprintf(out, "f %d %d %d\n", n1, n2, n3);
- }
-}
-
-
-/* dump list */
-void dump_list(int *list, int list_ptr) {
- double x, y, z, xmax, xmin, ymax, ymin, zmax, zmin, dist, radius;
- int i, j, len, n;
-
- if ( list_ptr < 3 ) {
- printf("List is empty ... skipping\n");
- return;
- }
-
- printf("Dumping list, size = %d\n", list_ptr);
-
- i = 0;
- while ( i < list_ptr ) {
- /* do next strip */
-
- if ( (i % 2) == 0 ) {
- fprintf(out, "\nusemtl desert1\n");
- } else {
- fprintf(out, "\nusemtl desert2\n");
- }
-
- /* find length of next tri strip */
- len = 0;
- /* scan rest of strip (until -1) */
- while ( ((i+len) < list_ptr) && (list[i+len] != -1) ) {
- // printf("len = %d item = %d\n", len, list[i+len] );
- len++;
- }
- // printf("strip length = %d\n", len);
-
- /* calc center of face */
- n = list[i];
- xmin = xmax = nodes[n][0];
- ymin = ymax = nodes[n][1];
- zmin = zmax = nodes[n][2];
- // printf("%.2f %.2f %.2f\n", nodes[n][0], nodes[n][1], nodes[n][2]);
-
- for ( j = i + 1; j < i + len; j++ ) {
- // printf("j = %d\n", j);
- n = list[j];
- if ( nodes[n][0] < xmin ) { xmin = nodes[n][0]; }
- if ( nodes[n][0] > xmax ) { xmax = nodes[n][0]; }
- if ( nodes[n][1] < ymin ) { ymin = nodes[n][1]; }
- if ( nodes[n][1] > ymax ) { ymax = nodes[n][1]; }
- if ( nodes[n][2] < zmin ) { zmin = nodes[n][2]; }
- if ( nodes[n][2] > zmax ) { zmax = nodes[n][2]; }
- // printf("%.2f %.2f %.2f\n", nodes[n][0], nodes[n][1], nodes[n][2]);
- }
- x = (xmin + xmax) / 2.0;
- y = (ymin + ymax) / 2.0;
- z = (zmin + zmax) / 2.0;
- // printf("center = %.2f %.2f %.2f\n", x, y, z);
-
- /* calc bounding radius */
- n = list[i];
- radius = calc_dist(nodes[n][0] - x, nodes[n][1] - y, nodes[n][2] - z);
-
- for ( j = i + 1; j < i + len; j++ ) {
- n = list[j];
- dist = calc_dist(nodes[n][0] - x, nodes[n][1] - y,
- nodes[n][2] - z);
- if ( dist > radius ) { radius = dist; }
- }
- // printf("radius = %.2f\n", radius);
-
- /* dump bounding sphere and header */
- fprintf(out, "bs %.2f %.2f %.2f %.2f\n", x, y, z, radius);
- fprintf(out, "t %d %d %d\n", list[i], list[i+1], list[i+2]);
- /* printf("t %d %d %d\n", list[i], list[i+1], list[i+2]); */
- i += 3;
-
- /* dump rest of strip (until -1) */
- while ( (i < list_ptr) && (list[i] != -1) ) {
- fprintf(out, "q %d", list[i]);
- i++;
- if ( (i < list_ptr) && (list[i] != -1) ) {
- fprintf(out, " %d", list[i]);
- i++;
- }
- fprintf(out, "\n");
- }
-
- i++;
- }
-}
-
-
-/* Check the direction the current triangle faces, compared to it's
- * pregenerated normal. Returns the dot product between the target
- * normal and actual normal. If the dot product is close to 1.0, they
- * nearly match. If the are close to -1.0, the are nearly
- * opposite. */
-double check_cur_face(int n1, int n2, int n3) {
- double v1[3], v2[3], approx_normal[3], dot_prod, temp;
-
- /* check for the proper rotation by calculating an approximate
- * normal and seeing if it is close to the precalculated normal */
- v1[0] = nodes[n2][0] - nodes[n1][0];
- v1[1] = nodes[n2][1] - nodes[n1][1];
- v1[2] = nodes[n2][2] - nodes[n1][2];
- v2[0] = nodes[n3][0] - nodes[n1][0];
- v2[1] = nodes[n3][1] - nodes[n1][1];
- v2[2] = nodes[n3][2] - nodes[n1][2];
-
- MAT3cross_product(approx_normal, v1, v2);
- MAT3_NORMALIZE_VEC(approx_normal,temp);
- dot_prod = MAT3_DOT_PRODUCT(normals[n1], approx_normal);
-
- /* not first triangle */
- /* if ( ((dot_prod < -0.5) && !is_backwards) ||
- ((dot_prod > 0.5) && is_backwards) ) {
- printf(" Approx normal = %.2f %.2f %.2f\n", approx_normal[0],
- approx_normal[1], approx_normal[2]);
- printf(" Dot product = %.4f\n", dot_prod);
- } */
- /* angle = acos(dot_prod); */
- /* printf("Normal ANGLE = %.3f rads.\n", angle); */
-
- return(dot_prod);
-}
-
-
-/* Load a .obj file */
-void obj_fix(char *infile, char *outfile) {
- char line[256];
- double dot_prod;
- int first, n1, n2, n3, n4;
- double x, y, z, xmax, xmin, ymax, ymin, zmax, zmin;
- int is_ccw;
-
- if ( (in = fopen(infile, "r")) == NULL ) {
- printf("Cannot open file: %s\n", infile);
- exit(-1);
- }
-
- if ( (out = fopen(outfile, "w")) == NULL ) {
- printf("Cannot open file: %s\n", outfile);
- exit(-1);
- }
-
- list_init(&ccw_list_ptr);
- list_init(&cw_list_ptr);
-
- /* I start counting at one because that is how the triangle
- program refers to nodes and normals */
- first = 1;
- ncount = 1;
- vncount = 1;
- fcount = 1;
-
- printf("Reading file: %s\n", infile);
-
- while ( fgets(line, 250, in) != NULL ) {
- if ( line[0] == '#' ) {
- /* pass along the comments verbatim */
- fprintf(out, "%s", line);
- } else if ( strlen(line) <= 1 ) {
- /* don't pass along empty lines */
- // fprintf(out, "%s", line);
- } else if ( strncmp(line, "v ", 2) == 0 ) {
- /* save vertex to memory and output to file */
- if ( ncount < MAXNODES ) {
- /* printf("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;
-
- // fprintf(out, "v %.2f %.2f %.2f\n",
- // nodes[ncount][0], nodes[ncount][1], nodes[ncount][2]);
- ncount++;
- } else {
- printf("Read too many nodes ... dying :-(\n");
- exit(-1);
- }
- } else if ( strncmp(line, "vn ", 3) == 0 ) {
- /* save vertex normals to memory and output to file */
- if ( vncount < MAXNODES ) {
- /* printf("vertex normal = %s", line); */
- sscanf(line, "vn %lf %lf %lf\n",
- &normals[vncount][0], &normals[vncount][1],
- &normals[vncount][2]);
- // fprintf(out, "vn %.4f %.4f %.4f\n", normals[vncount][0],
- // normals[vncount][1], normals[vncount][2]);
- vncount++;
- } else {
- printf("Read too many vertex normals ... dying :-(\n");
- exit(-1);
- }
- } else if ( line[0] == 't' ) {
- /* starting a new triangle strip */
-
- printf("Starting a new triangle strip\n");
-
- n1 = n2 = n3 = n4 = 0;
-
- printf("new tri strip = %s", line);
- sscanf(line, "t %d %d %d %d\n", &n1, &n2, &n3, &n4);
-
- /* special cases to handle bugs in our beloved tri striper */
- if ( (n1 == 4) && (n2 == 2) && (n3 == 2) && (n4 == 1) ) {
- n2 = 3;
- }
- if ( (n1 == 3) && (n2 == 1) && (n3 == 1) && (n4 == 0) ) {
- n3 = 4;
- }
-
- dot_prod = check_cur_face(n1, n2, n3);
- if ( dot_prod < 0.0 ) {
- /* this stripe is backwards (CW) */
- is_ccw = 0;
- printf(" -> Starting a backwards stripe\n");
- } else {
- /* this stripe is normal (CCW) */
- is_ccw = 1;
- }
-
- if ( is_ccw ) {
- if ( ccw_list_ptr ) {
- list_add(ccw_list, &ccw_list_ptr, -1);
- }
-
- list_add(ccw_list, &ccw_list_ptr, n1);
- list_add(ccw_list, &ccw_list_ptr, n2);
- list_add(ccw_list, &ccw_list_ptr, n3);
- } else {
- if ( cw_list_ptr ) {
- list_add(cw_list, &cw_list_ptr, -1);
- }
-
- list_add(cw_list, &cw_list_ptr, n1);
- list_add(cw_list, &cw_list_ptr, n2);
- list_add(cw_list, &cw_list_ptr, n3);
- }
-
- if ( n4 > 0 ) {
- if ( is_ccw ) {
- list_add(ccw_list, &ccw_list_ptr, n4);
- } else {
- list_add(cw_list, &cw_list_ptr, n4);
- }
- }
- } else if ( line[0] == 'f' ) {
- if ( fcount < MAXNODES ) {
- /* pass along the unoptimized faces verbatim */
- sscanf(line, "f %d %d %d\n", &n1, &n2, &n3);
- faces[fcount][0] = n1;
- faces[fcount][1] = n2;
- faces[fcount][2] = n3;
-
- fcount++;
- } else {
- printf("Read too many unoptimized faces ... dying :-(\n");
- exit(-1);
- }
-
- // fprintf(out, "%s", line);
- } else if ( line[0] == 'q' ) {
- /* continue a triangle strip */
- n1 = n2 = 0;
-
- /* printf("continued tri strip = %s ", line); */
- sscanf(line, "q %d %d\n", &n1, &n2);
-
- if ( is_ccw ) {
- list_add(ccw_list, &ccw_list_ptr, n1);
- } else {
- list_add(cw_list, &cw_list_ptr, n1);
- }
-
- if ( n2 > 0 ) {
- if ( is_ccw ) {
- list_add(ccw_list, &ccw_list_ptr, n2);
- } else {
- list_add(cw_list, &cw_list_ptr, n2);
- }
- }
- } else {
- printf("Unknown line in %s = %s\n", infile, line);
- }
- }
-
- /* reference point is the "center" */
- refx = (xmin + xmax) / 2.0;
- refy = (ymin + ymax) / 2.0;
- refz = (zmin + zmax) / 2.0;
-
- /* convert the cw_list to ccw add append to ccw_list */
- fix_cw_list(cw_list, cw_list_ptr);
-
- dump_global_bounds();
- dump_nodes();
- dump_normals();
- if ( fcount > 1 ) {
- dump_faces();
- }
-
- dump_list(ccw_list, ccw_list_ptr);
-
- fclose(in);
- fclose(out);
-}
-
-
-/* $Log$
-/* Revision 1.16 1998/05/27 02:27:22 curt
-/* Commented out a couple of debugging messages.
-/*
- * Revision 1.15 1998/05/24 02:47:47 curt
- * For each strip, specify a default material property and calculate a center
- * and bounding sphere.
- *
- * Revision 1.14 1998/05/23 15:19:49 curt
- * Output more digits after the decimal place.
- *
- * Revision 1.13 1998/05/20 20:55:19 curt
- * Fixed arbitrary polygon winding problem here so all tristrips are passed
- * to runtime simulator with a consistant counter clockwise winding.
- *
- * Revision 1.12 1998/05/16 13:11:26 curt
- * Fixed an off by one error in node, normal, and face counters.
- *
- * Revision 1.11 1998/04/27 15:59:24 curt
- * Fixed an off by one error.
- *
- * Revision 1.10 1998/04/27 03:33:11 curt
- * Code now calculates a center reference points and outputs everything
- * relative to that. This is useful in the rendering engine to keep everything
- * close to (0, 0, 0) where we can avoid many GLfloat precision problems.
- *
- * Revision 1.9 1998/04/18 04:01:03 curt
- * Now use libMath rather than having local copies of math routines.
- *
- * Revision 1.8 1998/04/08 23:19:37 curt
- * Adopted Gnu automake/autoconf system.
- *
- * Revision 1.7 1998/03/19 02:51:41 curt
- * Added special case handling to compensate for bugs in our beloved tri striper
- *
- * Revision 1.6 1998/03/03 15:36:12 curt
- * Tweaks for compiling with g++
- *
- * Revision 1.5 1998/03/03 03:37:03 curt
- * Cumulative tweaks.
- *
- * Revision 1.4 1998/01/31 00:41:25 curt
- * Made a few changes converting floats to doubles.
- *
- * Revision 1.3 1998/01/19 19:51:07 curt
- * A couple final pre-release tweaks.
- *
- * Revision 1.2 1998/01/09 23:03:12 curt
- * Restructured to split 1deg x 1deg dem's into 64 subsections.
- *
- * Revision 1.1 1997/12/08 19:28:54 curt
- * Initial revision.
- *
- */