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flightgear/Tri2obj/tri2obj.cxx
1998-10-21 14:56:50 +00:00

695 lines
19 KiB
C++

// tri2obj.cxx -- read in a .ele/.node file pair generated by the triangle
// program and output a simple Wavefront .obj file.
//
// 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 <stdlib.h> // for atoi()
#include <string.h>
#include <sys/stat.h> // for stat()
#include <unistd.h> // for stat()
#include "tri2obj.hxx"
#include <Include/fg_constants.h>
#include <Bucket/bucketutils.h>
#include <Math/fg_geodesy.hxx>
#include <Math/mat3.h>
#include <Math/polar3d.hxx>
int nodecount, tricount;
int normalcount = 0;
static Point3D nodes[MAX_NODES];
static int tris[MAX_TRIS][3];
static double normals[MAX_NODES][3];
fgBUCKET my_index;
fgBUCKET ne_index, nw_index, sw_index, se_index;
fgBUCKET north_index, south_index, east_index, west_index;
// given three points defining a triangle, calculate the normal
void calc_normal(const Point3D& p1, const Point3D& p2,
const Point3D& p3, double normal[3])
{
double v1[3], v2[3];
double temp;
v1[0] = p2.x() - p1.x(); v1[1] = p2.y() - p1.y(); v1[2] = p2.z() - p1.z();
v2[0] = p3.x() - p1.x(); v2[1] = p3.y() - p1.y(); v2[2] = p3.z() - p1.z();
MAT3cross_product(normal, v1, v2);
MAT3_NORMALIZE_VEC(normal, temp);
// printf(" Normal = %.2f %.2f %.2f\n", normal[0], normal[1], normal[2]);
}
// return the index of all triangles containing the specified node
void find_tris(int n, int *t1, int *t2, int *t3, int *t4, int *t5) {
int i;
*t1 = *t2 = *t3 = *t4 = *t5 = 0;
i = 1;
while ( i <= tricount ) {
if ( (n == tris[i][0]) || (n == tris[i][1]) || (n == tris[i][2]) ) {
if ( *t1 == 0 ) {
*t1 = i;
} else if ( *t2 == 0 ) {
*t2 = i;
} else if ( *t3 == 0 ) {
*t3 = i;
} else if ( *t4 == 0 ) {
*t4 = i;
} else {
*t5 = i;
}
}
i++;
}
}
// return the file base name ( foo/bar/file.ext = file.ext )
void extract_file(char *in, char *base) {
int len, i;
len = strlen(in);
i = len - 1;
while ( (i >= 0) && (in[i] != '/') ) {
i--;
}
in += (i + 1);
strcpy(base, in);
}
// return the file path name ( foo/bar/file.ext = foo/bar )
void extract_path(char *in, char *base) {
int len, i;
len = strlen(in);
strcpy(base, in);
i = len - 1;
while ( (i >= 0) && (in[i] != '/') ) {
i--;
}
base[i] = '\0';
}
// check if a file exists
int file_exists(char *file) {
struct stat stat_buf;
int result;
printf("checking %s ... ", file);
result = stat(file, &stat_buf);
if ( result != 0 ) {
// stat failed, no file
printf("not found.\n");
return(0);
} else {
// stat succeeded, file exists
printf("exists.\n");
return(1);
}
}
// check to see if a shared object exists
int shared_object_exists(char *basepath, char *ext, char *file) {
char scene_path[256];
long int index;
if ( strcmp(ext, ".sw") == 0 ) {
fgBucketGenBasePath(&my_index, scene_path);
index = fgBucketGenIndex(&my_index);
sprintf(file, "%s/%s/%ld.1.sw", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&west_index, scene_path);
index = fgBucketGenIndex(&west_index);
sprintf(file, "%s/%s/%ld.1.se", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&sw_index, scene_path);
index = fgBucketGenIndex(&sw_index);
sprintf(file, "%s/%s/%ld.1.ne", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&south_index, scene_path);
index = fgBucketGenIndex(&south_index);
sprintf(file, "%s/%s/%ld.1.nw", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
}
if ( strcmp(ext, ".se") == 0 ) {
fgBucketGenBasePath(&my_index, scene_path);
index = fgBucketGenIndex(&my_index);
sprintf(file, "%s/%s/%ld.1.se", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&east_index, scene_path);
index = fgBucketGenIndex(&east_index);
sprintf(file, "%s/%s/%ld.1.sw", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&se_index, scene_path);
index = fgBucketGenIndex(&se_index);
sprintf(file, "%s/%s/%ld.1.nw", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&south_index, scene_path);
index = fgBucketGenIndex(&south_index);
sprintf(file, "%s/%s/%ld.1.ne", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
}
if ( strcmp(ext, ".ne") == 0 ) {
fgBucketGenBasePath(&my_index, scene_path);
index = fgBucketGenIndex(&my_index);
sprintf(file, "%s/%s/%ld.1.ne", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&east_index, scene_path);
index = fgBucketGenIndex(&east_index);
sprintf(file, "%s/%s/%ld.1.nw", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&ne_index, scene_path);
index = fgBucketGenIndex(&ne_index);
sprintf(file, "%s/%s/%ld.1.sw", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&north_index, scene_path);
index = fgBucketGenIndex(&north_index);
sprintf(file, "%s/%s/%ld.1.se", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
}
if ( strcmp(ext, ".nw") == 0 ) {
fgBucketGenBasePath(&my_index, scene_path);
index = fgBucketGenIndex(&my_index);
sprintf(file, "%s/%s/%ld.1.nw", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&west_index, scene_path);
index = fgBucketGenIndex(&west_index);
sprintf(file, "%s/%s/%ld.1.ne", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&nw_index, scene_path);
index = fgBucketGenIndex(&nw_index);
sprintf(file, "%s/%s/%ld.1.se", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&north_index, scene_path);
index = fgBucketGenIndex(&north_index);
sprintf(file, "%s/%s/%ld.1.sw", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
}
if ( strcmp(ext, ".south") == 0 ) {
fgBucketGenBasePath(&my_index, scene_path);
index = fgBucketGenIndex(&my_index);
sprintf(file, "%s/%s/%ld.1.south", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&south_index, scene_path);
index = fgBucketGenIndex(&south_index);
sprintf(file, "%s/%s/%ld.1.north", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
}
if ( strcmp(ext, ".north") == 0 ) {
fgBucketGenBasePath(&my_index, scene_path);
index = fgBucketGenIndex(&my_index);
sprintf(file, "%s/%s/%ld.1.north", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&north_index, scene_path);
index = fgBucketGenIndex(&north_index);
sprintf(file, "%s/%s/%ld.1.south", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
}
if ( strcmp(ext, ".west") == 0 ) {
fgBucketGenBasePath(&my_index, scene_path);
index = fgBucketGenIndex(&my_index);
sprintf(file, "%s/%s/%ld.1.west", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&west_index, scene_path);
index = fgBucketGenIndex(&west_index);
sprintf(file, "%s/%s/%ld.1.east", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
}
if ( strcmp(ext, ".east") == 0 ) {
fgBucketGenBasePath(&my_index, scene_path);
index = fgBucketGenIndex(&my_index);
sprintf(file, "%s/%s/%ld.1.east", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
fgBucketGenBasePath(&east_index, scene_path);
index = fgBucketGenIndex(&east_index);
sprintf(file, "%s/%s/%ld.1.west", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
}
if ( strcmp(ext, ".body") == 0 ) {
fgBucketGenBasePath(&my_index, scene_path);
index = fgBucketGenIndex(&my_index);
sprintf(file, "%s/%s/%ld.1.body", basepath, scene_path, index);
if ( file_exists(file) ) {
return(1);
}
}
return(0);
}
// given a file pointer, read all the vn (normals from it)
void read_normals(FILE *fp) {
char line[256];
while ( fgets(line, 250, fp) != NULL ) {
if ( strncmp(line, "vn ", 3) == 0 ) {
sscanf( line, "vn %lf %lf %lf\n",
&normals[normalcount][0],
&normals[normalcount][1],
&normals[normalcount][2] );
/*
printf("read_normals(%d) %.2f %.2f %.2f %s", normalcount,
normals[normalcount][0], normals[normalcount][1],
normals[normalcount][2], line);
*/
normalcount++;
}
}
}
// my custom file opening routine ... don't open if a shared edge or
// vertex alread exists
FILE *my_open(char *basename, char *basepath, char *ext) {
FILE *fp;
char filename[256];
// check if a shared object already exists
if ( shared_object_exists(basepath, ext, filename) ) {
// not an actual file open error, but we've already got the
// shared edge, so we don't want to create another one
fp = fopen(filename, "r");
printf("Opening %s\n", filename);
return(fp);
} else {
// open the file
printf("not opening\n");
return(NULL);
}
}
// Initialize a new mesh structure
void triload(char *basename, char *basepath) {
char nodename[256], elename[256];
double n[3];
Point3D p;
FILE *ne, *nw, *se, *sw, *north, *south, *east, *west;
FILE *node, *ele;
int dim, junk1, junk2;
int i;
ne = my_open(basename, basepath, ".ne");
read_normals(ne);
fclose(ne);
nw = my_open(basename, basepath, ".nw");
read_normals(nw);
fclose(nw);
se = my_open(basename, basepath, ".se");
read_normals(se);
fclose(se);
sw = my_open(basename, basepath, ".sw");
read_normals(sw);
fclose(sw);
north = my_open(basename, basepath, ".north");
read_normals(north);
fclose(north);
south = my_open(basename, basepath, ".south");
read_normals(south);
fclose(south);
east = my_open(basename, basepath, ".east");
read_normals(east);
fclose(east);
west = my_open(basename, basepath, ".west");
read_normals(west);
fclose(west);
strcpy(nodename, basename);
strcat(nodename, ".node");
strcpy(elename, basename);
strcat(elename, ".ele");
printf("Loading node file: %s ...\n", nodename);
if ( (node = fopen(nodename, "r")) == NULL ) {
printf("Cannot open file '%s'\n", nodename);
exit(-1);
}
fscanf(node, "%d %d %d %d", &nodecount, &dim, &junk1, &junk2);
if ( nodecount > MAX_NODES - 1 ) {
printf("Error, too many nodes, need to increase array size\n");
exit(-1);
} else {
printf(" Expecting %d nodes\n", nodecount);
}
for ( i = 1; i <= nodecount; i++ ) {
fscanf(node, "%d %lf %lf %lf %d\n", &junk1,
&n[0], &n[1], &n[2], &junk2);
// printf("%d %.2f %.2f %.2f\n", junk1, n[0], n[1], n[2]);
p = Point3D( n[0] * ARCSEC_TO_RAD,
n[1] * ARCSEC_TO_RAD,
n[2] );
nodes[i] = fgGeodToCart(p);
// printf("%d %.2f %.2f %.2f\n",
// junk1, nodes[i].x, nodes[i].y, nodes[i].z);
}
fclose(node);
printf("Loading element file: %s ...\n", elename);
if ( (ele = fopen(elename, "r")) == NULL ) {
printf("Cannot open file '%s'\n", elename);
exit(-1);
}
fscanf(ele, "%d %d %d", &tricount, &junk1, &junk2);
if ( tricount > MAX_TRIS - 1 ) {
printf("Error, too many elements, need to increase array size\n");
exit(-1);
} else {
printf(" Expecting %d elements\n", tricount);
}
for ( i = 1; i <= tricount; i++ ) {
fscanf(ele, "%d %d %d %d\n", &junk1,
&tris[i][0], &tris[i][1], &tris[i][2]);
// printf("%d %d %d %d\n", junk1, tris[i][0], tris[i][1], tris[i][2]);*/
}
fclose(ele);
}
// dump in WaveFront .obj format
void dump_obj(char *basename) {
char objname[256];
double n1[3], n2[3], n3[3], n4[3], n5[3], norm[3], temp;
FILE *obj;
int i, t1, t2, t3, t4, t5, count;
double x, y, z;
strcpy(objname, basename);
strcat(objname, ".obj");
printf("Dumping to file: %s ...\n", objname);
obj = fopen(objname, "w");
// dump vertices
printf(" writing vertices\n");
for ( i = 1; i <= nodecount; i++ ) {
x = nodes[i].x();
y = nodes[i].y();
z = nodes[i].z();
fprintf(obj, "v %.6f %.6f %.6f\n", x, y, z);
}
printf(" calculating and writing normals\n");
printf(" First %d normals taken from shared files.\n", normalcount);
// calculate and generate normals
for ( i = 1; i <= nodecount; i++ ) {
if ( i <= normalcount ) {
// use precalculated (shared) normal
norm[0] = normals[i-1][0];
norm[1] = normals[i-1][1];
norm[2] = normals[i-1][2];
} else {
// printf("Finding normal\n");
find_tris(i, &t1, &t2, &t3, &t4, &t5);
n1[0] = n1[1] = n1[2] = 0.0;
n2[0] = n2[1] = n2[2] = 0.0;
n3[0] = n3[1] = n3[2] = 0.0;
n4[0] = n4[1] = n4[2] = 0.0;
n5[0] = n5[1] = n5[2] = 0.0;
count = 1;
calc_normal(nodes[tris[t1][0]], nodes[tris[t1][1]],
nodes[tris[t1][2]], n1);
if ( t2 > 0 ) {
calc_normal(nodes[tris[t2][0]], nodes[tris[t2][1]],
nodes[tris[t2][2]], n2);
count = 2;
}
if ( t3 > 0 ) {
calc_normal(nodes[tris[t3][0]], nodes[tris[t3][1]],
nodes[tris[t3][2]], n3);
count = 3;
}
if ( t4 > 0 ) {
calc_normal(nodes[tris[t4][0]], nodes[tris[t4][1]],
nodes[tris[t4][2]], n4);
count = 4;
}
if ( t5 > 0 ) {
calc_normal(nodes[tris[t5][0]], nodes[tris[t5][1]],
nodes[tris[t5][2]], n5);
count = 5;
}
// printf(" norm[2] = %.2f %.2f %.2f\n", n1[2], n2[2], n3[2]);
norm[0] = ( n1[0] + n2[0] + n3[0] + n4[0] + n5[0] ) / (double)count;
norm[1] = ( n1[1] + n2[1] + n3[1] + n4[1] + n5[1] ) / (double)count;
norm[2] = ( n1[2] + n2[2] + n3[2] + n4[2] + n5[2] ) / (double)count;
// printf(" count = %d\n", count);
// printf(" Ave. normal = %.4f %.4f %.4f\n",
// norm[0], norm[1], norm[2]);*/
MAT3_NORMALIZE_VEC(norm, temp);
// printf(" Normalized ave. normal = %.4f %.4f %.4f\n",
// norm[0], norm[1], norm[2]);
}
// printf("%d vn %.4f %.4f %.4f\n", i, norm[0], norm[1], norm[2]);
fprintf(obj, "vn %.4f %.4f %.4f\n", norm[0], norm[1], norm[2]);
}
// dump faces
printf(" writing faces\n");
for ( i = 1; i <= tricount; i++ ) {
fprintf(obj, "f %d %d %d\n", tris[i][0], tris[i][1], tris[i][2]);
}
fclose(obj);
}
int main(int argc, char **argv) {
char basename[256], basepath[256], temp[256];
long int tmp_index;
int len;
strcpy(basename, argv[1]);
// find the base path of the file
extract_path(basename, basepath);
extract_path(basepath, basepath);
extract_path(basepath, basepath);
printf("%s\n", basepath);
// find the index of the current file
extract_file(basename, temp);
len = strlen(temp);
if ( len >= 2 ) {
temp[len-2] = '\0';
}
tmp_index = atoi(temp);
printf("%ld\n", tmp_index);
fgBucketParseIndex(tmp_index, &my_index);
printf("bucket = %d %d %d %d\n",
my_index.lon, my_index.lat, my_index.x, my_index.y);
// generate the indexes of the neighbors
fgBucketOffset(&my_index, &ne_index, 1, 1);
fgBucketOffset(&my_index, &nw_index, -1, 1);
fgBucketOffset(&my_index, &se_index, 1, -1);
fgBucketOffset(&my_index, &sw_index, -1, -1);
fgBucketOffset(&my_index, &north_index, 0, 1);
fgBucketOffset(&my_index, &south_index, 0, -1);
fgBucketOffset(&my_index, &east_index, 1, 0);
fgBucketOffset(&my_index, &west_index, -1, 0);
// load the input data files
triload(basename, basepath);
// dump in WaveFront .obj format
dump_obj(basename);
return(0);
}
// $Log$
// Revision 1.5 1998/10/21 14:56:50 curt
// Minor parameter passing tweak.
//
// Revision 1.4 1998/10/20 15:52:46 curt
// Fixed a units conversion bug introduced when converting to Point3D class.
//
// Revision 1.3 1998/10/19 19:33:31 curt
// C++-ification.
//
// Revision 1.2 1998/10/18 01:17:29 curt
// Point3D tweaks.
//
// Revision 1.1 1998/07/08 14:54:53 curt
// renamed *.[ch] to *.[ch]xx
//
// Revision 1.17 1998/07/04 00:56:40 curt
// typedef'd struct fgBUCKET.
//
// Revision 1.16 1998/05/23 15:20:41 curt
// Output more digits after the decimal place.
//
// Revision 1.15 1998/05/02 01:54:39 curt
// Converting to polar3d.h routines.
//
// Revision 1.14 1998/04/18 04:01:32 curt
// Now use libMath rather than having local copies of math routines.
//
// Revision 1.13 1998/04/14 02:26:11 curt
// Code reorganizations. Added a Lib/ directory for more general libraries.
//
// Revision 1.12 1998/04/08 23:22:18 curt
// Adopted Gnu automake/autoconf system.
//
// Revision 1.11 1998/03/03 16:01:00 curt
// More c++ compile tweaks.
//
// Revision 1.10 1998/01/31 00:41:27 curt
// Made a few changes converting floats to doubles.
//
// Revision 1.9 1998/01/27 18:37:04 curt
// Lots of updates to get back in sync with changes made over in .../Src/
//
// Revision 1.8 1998/01/17 01:25:39 curt
// Added support for shared normals.
//
// Revision 1.7 1998/01/12 02:42:00 curt
// Average up to five triangles per vertex instead of three.
//
// Revision 1.6 1998/01/09 23:03:15 curt
// Restructured to split 1deg x 1deg dem's into 64 subsections.
//
// Revision 1.5 1997/12/08 19:17:50 curt
// Fixed a type in the normal generation code.
//
// Revision 1.4 1997/12/02 13:13:32 curt
// Fixed problem with averaged vertex normals.
//
// Revision 1.3 1997/11/15 18:05:05 curt
// minor tweaks ...
//
// Revision 1.2 1997/11/14 00:29:13 curt
// Transform scenery coordinates at this point in pipeline when scenery is
// being translated to .obj format, not when it is being loaded into the end
// renderer. Precalculate normals for each node as average of the normals
// of each containing polygon so Garoude shading is now supportable.
//
// Revision 1.1 1997/10/29 23:05:15 curt
// Initial revision.
//