Quake-III-Arena

trilib.c (5931B)

---

 /*
 ===========================================================================
 Copyright (C) 1999-2005 Id Software, Inc.
 
 This file is part of Quake III Arena source code.
 
 Quake III Arena source code 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.
 
 Quake III Arena source code 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 Foobar; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 ===========================================================================
 */
 //
 // trilib.c: library for loading triangles from an Alias triangle file
 //
 
 #include <stdio.h>
 #include "cmdlib.h"
 #include "mathlib.h"
 #include "polyset.h"
 #include "trilib.h"
 
 // on disk representation of a face
 
 
 #define	FLOAT_START	99999.0
 #define	FLOAT_END	-FLOAT_START
 #define MAGIC       123322
 
 //#define NOISY 1
 
 typedef struct {
 	float v[3];
 } vector;
 
 typedef struct
 {
 	vector n;    /* normal */
 	vector p;    /* point */
 	vector c;    /* color */
 	float  u;    /* u */
 	float  v;    /* v */
 } aliaspoint_t;
 
 typedef struct {
 	aliaspoint_t	pt[3];
 } tf_triangle;
 
 
 static void ByteSwapTri (tf_triangle *tri)
 {
 	int		i;
 	
 	for (i=0 ; i<sizeof(tf_triangle)/4 ; i++)
 	{
 		((int *)tri)[i] = BigLong (((int *)tri)[i]);
 	}
 }
 
 static void ReadPolysetGeometry( triangle_t *tripool, FILE *input, int count, triangle_t *ptri )
 {
 	tf_triangle tri;
 	int i;
 
 	for (i = 0; i < count; ++i) {
 		int		j;
 
 		fread( &tri, sizeof(tf_triangle), 1, input );
 		ByteSwapTri (&tri);
 		for (j=0 ; j<3 ; j++)
 		{
 			int		k;
 
 			for (k=0 ; k<3 ; k++)
 			{
 				ptri->verts[j][k] = tri.pt[j].p.v[k];
 				ptri->normals[j][k] = tri.pt[j].n.v[k];
 //				ptri->colors[j][k] = tri.pt[j].c.v[k];
 			}
 
 			ptri->texcoords[j][0] = tri.pt[j].u;
 			ptri->texcoords[j][1] = tri.pt[j].v;
 		}
 
 		ptri++;
 		if ((ptri - tripool ) >= POLYSET_MAXTRIANGLES)
 			Error ("Error: too many triangles; increase POLYSET_MAXTRIANGLES\n");
 	}
 }
 
 void TRI_LoadPolysets( const char *filename, polyset_t **ppPSET, int *numpsets )
 {
 	FILE        *input;
 	float       start;
 	char        name[256], tex[256];
 	int         i, count, magic, pset = 0;
 	triangle_t	*ptri;
 	polyset_t	*pPSET;
 	int			iLevel;
 	int			exitpattern;
 	float		t;
 
 	t = -FLOAT_START;
 	*((unsigned char *)&exitpattern + 0) = *((unsigned char *)&t + 3);
 	*((unsigned char *)&exitpattern + 1) = *((unsigned char *)&t + 2);
 	*((unsigned char *)&exitpattern + 2) = *((unsigned char *)&t + 1);
 	*((unsigned char *)&exitpattern + 3) = *((unsigned char *)&t + 0);
 
 	if ((input = fopen(filename, "rb")) == 0)
 		Error ("reader: could not open file '%s'", filename);
 
 	iLevel = 0;
 
 	fread(&magic, sizeof(int), 1, input);
 	if (BigLong(magic) != MAGIC)
 		Error ("%s is not a Alias object separated triangle file, magic number is wrong.", filename);
 
 	pPSET = calloc( 1, POLYSET_MAXPOLYSETS * sizeof( polyset_t ) );
 	ptri = calloc( 1, POLYSET_MAXTRIANGLES * sizeof( triangle_t ) );
 
 	*ppPSET = pPSET;
 
 	while (feof(input) == 0) {
 		if (fread(&start,  sizeof(float), 1, input) < 1)
 			break;
 		*(int *)&start = BigLong(*(int *)&start);
 		if (*(int *)&start != exitpattern)
 		{
 			if (start == FLOAT_START) {
 				/* Start of an object or group of objects. */
 				i = -1;
 				do {
 					/* There are probably better ways to read a string from */
 					/* a file, but this does allow you to do error checking */
 					/* (which I'm not doing) on a per character basis.      */
 					++i;
 					fread( &(name[i]), sizeof( char ), 1, input);
 				} while( name[i] != '\0' );
 	
 				if ( i != 0 )
 					strncpy( pPSET[pset].name, name, sizeof( pPSET[pset].name ) - 1 );
 				else
 					strcpy( pPSET[pset].name , "(unnamed)" );
 				strlwr( pPSET[pset].name );
 
 //				indent();
 //				fprintf(stdout,"OBJECT START: %s\n",name);
 				fread( &count, sizeof(int), 1, input);
 				count = BigLong(count);
 				++iLevel;
 				if (count != 0) {
 //					indent();
 //					fprintf(stdout,"NUMBER OF TRIANGLES: %d\n",count);
 	
 					i = -1;
 					do {
 						++i;
 						fread( &(tex[i]), sizeof( char ), 1, input);
 					} while( tex[i] != '\0' );
 
 /*
 					if ( i != 0 )
 						strncpy( pPSET[pset].texname, tex, sizeof( pPSET[pset].texname ) - 1 );
 					else
 						strcpy( pPSET[pset].texname, "(unnamed)" );
 					strlwr( pPSET[pset].texname );
 */
 
 //					indent();
 //					fprintf(stdout,"  Object texture name: '%s'\n",tex);
 				}
 	
 				/* Else (count == 0) this is the start of a group, and */
 				/* no texture name is present. */
 			}
 			else if (start == FLOAT_END) {
 				/* End of an object or group. Yes, the name should be */
 				/* obvious from context, but it is in here just to be */
 				/* safe and to provide a little extra information for */
 				/* those who do not wish to write a recursive reader. */
 				/* Mea culpa. */
 				--iLevel;
 				i = -1;
 				do {
 					++i;
 					fread( &(name[i]), sizeof( char ), 1, input);
 				} while( name[i] != '\0' );
 
 				if ( i != 0 )
 					strncpy( pPSET[pset].name, name, sizeof( pPSET[pset].name ) - 1 );
 				else
 					strcpy( pPSET[pset].name , "(unnamed)" );
 
 				strlwr( pPSET[pset].name );
 	
 //				indent();
 //				fprintf(stdout,"OBJECT END: %s\n",name);
 				continue;
 			}
 		}
 
 //
 // read the triangles
 //		
 		if ( count > 0 )
 		{
 			pPSET[pset].triangles = ptri;
 			ReadPolysetGeometry( pPSET[0].triangles, input, count, ptri );
 			ptri += count;
 			pPSET[pset].numtriangles = count;
 			if ( ++pset >= POLYSET_MAXPOLYSETS )
 			{
 				Error ("Error: too many polysets; increase POLYSET_MAXPOLYSETS\n");
 			}
 		}
 	}
 
 	*numpsets = pset;
 
 	fclose (input);
 }