1 /*
2 ===========================================================================
3 Copyright (C) 1997-2006 Id Software, Inc.
4
5 This file is part of Quake 2 Tools source code.
6
7 Quake 2 Tools source code is free software; you can redistribute it
8 and/or modify it under the terms of the GNU General Public License as
9 published by the Free Software Foundation; either version 2 of the License,
10 or (at your option) any later version.
11
12 Quake 2 Tools source code is distributed in the hope that it will be
13 useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with Quake 2 Tools source code; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 ===========================================================================
21 */
22
23 //
24 // trilib.c: library for loading triangles from an Alias triangle file
25 //
26
27 #include <stdio.h>
28 #include "cmdlib.h"
29 #include "mathlib.h"
30 #include "trilib.h"
31
32 // on disk representation of a face
33
34
35 #define FLOAT_START 99999.0
36 #define FLOAT_END -FLOAT_START
37 #define MAGIC 123322
38
39 //#define NOISY 1
40
41 typedef struct {
42 float v[3];
43 } vector;
44
45 typedef struct
46 {
47 vector n; /* normal */
48 vector p; /* point */
49 vector c; /* color */
50 float u; /* u */
51 float v; /* v */
52 } aliaspoint_t;
53
54 typedef struct {
55 aliaspoint_t pt[3];
56 } tf_triangle;
57
58
ByteSwapTri(tf_triangle * tri)59 void ByteSwapTri (tf_triangle *tri)
60 {
61 int i;
62
63 for (i=0 ; i<sizeof(tf_triangle)/4 ; i++)
64 {
65 ((int *)tri)[i] = BigLong (((int *)tri)[i]);
66 }
67 }
68
LoadTriangleList(char * filename,triangle_t ** pptri,int * numtriangles)69 void LoadTriangleList (char *filename, triangle_t **pptri, int *numtriangles)
70 {
71 FILE *input;
72 float start;
73 char name[256], tex[256];
74 int i, count, magic;
75 tf_triangle tri;
76 triangle_t *ptri;
77 int iLevel;
78 int exitpattern;
79 float t;
80
81 t = -FLOAT_START;
82 *((unsigned char *)&exitpattern + 0) = *((unsigned char *)&t + 3);
83 *((unsigned char *)&exitpattern + 1) = *((unsigned char *)&t + 2);
84 *((unsigned char *)&exitpattern + 2) = *((unsigned char *)&t + 1);
85 *((unsigned char *)&exitpattern + 3) = *((unsigned char *)&t + 0);
86
87 if ((input = fopen(filename, "rb")) == 0)
88 Error ("reader: could not open file '%s'", filename);
89
90 iLevel = 0;
91
92 fread(&magic, sizeof(int), 1, input);
93 if (BigLong(magic) != MAGIC)
94 Error ("%s is not a Alias object separated triangle file, magic number is wrong.", filename);
95
96 ptri = malloc (MAXTRIANGLES * sizeof(triangle_t));
97
98 *pptri = ptri;
99
100 while (feof(input) == 0) {
101 if (fread(&start, sizeof(float), 1, input) < 1)
102 break;
103 *(int *)&start = BigLong(*(int *)&start);
104 if (*(int *)&start != exitpattern)
105 {
106 if (start == FLOAT_START) {
107 /* Start of an object or group of objects. */
108 i = -1;
109 do {
110 /* There are probably better ways to read a string from */
111 /* a file, but this does allow you to do error checking */
112 /* (which I'm not doing) on a per character basis. */
113 ++i;
114 fread( &(name[i]), sizeof( char ), 1, input);
115 } while( name[i] != '\0' );
116
117 // indent();
118 // fprintf(stdout,"OBJECT START: %s\n",name);
119 fread( &count, sizeof(int), 1, input);
120 count = BigLong(count);
121 ++iLevel;
122 if (count != 0) {
123 // indent();
124 // fprintf(stdout,"NUMBER OF TRIANGLES: %d\n",count);
125
126 i = -1;
127 do {
128 ++i;
129 fread( &(tex[i]), sizeof( char ), 1, input);
130 } while( tex[i] != '\0' );
131
132 // indent();
133 // fprintf(stdout," Object texture name: '%s'\n",tex);
134 }
135
136 /* Else (count == 0) this is the start of a group, and */
137 /* no texture name is present. */
138 }
139 else if (start == FLOAT_END) {
140 /* End of an object or group. Yes, the name should be */
141 /* obvious from context, but it is in here just to be */
142 /* safe and to provide a little extra information for */
143 /* those who do not wish to write a recursive reader. */
144 /* Mia culpa. */
145 --iLevel;
146 i = -1;
147 do {
148 ++i;
149 fread( &(name[i]), sizeof( char ), 1, input);
150 } while( name[i] != '\0' );
151
152 // indent();
153 // fprintf(stdout,"OBJECT END: %s\n",name);
154 continue;
155 }
156 }
157
158 //
159 // read the triangles
160 //
161 for (i = 0; i < count; ++i) {
162 int j;
163
164 fread( &tri, sizeof(tf_triangle), 1, input );
165 ByteSwapTri (&tri);
166 for (j=0 ; j<3 ; j++)
167 {
168 int k;
169
170 for (k=0 ; k<3 ; k++)
171 {
172 ptri->verts[j][k] = tri.pt[j].p.v[k];
173 }
174 }
175
176 ptri++;
177
178 if ((ptri - *pptri) >= MAXTRIANGLES)
179 Error ("Error: too many triangles; increase MAXTRIANGLES\n");
180 }
181 }
182
183 *numtriangles = ptri - *pptri;
184
185 fclose (input);
186 }
187
188