src/OBJModel.cxx

   1 /*
   2  * Copyright (C) 2006  Bjørn Lindeijer
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17  *
  18  * $Id: OBJModel.cxx,v 1.2 2006/08/12 01:26:55 b_lindeijer Exp $
  19  */
  20
  21 #include "OBJModel.h"
  22
  23 #include <GL/gl.h>
  24 #include <iostream>
  25 #include <list>
  26
  27 using namespace std;
  28
  29 static void stripNewline(char *str)
  30 {
  31   // Remove newline from the string (either \r,\n or \r\n)
  32   int len = strlen(str);
  33   if (str[len - 2] == '\r') str[len - 2] = '\0';
  34   else str[len - 1] = '\0';
  35 }
  36
  37 static string stripFilename(const string& path)
  38 {
  39   // Strip the filename portion from the given path
  40   int pos = path.rfind("/");
  41   return path.substr(0, pos + 1);
  42 }
  43
  44 static GLuint loadImage(const string& filename)
  45 {
  46   if (true) {
  47     cerr << "Error loading image " << filename << std::endl;
  48     return 0;
  49   } else {
  50     GLuint tid;
  51
  52     glGenTextures(1, &tid);
  53     glBindTexture(GL_TEXTURE_2D, tid);
  54     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  55     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  56     return tid;
  57   }
  58 }
  59
  60 OBJModel::OBJModel(const string &filename)
  61 {
  62   load(filename);
  63 }
  64
  65 OBJModel::~OBJModel()
  66 {
  67   // FIXME: Delete created materials
  68 }
  69
  70
  71 void OBJModel::render()
  72 {
  73   // TODO: Could be optimized by using vertex arrays
  74
  75   vector<Face>::iterator fi;
  76   vector<FaceVertex>::iterator vi;
  77   int v, vt, vn, vc;
  78   Material *activeMaterial = 0;
  79
  80   // Draw all faces
  81   for (fi = faces.begin(); fi != faces.end(); fi++) {
  82     // Check if we need to set new material properties
  83     if (fi->material && fi->material != activeMaterial) {
  84       glMaterialf(GL_FRONT,GL_SHININESS,fi->material->shininess);
  85       glMaterialfv(GL_FRONT,GL_AMBIENT,fi->material->ambient);
  86       glMaterialfv(GL_FRONT,GL_DIFFUSE,fi->material->diffuse);
  87       glMaterialfv(GL_FRONT,GL_SPECULAR,fi->material->specular);
  88       if (fi->material->textureId > 0) {
  89         glEnable(GL_TEXTURE_2D);
  90         glBindTexture(GL_TEXTURE_2D, fi->material->textureId);
  91       }
  92       else {
  93         glDisable(GL_TEXTURE_2D);
  94       }
  95       activeMaterial = fi->material;
  96     }
  97     glBegin(GL_POLYGON);
  98     for (vi = fi->vertices.begin(); vi != fi->vertices.end(); vi++) {
  99       v = vi->v - 1;
 100       vt = vi->vt - 1;
 101       vn = vi->vn - 1;
 102       vc = vi->vc - 1;
 103
 104       if (vt >= 0) {
 105         glTexCoord3f(
 106             vertexTextures[vt].u,
 107             vertexTextures[vt].v,
 108             vertexTextures[vt].w);
 109       }
 110       if (vc >= 0) {
 111         glColor3f(
 112             vertexColors[vc].r,
 113             vertexColors[vc].g,
 114             vertexColors[vc].b);
 115       }
 116
 117       glNormal3f(
 118           vertexNormals[vn].i,
 119           vertexNormals[vn].j,
 120           vertexNormals[vn].k);
 121
 122       glVertex4f(
 123           vertices[v].x,
 124           vertices[v].y,
 125           vertices[v].z,
 126           vertices[v].w);
 127     }
 128     glEnd();
 129   }
 130
 131   //SGNode::render();
 132 }
 133
 134
 135 void OBJModel::load(const string &filename)
 136 {
 137   vertices.clear();
 138   vertexTextures.clear();
 139   vertexNormals.clear();
 140   vertexColors.clear();
 141   faces.clear();
 142
 143   FILE* file = fopen(filename.c_str(), "r");
 144   char str[256];
 145
 146   if (!file) {
 147     cerr << "Error while opening " << filename << "!\n";
 148     return;
 149   }
 150
 151   // By default no material is used
 152   Material *activeMaterial = 0;
 153
 154   while (!feof(file)) {
 155     str[0] = '\0';
 156     fgets(str, 256, file);
 157
 158     switch (str[0]) {
 159       case 'v':
 160         switch (str[1]) {
 161           case ' ': // Plain vertex ("v x y z w")
 162             {
 163               Vertex v;
 164               sscanf(str, "v %f %f %f %f",
 165                   &(v.x), &(v.y), &(v.z), &(v.w));
 166               vertices.push_back(v);
 167               //cout << "vt " << (v.x * 0.5) << " " << (v.y * 0.5) << " " << (v.z * 0.5) << endl;
 168             }
 169             break;
 170           case 't': // Texture vertex ("vt u v w")
 171             {
 172               VertexTexture vt;
 173               sscanf(str, "vt %f %f %f", &(vt.u), &(vt.v), &(vt.w));
 174               vertexTextures.push_back(vt);
 175             }
 176             break;
 177           case 'n': // Vertex Normal ("vn i j k")
 178             {
 179               VertexNormal vn;
 180               sscanf(str, "vn %f %f %f", &(vn.i), &(vn.j), &(vn.k));
 181               vertexNormals.push_back(vn);
 182             }
 183             break;
 184           case 'c': // Vertex Color ("vc r g b a") - not standard OBJ
 185             {
 186               VertexColor vc;
 187               sscanf(str, "vc %f %f %f %f",
 188                   &(vc.r), &(vc.g), &(vc.b), &(vc.a));
 189               vertexColors.push_back(vc);
 190             }
 191             break;
 192           default: break;
 193         }
 194         break;
 195       case 'f': // Face ("f v/vt/vn v/vt/vn v/vt/vn")
 196         {
 197           char* vstr;
 198           char texlessfaces;
 199           Face f;
 200           f.material = activeMaterial;
 201
 202           vstr = strtok(&str[2], " "); // skip "f "
 203           for (; vstr; vstr = strtok(NULL," ")) {
 204             FaceVertex fv;
 205
 206             // Check if a//c or a/b/c
 207             sscanf(vstr,"%*d%*c%c", &texlessfaces);
 208             if (texlessfaces != '/') {
 209               sscanf(vstr, "%d/%d/%d", &(fv.v), &(fv.vt), &(fv.vn));
 210             } else {
 211               sscanf(vstr, "%d//%d", &(fv.v), &(fv.vn));
 212             }
 213
 214             f.vertices.push_back(fv);
 215           }
 216
 217           // Add the face to the object if there are at least 3 vertices
 218           if (f.vertices.size() >= 3) {
 219             faces.push_back(f);
 220             //cout << "f";
 221             //vector<FaceVertex>::iterator vi;
 222             //for (vi = f.vertices.begin(); vi != f.vertices.end(); vi++) {
 223             //  cout << " " << vi->v << "/" << vi->v << "/" << vi->vn;
 224             //}
 225             //cout << endl;
 226           }
 227         }
 228         break;
 229       case 'o': // Object name ("o name")
 230         {
 231           stripNewline(str);
 232           name = string(&str[2]);
 233         }
 234         break;
 235       case 'u': // ("usemtl name")
 236         if (strncmp(str, "usemtl ", 7) == 0) {
 237           stripNewline(str);
 238           string matName = string(&str[7]);
 239           if (materials.count(matName) > 0) {
 240             activeMaterial = materials[matName];
 241           }
 242         }
 243         break;
 244       case 'm': // ("mtllib file1 file2 ...")
 245         if (strncmp(str, "mtllib ", 7) == 0) {
 246           // Read material libraries
 247           string path = stripFilename(filename);
 248           char* vstr;
 249
 250           vstr = strtok(&str[7], " \r\n"); // skip "mtllib "
 251           for (; vstr; vstr = strtok(NULL," \r\n")) {
 252             loadMTL(path + string(vstr));
 253           }
 254         }
 255         break;
 256       case 's': // ("shadow_obj file")
 257         if (strncmp(str, "shadow_obj ", 11) == 0) {
 258           stripNewline(str);
 259           shadowObj = string(&str[11]);
 260         }
 261         break;
 262       default:
 263         // Nothing recognized, ignore.
 264         break;
 265     }
 266   }
 267
 268   cout << "Loaded model " << name << " (" << faces.size() << " faces)\n";
 269 }
 270
 271
 272 void OBJModel::loadMTL(const string &filename)
 273 {
 274   FILE* file = fopen(filename.c_str(), "r");
 275   if (!file) {
 276     cerr << "Error while opening " << filename << "!\n";
 277     return;
 278   }
 279
 280   char str[256];
 281   Material* mat = 0;
 282
 283   while (!feof(file)) {
 284     str[0] = '\0';
 285     fgets(str, 256, file);
 286
 287     switch (str[0]) {
 288       case 'n': // ("newmtl name")
 289         if (strncmp(str, "newmtl ", 7) == 0) {
 290           // TODO: Check if same name already exists
 291           stripNewline(str);
 292           string matName = string(&str[7]);
 293           if (materials.count(matName) == 0) {
 294             mat = new Material();
 295             mat->name = matName;
 296             materials[matName] = mat;
 297           } else {
 298             mat = materials[matName];
 299           }
 300         }
 301     }
 302
 303     if (!mat) continue;
 304
 305     switch (str[0]) {
 306       case 'K':
 307         switch (str[1]) {
 308           case 'a': // ("Ka r g b")
 309             // Ambient
 310             sscanf(str, "Ka %f %f %f",
 311                 &mat->ambient[0], &mat->ambient[1], &mat->ambient[2]);
 312             break;
 313           case 'd': // ("Kd r g b")
 314             // Diffuse
 315             sscanf(str, "Kd %f %f %f",
 316                 &mat->diffuse[0], &mat->diffuse[1], &mat->diffuse[2]);
 317             break;
 318           case 's': // ("Ks r g b")
 319             // Specular
 320             sscanf(str, "Ks %f %f %f",
 321                 &mat->specular[0],&mat->specular[1],&mat->specular[2]);
 322             break;
 323           default: break;
 324         }
 325       case 'i': // ("illum i")
 326         // Illumination model (0, 1 or 2)
 327         if (strncmp(str, "illum ", 6)) {
 328           sscanf(str, "illum %d", &mat->illuminationModel);
 329         }
 330         else if (strncmp(str, "d ", 2)) {
 331           sscanf(str, "d %d", &mat->illuminationModel);
 332         }
 333         break;
 334       case 'T':
 335         if (str[1] == 'r') {
 336           // ("Tr transparency")
 337           sscanf(str, "Tr %f", &mat->transparency);
 338         }
 339         mat->ambient[3] = mat->transparency;
 340         mat->specular[3] = mat->transparency;
 341         mat->diffuse[3] = mat->transparency;
 342         break;
 343       case 'd': // ("d transparency")
 344         sscanf(str, "d %f", &mat->transparency);
 345         mat->ambient[3] = mat->transparency;
 346         mat->specular[3] = mat->transparency;
 347         mat->diffuse[3] = mat->transparency;
 348         break;
 349       case 'N':
 350         if (str[1] == 's') {
 351           // ("Ns shininess")
 352           sscanf(str, "Ns %f", &mat->shininess);
 353         }
 354         break;
 355       case 'm':
 356         if (strncmp(str, "map_K", 5) == 0) {
 357           switch (str[5]) {
 358             case 'd': // ("map_Kd filename") - Diffuse map
 359               {
 360                 stripNewline(&str[7]);
 361                 string imageFile =
 362                   stripFilename(filename) + string(&str[7]);
 363                 mat->textureId = loadImage(imageFile);
 364                 break;
 365               }
 366             case 'a': // ("map_Ka filename") - Ambient map
 367               break;
 368             case 's': // ("map_Ks filename") - Specular map
 369               break;
 370           }
 371         }
 372         else if (strncmp(str, "map_Bump ", 9) == 0) {
 373           // ("map_Bump filename") - Bump map
 374         }
 375         else if (strncmp(str, "map_d ", 6) == 0) {
 376           // ("map_d filename") - Opacity map
 377         }
 378         break;
 379       default:
 380         // Nothing recognized, ignore.
 381         break;
 382     }
 383   }
 384 }