src/Objects/obj.cxx

   1 // obj.cxx -- routines to handle "sorta" WaveFront .obj format files.
   2 //
   3 // Written by Curtis Olson, started October 1997.
   4 //
   5 // Copyright (C) 1997  Curtis L. Olson  - curt@infoplane.com
   6 //
   7 // This program is free software; you can redistribute it and/or
   8 // modify it under the terms of the GNU General Public License as
   9 // published by the Free Software Foundation; either version 2 of the
  10 // License, or (at your option) any later version.
  11 //
  12 // This program is distributed in the hope that it will be useful, but
  13 // WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 // General Public License for more details.
  16 //
  17 // You should have received a copy of the GNU General Public License
  18 // along with this program; if not, write to the Free Software
  19 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 //
  21 // $Id$
  22
  23
  24 #ifdef HAVE_CONFIG_H
  25 #  include <config.h>
  26 #endif
  27
  28 #ifdef FG_MATH_EXCEPTION_CLASH
  29 #  include <math.h>
  30 #endif
  31
  32 #ifdef HAVE_WINDOWS_H
  33 #  include <windows.h>
  34 #endif
  35
  36 #include <stdio.h>
  37 #include <string.h>
  38 #include <GL/glut.h>
  39 #include <XGL/xgl.h>
  40
  41 // #if defined ( __sun__ )
  42 // extern "C" void *memmove(void *, const void *, size_t);
  43 // extern "C" void *memset(void *, int, size_t);
  44 // #endif
  45
  46 #include <Include/compiler.h>
  47
  48 #include STL_STRING
  49 #include <map>                  // STL
  50 #include <vector>               // STL
  51 #include <ctype.h>              // isdigit()
  52
  53 #include <Debug/logstream.hxx>
  54 #include <Misc/fgstream.hxx>
  55 #include <Include/fg_constants.h>
  56 #include <Main/options.hxx>
  57 #include <Math/mat3.h>
  58 #include <Math/fg_random.h>
  59 #include <Math/point3d.hxx>
  60 #include <Math/polar3d.hxx>
  61 #include <Misc/stopwatch.hxx>
  62 #include <Scenery/tileentry.hxx>
  63
  64 #include "materialmgr.hxx"
  65 #include "obj.hxx"
  66
  67 FG_USING_STD(string);
  68 FG_USING_STD(vector);
  69
  70
  71 typedef vector < int > int_list;
  72 typedef int_list::iterator int_list_iterator;
  73 typedef int_list::const_iterator int_point_list_iterator;
  74
  75
  76 static double normals[FG_MAX_NODES][3];
  77 static double tex_coords[FG_MAX_NODES*3][3];
  78
  79
  80 // given three points defining a triangle, calculate the normal
  81 static void calc_normal(Point3D p1, Point3D p2,
  82                         Point3D p3, double normal[3])
  83 {
  84     double v1[3], v2[3];
  85     double temp;
  86
  87     v1[0] = p2[0] - p1[0]; v1[1] = p2[1] - p1[1]; v1[2] = p2[2] - p1[2];
  88     v2[0] = p3[0] - p1[0]; v2[1] = p3[1] - p1[1]; v2[2] = p3[2] - p1[2];
  89
  90     MAT3cross_product(normal, v1, v2);
  91     MAT3_NORMALIZE_VEC(normal,temp);
  92
  93     // fgPrintf( FG_TERRAIN, FG_DEBUG, "  Normal = %.2f %.2f %.2f\n",
  94     //           normal[0], normal[1], normal[2]);
  95 }
  96
  97
  98 #define FG_TEX_CONSTANT 69.0
  99
 100
 101 // Calculate texture coordinates for a given point.
 102 static Point3D calc_tex_coords(const Point3D& node, const Point3D& ref) {
 103     Point3D cp;
 104     Point3D pp;
 105     // double tmplon, tmplat;
 106
 107     // cout << "-> " << node[0] << " " << node[1] << " " << node[2] << endl;
 108     // cout << "-> " << ref.x() << " " << ref.y() << " " << ref.z() << endl;
 109
 110     cp = Point3D( node[0] + ref.x(),
 111                   node[1] + ref.y(),
 112                   node[2] + ref.z() );
 113
 114     pp = fgCartToPolar3d(cp);
 115
 116     // tmplon = pp.lon() * RAD_TO_DEG;
 117     // tmplat = pp.lat() * RAD_TO_DEG;
 118     // cout << tmplon << " " << tmplat << endl;
 119
 120     pp.setx( fmod(RAD_TO_DEG * FG_TEX_CONSTANT * pp.x(), 11.0) );
 121     pp.sety( fmod(RAD_TO_DEG * FG_TEX_CONSTANT * pp.y(), 11.0) );
 122
 123     if ( pp.x() < 0.0 ) {
 124         pp.setx( pp.x() + 11.0 );
 125     }
 126
 127     if ( pp.y() < 0.0 ) {
 128         pp.sety( pp.y() + 11.0 );
 129     }
 130
 131     // cout << pp << endl;
 132
 133     return(pp);
 134 }
 135
 136
 137 // Load a .obj file and build the GL fragment list
 138 ssgBranch *fgObjLoad( const string& path, FGTileEntry *t) {
 139     fgFRAGMENT fragment;
 140     Point3D pp;
 141     double approx_normal[3], normal[3] /*, scale = 0.0 */;
 142     // double x, y, z, xmax, xmin, ymax, ymin, zmax, zmin;
 143     // GLfloat sgenparams[] = { 1.0, 0.0, 0.0, 0.0 };
 144     GLint display_list = 0;
 145     int shading;
 146     bool in_fragment = false, in_faces = false;
 147     int vncount, vtcount;
 148     int n1 = 0, n2 = 0, n3 = 0, n4 = 0;
 149     int tex;
 150     int last1 = 0, last2 = 0, odd = 0;
 151     point_list nodes;
 152     Point3D node;
 153     Point3D center;
 154     double tex_width = 1000.0, tex_height = 1000.0;
 155     bool shared_done = false;
 156     int_list fan_vertices;
 157     int_list fan_tex_coords;
 158     int i;
 159     ssgSimpleState *state = NULL;
 160
 161     ssgBranch *tile = new ssgBranch () ;
 162     tile -> setName ( path.c_str() ) ;
 163
 164     // Attempt to open "path.gz" or "path"
 165     fg_gzifstream in( path );
 166     if ( ! in.is_open() ) {
 167         FG_LOG( FG_TERRAIN, FG_ALERT, "Cannot open file: " << path );
 168         return NULL;
 169     }
 170
 171     shading = current_options.get_shading();
 172
 173     in_fragment = false;
 174     t->ncount = 0;
 175     vncount = 0;
 176     vtcount = 0;
 177     t->bounding_radius = 0.0;
 178     center = t->center;
 179
 180     StopWatch stopwatch;
 181     stopwatch.start();
 182
 183     // ignore initial comments and blank lines. (priming the pump)
 184     // in >> skipcomment;
 185     string line;
 186
 187     while ( ! in.eof() ) {
 188         string token;
 189         char c;
 190
 191 #if defined( MACOS )
 192         in >> ::skipws;
 193 #else
 194         in >> skipws;
 195 #endif
 196
 197         if ( in.get( c ) && c == '#' ) {
 198             // process a comment line
 199
 200             // getline( in, line );
 201             // cout << "comment = " << line << endl;
 202
 203             in >> token;
 204
 205             if ( token == "gbs" ) {
 206                 // reference point (center offset)
 207                 in >> t->center >> t->bounding_radius;
 208                 center = t->center;
 209                 // cout << "center = " << center
 210                 //      << " radius = " << t->bounding_radius << endl;
 211             } else if ( token == "bs" ) {
 212                 // reference point (center offset)
 213                 in >> fragment.center;
 214                 in >> fragment.bounding_radius;
 215
 216                 // cout << "center = " << fragment.center
 217                 //      << " radius = " << fragment.bounding_radius << endl;
 218             } else if ( token == "usemtl" ) {
 219                 // material property specification
 220
 221                 // if first usemtl with shared_done = false, then set
 222                 // shared_done true and build the ssg shared lists
 223                 if ( ! shared_done ) {
 224                     shared_done = true;
 225
 226                     t->vtlist = new sgVec3 [ nodes.size() ];
 227                     t->vnlist = new sgVec3 [ vncount ];
 228                     t->tclist = new sgVec2 [ vtcount ];
 229
 230                     for ( i = 0; i < (int)nodes.size(); ++i ) {
 231                         sgSetVec3( t->vtlist[i],
 232                                    nodes[i][0], nodes[i][1], nodes[i][2] );
 233                     }
 234                     for ( i = 0; i < vncount; ++i ) {
 235                         sgSetVec3( t->vnlist[i],
 236                                    normals[i][0],
 237                                    normals[i][1],
 238                                    normals[i][2] );
 239                     }
 240                     for ( i = 0; i < vtcount; ++i ) {
 241                         sgSetVec2( t->tclist[i],
 242                                    tex_coords[i][0], tex_coords[i][1] );
 243                     }
 244                 }
 245
 246                 // series of individual triangles
 247                 if ( in_faces ) {
 248                     xglEnd();
 249                 }
 250
 251                 // this also signals the start of a new fragment
 252                 if ( in_fragment ) {
 253                     // close out the previous structure and start the next
 254                     xglEndList();
 255                     // printf("xglEnd(); xglEndList();\n");
 256
 257                     // update fragment
 258                     fragment.display_list = display_list;
 259
 260                     // push this fragment onto the tile's object list
 261                     t->fragment_list.push_back(fragment);
 262                 } else {
 263                     in_fragment = true;
 264                 }
 265
 266                 // printf("start of fragment (usemtl)\n");
 267
 268                 display_list = xglGenLists(1);
 269                 xglNewList(display_list, GL_COMPILE);
 270                 // printf("xglGenLists(); xglNewList();\n");
 271                 in_faces = false;
 272
 273                 // reset the existing face list
 274                 // printf("cleaning a fragment with %d faces\n",
 275                 //        fragment.faces.size());
 276                 fragment.init();
 277
 278                 // scan the material line
 279                 string material;
 280                 in >> material;
 281                 fragment.tile_ptr = t;
 282
 283                 // find this material in the properties list
 284                 if ( ! material_mgr.find( material, fragment.material_ptr )) {
 285                     FG_LOG( FG_TERRAIN, FG_ALERT,
 286                             "Ack! unknown usemtl name = " << material
 287                             << " in " << path );
 288                 }
 289
 290                 // set the texture width and height values for this
 291                 // material
 292                 FGMaterial m = fragment.material_ptr->get_m();
 293                 tex_width = m.get_xsize();
 294                 tex_height = m.get_ysize();
 295                 state = fragment.material_ptr->get_state();
 296                 // cout << "(w) = " << tex_width << " (h) = "
 297                 //      << tex_width << endl;
 298
 299                 // initialize the fragment transformation matrix
 300                 /*
 301                  for ( i = 0; i < 16; i++ ) {
 302                    fragment.matrix[i] = 0.0;
 303                  }
 304                  fragment.matrix[0] = fragment.matrix[5] =
 305                  fragment.matrix[10] = fragment.matrix[15] = 1.0;
 306                 */
 307             } else {
 308                 // unknown comment, just gobble the input untill the
 309                 // end of line
 310
 311                 in >> skipeol;
 312             }
 313         } else {
 314             in.putback( c );
 315
 316             in >> token;
 317
 318             // cout << "token = " << token << endl;
 319
 320             if ( token == "vn" ) {
 321                 // vertex normal
 322                 if ( vncount < FG_MAX_NODES ) {
 323                     in >> normals[vncount][0]
 324                        >> normals[vncount][1]
 325                        >> normals[vncount][2];
 326                     vncount++;
 327                 } else {
 328                     FG_LOG( FG_TERRAIN, FG_ALERT,
 329                             "Read too many vertex normals in " << path
 330                             << " ... dying :-(" );
 331                     exit(-1);
 332                 }
 333             } else if ( token == "vt" ) {
 334                 // vertex texture coordinate
 335                 if ( vtcount < FG_MAX_NODES*3 ) {
 336                     in >> tex_coords[vtcount][0]
 337                        >> tex_coords[vtcount][1];
 338                     vtcount++;
 339                 } else {
 340                     FG_LOG( FG_TERRAIN, FG_ALERT,
 341                             "Read too many vertex texture coords in " << path
 342                             << " ... dying :-("
 343                             );
 344                     exit(-1);
 345                 }
 346             } else if ( token == "v" ) {
 347                 // node (vertex)
 348                 if ( t->ncount < FG_MAX_NODES ) {
 349                     /* in >> nodes[t->ncount][0]
 350                        >> nodes[t->ncount][1]
 351                        >> nodes[t->ncount][2]; */
 352                     in >> node;
 353                     nodes.push_back(node);
 354                     t->ncount++;
 355                 } else {
 356                     FG_LOG( FG_TERRAIN, FG_ALERT,
 357                             "Read too many nodes in " << path
 358                             << " ... dying :-(");
 359                     exit(-1);
 360                 }
 361             } else if ( token == "t" ) {
 362                 // start a new triangle strip
 363
 364                 n1 = n2 = n3 = n4 = 0;
 365
 366                 // fgPrintf( FG_TERRAIN, FG_DEBUG,
 367                 //           "    new tri strip = %s", line);
 368                 in >> n1 >> n2 >> n3;
 369                 fragment.add_face(n1, n2, n3);
 370
 371                 // fgPrintf( FG_TERRAIN, FG_DEBUG, "(t) = ");
 372
 373                 xglBegin(GL_TRIANGLE_STRIP);
 374                 // printf("xglBegin(tristrip) %d %d %d\n", n1, n2, n3);
 375
 376                 odd = 1;
 377                 // scale = 1.0;
 378
 379                 if ( shading ) {
 380                     // Shading model is "GL_SMOOTH" so use precalculated
 381                     // (averaged) normals
 382                     // MAT3_SCALE_VEC(normal, normals[n1], scale);
 383                     xglNormal3dv(normal);
 384                     pp = calc_tex_coords(nodes[n1], center);
 385                     xglTexCoord2f(pp.lon(), pp.lat());
 386                     xglVertex3dv(nodes[n1].get_n());
 387
 388                     // MAT3_SCALE_VEC(normal, normals[n2], scale);
 389                     xglNormal3dv(normal);
 390                     pp = calc_tex_coords(nodes[n2], center);
 391                     xglTexCoord2f(pp.lon(), pp.lat());
 392                     xglVertex3dv(nodes[n2].get_n());
 393
 394                     // MAT3_SCALE_VEC(normal, normals[n3], scale);
 395                     xglNormal3dv(normal);
 396                     pp = calc_tex_coords(nodes[n3], center);
 397                     xglTexCoord2f(pp.lon(), pp.lat());
 398                     xglVertex3dv(nodes[n3].get_n());
 399                 } else {
 400                     // Shading model is "GL_FLAT" so calculate per face
 401                     // normals on the fly.
 402                     if ( odd ) {
 403                         calc_normal(nodes[n1], nodes[n2],
 404                                     nodes[n3], approx_normal);
 405                     } else {
 406                         calc_normal(nodes[n2], nodes[n1],
 407                                     nodes[n3], approx_normal);
 408                     }
 409                     // MAT3_SCALE_VEC(normal, approx_normal, scale);
 410                     xglNormal3dv(normal);
 411
 412                     pp = calc_tex_coords(nodes[n1], center);
 413                     xglTexCoord2f(pp.lon(), pp.lat());
 414                     xglVertex3dv(nodes[n1].get_n());
 415
 416                     pp = calc_tex_coords(nodes[n2], center);
 417                     xglTexCoord2f(pp.lon(), pp.lat());
 418                     xglVertex3dv(nodes[n2].get_n());
 419
 420                     pp = calc_tex_coords(nodes[n3], center);
 421                     xglTexCoord2f(pp.lon(), pp.lat());
 422                     xglVertex3dv(nodes[n3].get_n());
 423                 }
 424                 // printf("some normals, texcoords, and vertices\n");
 425
 426                 odd = 1 - odd;
 427                 last1 = n2;
 428                 last2 = n3;
 429
 430                 // There can be three or four values
 431                 char c;
 432                 while ( in.get(c) ) {
 433                     if ( c == '\n' ) {
 434                         break; // only the one
 435                     }
 436                     if ( isdigit(c) ){
 437                         in.putback(c);
 438                         in >> n4;
 439                         break;
 440                     }
 441                 }
 442
 443                 if ( n4 > 0 ) {
 444                     fragment.add_face(n3, n2, n4);
 445
 446                     if ( shading ) {
 447                         // Shading model is "GL_SMOOTH"
 448                         // MAT3_SCALE_VEC(normal, normals[n4], scale);
 449                     } else {
 450                         // Shading model is "GL_FLAT"
 451                         calc_normal(nodes[n3], nodes[n2], nodes[n4],
 452                                     approx_normal);
 453                         // MAT3_SCALE_VEC(normal, approx_normal, scale);
 454                     }
 455                     xglNormal3dv(normal);
 456                     pp = calc_tex_coords(nodes[n4], center);
 457                     xglTexCoord2f(pp.lon(), pp.lat());
 458                     xglVertex3dv(nodes[n4].get_n());
 459
 460                     odd = 1 - odd;
 461                     last1 = n3;
 462                     last2 = n4;
 463                     // printf("a normal, texcoord, and vertex (4th)\n");
 464                 }
 465             } else if ( token == "tf" ) {
 466                 // triangle fan
 467                 // fgPrintf( FG_TERRAIN, FG_DEBUG, "new fan");
 468
 469                 fan_vertices.clear();
 470                 fan_tex_coords.clear();
 471
 472                 xglBegin(GL_TRIANGLE_FAN);
 473
 474                 in >> n1;
 475                 fan_vertices.push_back( n1 );
 476                 xglNormal3dv(normals[n1]);
 477                 if ( in.get( c ) && c == '/' ) {
 478                     in >> tex;
 479                     fan_tex_coords.push_back( tex );
 480                     pp.setx( tex_coords[tex][0] * (1000.0 / tex_width) );
 481                     pp.sety( tex_coords[tex][1] * (1000.0 / tex_height) );
 482                 } else {
 483                     in.putback( c );
 484                     pp = calc_tex_coords(nodes[n1], center);
 485                 }
 486                 xglTexCoord2f(pp.x(), pp.y());
 487                 xglVertex3dv(nodes[n1].get_n());
 488
 489                 in >> n2;
 490                 fan_vertices.push_back( n2 );
 491                 xglNormal3dv(normals[n2]);
 492                 if ( in.get( c ) && c == '/' ) {
 493                     in >> tex;
 494                     fan_tex_coords.push_back( tex );
 495                     pp.setx( tex_coords[tex][0] * (1000.0 / tex_width) );
 496                     pp.sety( tex_coords[tex][1] * (1000.0 / tex_height) );
 497                 } else {
 498                     in.putback( c );
 499                     pp = calc_tex_coords(nodes[n2], center);
 500                 }
 501                 xglTexCoord2f(pp.x(), pp.y());
 502                 xglVertex3dv(nodes[n2].get_n());
 503
 504                 // read all subsequent numbers until next thing isn't a number
 505                 while ( true ) {
 506 #if defined( MACOS )
 507                     in >> ::skipws;
 508 #else
 509                     in >> skipws;
 510 #endif
 511
 512                     char c;
 513                     in.get(c);
 514                     in.putback(c);
 515                     if ( ! isdigit(c) || in.eof() ) {
 516                         break;
 517                     }
 518
 519                     in >> n3;
 520                     fan_vertices.push_back( n3 );
 521                     // cout << "  triangle = "
 522                     //      << n1 << "," << n2 << "," << n3
 523                     //      << endl;
 524                     xglNormal3dv(normals[n3]);
 525                     if ( in.get( c ) && c == '/' ) {
 526                         in >> tex;
 527                         fan_tex_coords.push_back( tex );
 528                         pp.setx( tex_coords[tex][0] * (1000.0 / tex_width) );
 529                         pp.sety( tex_coords[tex][1] * (1000.0 / tex_height) );
 530                     } else {
 531                         in.putback( c );
 532                         pp = calc_tex_coords(nodes[n3], center);
 533                     }
 534                     xglTexCoord2f(pp.x(), pp.y());
 535                     xglVertex3dv(nodes[n3].get_n());
 536
 537                     fragment.add_face(n1, n2, n3);
 538                     n2 = n3;
 539                 }
 540
 541                 xglEnd();
 542
 543                 // build the ssg entity
 544                 unsigned short *vindex =
 545                     new unsigned short [ fan_vertices.size() ];
 546                 unsigned short *tindex =
 547                     new unsigned short [ fan_tex_coords.size() ];
 548                 for ( i = 0; i < (int)fan_vertices.size(); ++i ) {
 549                     vindex[i] = fan_vertices[i];
 550                 }
 551                 for ( i = 0; i < (int)fan_tex_coords.size(); ++i ) {
 552                     tindex[i] = fan_tex_coords[i];
 553                 }
 554                 ssgLeaf *leaf =
 555                     new ssgVTable ( GL_TRIANGLE_FAN,
 556                                     fan_vertices.size(), vindex, t->vtlist,
 557                                     fan_vertices.size(), vindex, t->vnlist,
 558                                     fan_tex_coords.size(), tindex, t->tclist,
 559                                     0, NULL, NULL ) ;
 560                 leaf->setState( state );
 561
 562                 tile->addKid( leaf );
 563
 564             } else if ( token == "f" ) {
 565                 // unoptimized face
 566
 567                 if ( !in_faces ) {
 568                     xglBegin(GL_TRIANGLES);
 569                     // printf("xglBegin(triangles)\n");
 570                     in_faces = true;
 571                 }
 572
 573                 // fgPrintf( FG_TERRAIN, FG_DEBUG, "new triangle = %s", line);*/
 574                 in >> n1 >> n2 >> n3;
 575                 fragment.add_face(n1, n2, n3);
 576
 577                 // xglNormal3d(normals[n1][0], normals[n1][1], normals[n1][2]);
 578                 xglNormal3dv(normals[n1]);
 579                 pp = calc_tex_coords(nodes[n1], center);
 580                 xglTexCoord2f(pp.lon(), pp.lat());
 581                 xglVertex3dv(nodes[n1].get_n());
 582
 583                 xglNormal3dv(normals[n2]);
 584                 pp = calc_tex_coords(nodes[n2], center);
 585                 xglTexCoord2f(pp.lon(), pp.lat());
 586                 xglVertex3dv(nodes[n2].get_n());
 587
 588                 xglNormal3dv(normals[n3]);
 589                 pp = calc_tex_coords(nodes[n3], center);
 590                 xglTexCoord2f(pp.lon(), pp.lat());
 591                 xglVertex3dv(nodes[n3].get_n());
 592                 // printf("some normals, texcoords, and vertices (tris)\n");
 593             } else if ( token == "q" ) {
 594                 // continue a triangle strip
 595                 n1 = n2 = 0;
 596
 597                 // fgPrintf( FG_TERRAIN, FG_DEBUG, "continued tri strip = %s ",
 598                 //           line);
 599                 in >> n1;
 600
 601                 // There can be one or two values
 602                 char c;
 603                 while ( in.get(c) ) {
 604                     if ( c == '\n' ) {
 605                         break; // only the one
 606                     }
 607
 608                     if ( isdigit(c) ) {
 609                         in.putback(c);
 610                         in >> n2;
 611                         break;
 612                     }
 613                 }
 614                 // fgPrintf( FG_TERRAIN, FG_DEBUG, "read %d %d\n", n1, n2);
 615
 616                 if ( odd ) {
 617                     fragment.add_face(last1, last2, n1);
 618                 } else {
 619                     fragment.add_face(last2, last1, n1);
 620                 }
 621
 622                 if ( shading ) {
 623                     // Shading model is "GL_SMOOTH"
 624                     // MAT3_SCALE_VEC(normal, normals[n1], scale);
 625                 } else {
 626                     // Shading model is "GL_FLAT"
 627                     if ( odd ) {
 628                         calc_normal(nodes[last1], nodes[last2],
 629                                     nodes[n1], approx_normal);
 630                     } else {
 631                         calc_normal(nodes[last2], nodes[last1],
 632                                     nodes[n1], approx_normal);
 633                     }
 634                     // MAT3_SCALE_VEC(normal, approx_normal, scale);
 635                 }
 636                 xglNormal3dv(normal);
 637
 638                 pp = calc_tex_coords(nodes[n1], center);
 639                 xglTexCoord2f(pp.lon(), pp.lat());
 640                 xglVertex3dv(nodes[n1].get_n());
 641                 // printf("a normal, texcoord, and vertex (4th)\n");
 642
 643                 odd = 1 - odd;
 644                 last1 = last2;
 645                 last2 = n1;
 646
 647                 if ( n2 > 0 ) {
 648                     // fgPrintf( FG_TERRAIN, FG_DEBUG, " (cont)\n");
 649
 650                     if ( odd ) {
 651                         fragment.add_face(last1, last2, n2);
 652                     } else {
 653                         fragment.add_face(last2, last1, n2);
 654                     }
 655
 656                     if ( shading ) {
 657                         // Shading model is "GL_SMOOTH"
 658                         // MAT3_SCALE_VEC(normal, normals[n2], scale);
 659                     } else {
 660                         // Shading model is "GL_FLAT"
 661                         if ( odd ) {
 662                             calc_normal(nodes[last1], nodes[last2],
 663                                         nodes[n2], approx_normal);
 664                         } else {
 665                             calc_normal(nodes[last2], nodes[last1],
 666                                         nodes[n2], approx_normal);
 667                         }
 668                         // MAT3_SCALE_VEC(normal, approx_normal, scale);
 669                     }
 670                     xglNormal3dv(normal);
 671
 672                     pp = calc_tex_coords(nodes[n2], center);
 673                     xglTexCoord2f(pp.lon(), pp.lat());
 674                     xglVertex3dv(nodes[n2].get_n());
 675                     // printf("a normal, texcoord, and vertex (4th)\n");
 676
 677                     odd = 1 -odd;
 678                     last1 = last2;
 679                     last2 = n2;
 680                 }
 681             } else {
 682                 FG_LOG( FG_TERRAIN, FG_WARN, "Unknown token in "
 683                         << path << " = " << token );
 684             }
 685
 686             // eat white space before start of while loop so if we are
 687             // done with useful input it is noticed before hand.
 688 #if defined( MACOS )
 689             in >> ::skipws;
 690 #else
 691             in >> skipws;
 692 #endif
 693         }
 694     }
 695
 696     if ( in_fragment ) {
 697         // close out the previous structure and start the next
 698         xglEnd();
 699         xglEndList();
 700         // printf("xglEnd(); xglEndList();\n");
 701
 702         // update fragment
 703         fragment.display_list = display_list;
 704
 705         // push this fragment onto the tile's object list
 706         t->fragment_list.push_back(fragment);
 707     }
 708
 709 #if 0
 710     // Draw normal vectors (for visually verifying normals)
 711     xglBegin(GL_LINES);
 712     xglColor3f(0.0, 0.0, 0.0);
 713     for ( i = 0; i < t->ncount; i++ ) {
 714         xglVertex3d(nodes[i][0],
 715                     nodes[i][1] ,
 716                     nodes[i][2]);
 717         xglVertex3d(nodes[i][0] + 500*normals[i][0],
 718                     nodes[i][1] + 500*normals[i][1],
 719                     nodes[i][2] + 500*normals[i][2]);
 720     }
 721     xglEnd();
 722 #endif
 723
 724     t->nodes = nodes;
 725
 726     stopwatch.stop();
 727     FG_LOG( FG_TERRAIN, FG_INFO,
 728             "Loaded " << path << " in "
 729             << stopwatch.elapsedSeconds() << " seconds" );
 730
 731     return tile;
 732 }
 733
 734