simgear/scene/tgdb/obj.cxx

   1 // obj.cxx -- routines to handle loading scenery and building the plib
   2 //            scene graph.
   3 //
   4 // Written by Curtis Olson, started October 1997.
   5 //
   6 // Copyright (C) 1997  Curtis L. Olson  - http://www.flightgear.org/~curt
   7 //
   8 // This program is free software; you can redistribute it and/or
   9 // modify it under the terms of the GNU General Public License as
  10 // published by the Free Software Foundation; either version 2 of the
  11 // License, or (at your option) any later version.
  12 //
  13 // This program is distributed in the hope that it will be useful, but
  14 // WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 // General Public License for more details.
  17 //
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  21 //
  22 // $Id$
  23
  24
  25 #ifdef HAVE_CONFIG_H
  26 #  include <simgear_config.h>
  27 #endif
  28
  29 #include "obj.hxx"
  30
  31 #include <simgear/compiler.h>
  32
  33 #include <osg/Fog>
  34 #include <osg/Geode>
  35 #include <osg/Geometry>
  36 #include <osg/Group>
  37 #include <osg/LOD>
  38 #include <osg/MatrixTransform>
  39 #include <osg/Point>
  40 #include <osg/StateSet>
  41 #include <osg/Switch>
  42
  43 #include <boost/foreach.hpp>
  44
  45 #include <algorithm>
  46
  47 #include <simgear/debug/logstream.hxx>
  48 #include <simgear/io/sg_binobj.hxx>
  49 #include <simgear/math/sg_geodesy.hxx>
  50 #include <simgear/math/sg_random.h>
  51 #include <simgear/math/SGMisc.hxx>
  52 #include <simgear/scene/material/Effect.hxx>
  53 #include <simgear/scene/material/EffectGeode.hxx>
  54 #include <simgear/scene/material/mat.hxx>
  55 #include <simgear/scene/material/matmodel.hxx>
  56 #include <simgear/scene/material/matlib.hxx>
  57 #include <simgear/scene/model/SGOffsetTransform.hxx>
  58 #include <simgear/scene/util/SGUpdateVisitor.hxx>
  59 #include <simgear/scene/util/SGNodeMasks.hxx>
  60 #include <simgear/scene/util/QuadTreeBuilder.hxx>
  61 #include <simgear/scene/util/SGReaderWriterOptions.hxx>
  62
  63 #include "SGTexturedTriangleBin.hxx"
  64 #include "SGLightBin.hxx"
  65 #include "SGModelBin.hxx"
  66 #include "SGBuildingBin.hxx"
  67 #include "TreeBin.hxx"
  68 #include "SGDirectionalLightBin.hxx"
  69 #include "GroundLightManager.hxx"
  70
  71
  72 #include "pt_lights.hxx"
  73
  74 using namespace simgear;
  75
  76 typedef std::map<std::string,SGTexturedTriangleBin> SGMaterialTriangleMap;
  77 typedef std::list<SGLightBin> SGLightListBin;
  78 typedef std::list<SGDirectionalLightBin> SGDirectionalLightListBin;
  79
  80 struct SGTileGeometryBin {
  81   SGMaterialTriangleMap materialTriangleMap;
  82   SGLightBin tileLights;
  83   SGLightBin randomTileLights;
  84   SGTreeBinList randomForest;
  85   SGDirectionalLightBin runwayLights;
  86   SGDirectionalLightBin taxiLights;
  87   SGDirectionalLightListBin vasiLights;
  88   SGDirectionalLightListBin rabitLights;
  89   SGLightListBin odalLights;
  90   SGDirectionalLightListBin holdshortLights;
  91   SGDirectionalLightListBin reilLights;
  92   SGMatModelBin randomModels;
  93   SGBuildingBinList randomBuildings;
  94
  95   static SGVec4f
  96   getMaterialLightColor(const SGMaterial* material)
  97   {
  98     if (!material)
  99       return SGVec4f(1, 1, 1, 0.8);
 100     return material->get_light_color();
 101   }
 102
 103   static void
 104   addPointGeometry(SGLightBin& lights,
 105                    const std::vector<SGVec3d>& vertices,
 106                    const SGVec4f& color,
 107                    const int_list& pts_v)
 108   {
 109     for (unsigned i = 0; i < pts_v.size(); ++i)
 110       lights.insert(toVec3f(vertices[pts_v[i]]), color);
 111   }
 112
 113   static void
 114   addPointGeometry(SGDirectionalLightBin& lights,
 115                    const std::vector<SGVec3d>& vertices,
 116                    const std::vector<SGVec3f>& normals,
 117                    const SGVec4f& color,
 118                    const int_list& pts_v,
 119                    const int_list& pts_n)
 120   {
 121     // If the normal indices match the vertex indices, use seperate
 122     // normal indices. Else reuse the vertex indices for the normals.
 123     if (pts_v.size() == pts_n.size()) {
 124       for (unsigned i = 0; i < pts_v.size(); ++i)
 125         lights.insert(toVec3f(vertices[pts_v[i]]), normals[pts_n[i]], color);
 126     } else {
 127       for (unsigned i = 0; i < pts_v.size(); ++i)
 128         lights.insert(toVec3f(vertices[pts_v[i]]), normals[pts_v[i]], color);
 129     }
 130   }
 131
 132   bool
 133   insertPtGeometry(const SGBinObject& obj, SGMaterialLib* matlib)
 134   {
 135     if (obj.get_pts_v().size() != obj.get_pts_n().size()) {
 136       SG_LOG(SG_TERRAIN, SG_ALERT,
 137              "Group list sizes for points do not match!");
 138       return false;
 139     }
 140
 141     for (unsigned grp = 0; grp < obj.get_pts_v().size(); ++grp) {
 142       std::string materialName = obj.get_pt_materials()[grp];
 143       SGMaterial* material = 0;
 144       if (matlib)
 145           material = matlib->find(materialName);
 146       SGVec4f color = getMaterialLightColor(material);
 147
 148       if (3 <= materialName.size() && materialName.substr(0, 3) != "RWY") {
 149         // Just plain lights. Not something for the runway.
 150         addPointGeometry(tileLights, obj.get_wgs84_nodes(), color,
 151                          obj.get_pts_v()[grp]);
 152       } else if (materialName == "RWY_BLUE_TAXIWAY_LIGHTS"
 153                  || materialName == "RWY_GREEN_TAXIWAY_LIGHTS") {
 154         addPointGeometry(taxiLights, obj.get_wgs84_nodes(), obj.get_normals(),
 155                          color, obj.get_pts_v()[grp], obj.get_pts_n()[grp]);
 156       } else if (materialName == "RWY_VASI_LIGHTS") {
 157         vasiLights.push_back(SGDirectionalLightBin());
 158         addPointGeometry(vasiLights.back(), obj.get_wgs84_nodes(),
 159                          obj.get_normals(), color, obj.get_pts_v()[grp],
 160                          obj.get_pts_n()[grp]);
 161       } else if (materialName == "RWY_SEQUENCED_LIGHTS") {
 162         rabitLights.push_back(SGDirectionalLightBin());
 163         addPointGeometry(rabitLights.back(), obj.get_wgs84_nodes(),
 164                          obj.get_normals(), color, obj.get_pts_v()[grp],
 165                          obj.get_pts_n()[grp]);
 166       } else if (materialName == "RWY_ODALS_LIGHTS") {
 167         odalLights.push_back(SGLightBin());
 168         addPointGeometry(odalLights.back(), obj.get_wgs84_nodes(),
 169                          color, obj.get_pts_v()[grp]);
 170       } else if (materialName == "RWY_YELLOW_PULSE_LIGHTS") {
 171         holdshortLights.push_back(SGDirectionalLightBin());
 172         addPointGeometry(holdshortLights.back(), obj.get_wgs84_nodes(),
 173                          obj.get_normals(), color, obj.get_pts_v()[grp],
 174                          obj.get_pts_n()[grp]);
 175       } else if (materialName == "RWY_REIL_LIGHTS") {
 176         reilLights.push_back(SGDirectionalLightBin());
 177         addPointGeometry(reilLights.back(), obj.get_wgs84_nodes(),
 178                          obj.get_normals(), color, obj.get_pts_v()[grp],
 179                          obj.get_pts_n()[grp]);
 180       } else {
 181         // what is left must be runway lights
 182         addPointGeometry(runwayLights, obj.get_wgs84_nodes(),
 183                          obj.get_normals(), color, obj.get_pts_v()[grp],
 184                          obj.get_pts_n()[grp]);
 185       }
 186     }
 187
 188     return true;
 189   }
 190
 191
 192   static SGVec2f
 193   getTexCoord(const std::vector<SGVec2f>& texCoords, const int_list& tc,
 194               const SGVec2f& tcScale, unsigned i)
 195   {
 196     if (tc.empty())
 197       return tcScale;
 198     else if (tc.size() == 1)
 199       return mult(texCoords[tc[0]], tcScale);
 200     else
 201       return mult(texCoords[tc[i]], tcScale);
 202   }
 203
 204   static void
 205   addTriangleGeometry(SGTexturedTriangleBin& triangles,
 206                       const std::vector<SGVec3d>& vertices,
 207                       const std::vector<SGVec3f>& normals,
 208                       const std::vector<SGVec2f>& texCoords,
 209                       const int_list& tris_v,
 210                       const int_list& tris_n,
 211                       const int_list& tris_tc,
 212                       const SGVec2f& tcScale)
 213   {
 214     if (tris_v.size() != tris_n.size()) {
 215       // If the normal indices do not match, they should be inmplicitly
 216       // the same than the vertex indices. So just call ourselves again
 217       // with the matching index vector.
 218       addTriangleGeometry(triangles, vertices, normals, texCoords,
 219                           tris_v, tris_v, tris_tc, tcScale);
 220       return;
 221     }
 222
 223     for (unsigned i = 2; i < tris_v.size(); i += 3) {
 224       SGVertNormTex v0;
 225       v0.vertex = toVec3f(vertices[tris_v[i-2]]);
 226       v0.normal = normals[tris_n[i-2]];
 227       v0.texCoord = getTexCoord(texCoords, tris_tc, tcScale, i-2);
 228       SGVertNormTex v1;
 229       v1.vertex = toVec3f(vertices[tris_v[i-1]]);
 230       v1.normal = normals[tris_n[i-1]];
 231       v1.texCoord = getTexCoord(texCoords, tris_tc, tcScale, i-1);
 232       SGVertNormTex v2;
 233       v2.vertex = toVec3f(vertices[tris_v[i]]);
 234       v2.normal = normals[tris_n[i]];
 235       v2.texCoord = getTexCoord(texCoords, tris_tc, tcScale, i);
 236       triangles.insert(v0, v1, v2);
 237     }
 238   }
 239
 240   static void
 241   addStripGeometry(SGTexturedTriangleBin& triangles,
 242                    const std::vector<SGVec3d>& vertices,
 243                    const std::vector<SGVec3f>& normals,
 244                    const std::vector<SGVec2f>& texCoords,
 245                    const int_list& strips_v,
 246                    const int_list& strips_n,
 247                    const int_list& strips_tc,
 248                    const SGVec2f& tcScale)
 249   {
 250     if (strips_v.size() != strips_n.size()) {
 251       // If the normal indices do not match, they should be inmplicitly
 252       // the same than the vertex indices. So just call ourselves again
 253       // with the matching index vector.
 254       addStripGeometry(triangles, vertices, normals, texCoords,
 255                        strips_v, strips_v, strips_tc, tcScale);
 256       return;
 257     }
 258
 259     for (unsigned i = 2; i < strips_v.size(); ++i) {
 260       SGVertNormTex v0;
 261       v0.vertex = toVec3f(vertices[strips_v[i-2]]);
 262       v0.normal = normals[strips_n[i-2]];
 263       v0.texCoord = getTexCoord(texCoords, strips_tc, tcScale, i-2);
 264       SGVertNormTex v1;
 265       v1.vertex = toVec3f(vertices[strips_v[i-1]]);
 266       v1.normal = normals[strips_n[i-1]];
 267       v1.texCoord = getTexCoord(texCoords, strips_tc, tcScale, i-1);
 268       SGVertNormTex v2;
 269       v2.vertex = toVec3f(vertices[strips_v[i]]);
 270       v2.normal = normals[strips_n[i]];
 271       v2.texCoord = getTexCoord(texCoords, strips_tc, tcScale, i);
 272       if (i%2)
 273         triangles.insert(v1, v0, v2);
 274       else
 275         triangles.insert(v0, v1, v2);
 276     }
 277   }
 278
 279   static void
 280   addFanGeometry(SGTexturedTriangleBin& triangles,
 281                  const std::vector<SGVec3d>& vertices,
 282                  const std::vector<SGVec3f>& normals,
 283                  const std::vector<SGVec2f>& texCoords,
 284                  const int_list& fans_v,
 285                  const int_list& fans_n,
 286                  const int_list& fans_tc,
 287                  const SGVec2f& tcScale)
 288   {
 289     if (fans_v.size() != fans_n.size()) {
 290       // If the normal indices do not match, they should be implicitly
 291       // the same than the vertex indices. So just call ourselves again
 292       // with the matching index vector.
 293       addFanGeometry(triangles, vertices, normals, texCoords,
 294                      fans_v, fans_v, fans_tc, tcScale);
 295       return;
 296     }
 297
 298     SGVertNormTex v0;
 299     v0.vertex = toVec3f(vertices[fans_v[0]]);
 300     v0.normal = normals[fans_n[0]];
 301     v0.texCoord = getTexCoord(texCoords, fans_tc, tcScale, 0);
 302     SGVertNormTex v1;
 303     v1.vertex = toVec3f(vertices[fans_v[1]]);
 304     v1.normal = normals[fans_n[1]];
 305     v1.texCoord = getTexCoord(texCoords, fans_tc, tcScale, 1);
 306     for (unsigned i = 2; i < fans_v.size(); ++i) {
 307       SGVertNormTex v2;
 308       v2.vertex = toVec3f(vertices[fans_v[i]]);
 309       v2.normal = normals[fans_n[i]];
 310       v2.texCoord = getTexCoord(texCoords, fans_tc, tcScale, i);
 311       triangles.insert(v0, v1, v2);
 312       v1 = v2;
 313     }
 314   }
 315
 316   SGVec2f getTexCoordScale(const std::string& name, SGMaterialLib* matlib)
 317   {
 318     if (!matlib)
 319       return SGVec2f(1, 1);
 320     SGMaterial* material = matlib->find(name);
 321     if (!material)
 322       return SGVec2f(1, 1);
 323
 324     return material->get_tex_coord_scale();
 325   }
 326
 327   bool
 328   insertSurfaceGeometry(const SGBinObject& obj, SGMaterialLib* matlib)
 329   {
 330     if (obj.get_tris_n().size() < obj.get_tris_v().size() ||
 331         obj.get_tris_tc().size() < obj.get_tris_v().size()) {
 332       SG_LOG(SG_TERRAIN, SG_ALERT,
 333              "Group list sizes for triangles do not match!");
 334       return false;
 335     }
 336
 337     for (unsigned grp = 0; grp < obj.get_tris_v().size(); ++grp) {
 338       std::string materialName = obj.get_tri_materials()[grp];
 339       SGVec2f tcScale = getTexCoordScale(materialName, matlib);
 340       addTriangleGeometry(materialTriangleMap[materialName],
 341                           obj.get_wgs84_nodes(), obj.get_normals(),
 342                           obj.get_texcoords(), obj.get_tris_v()[grp],
 343                           obj.get_tris_n()[grp], obj.get_tris_tc()[grp],
 344                           tcScale);
 345     }
 346
 347     if (obj.get_strips_n().size() < obj.get_strips_v().size() ||
 348         obj.get_strips_tc().size() < obj.get_strips_v().size()) {
 349       SG_LOG(SG_TERRAIN, SG_ALERT,
 350              "Group list sizes for strips do not match!");
 351       return false;
 352     }
 353     for (unsigned grp = 0; grp < obj.get_strips_v().size(); ++grp) {
 354       std::string materialName = obj.get_strip_materials()[grp];
 355       SGVec2f tcScale = getTexCoordScale(materialName, matlib);
 356       addStripGeometry(materialTriangleMap[materialName],
 357                        obj.get_wgs84_nodes(), obj.get_normals(),
 358                        obj.get_texcoords(), obj.get_strips_v()[grp],
 359                        obj.get_strips_n()[grp], obj.get_strips_tc()[grp],
 360                        tcScale);
 361     }
 362
 363     if (obj.get_fans_n().size() < obj.get_fans_v().size() ||
 364         obj.get_fans_tc().size() < obj.get_fans_v().size()) {
 365       SG_LOG(SG_TERRAIN, SG_ALERT,
 366              "Group list sizes for fans do not match!");
 367       return false;
 368     }
 369     for (unsigned grp = 0; grp < obj.get_fans_v().size(); ++grp) {
 370       std::string materialName = obj.get_fan_materials()[grp];
 371       SGVec2f tcScale = getTexCoordScale(materialName, matlib);
 372       addFanGeometry(materialTriangleMap[materialName],
 373                      obj.get_wgs84_nodes(), obj.get_normals(),
 374                      obj.get_texcoords(), obj.get_fans_v()[grp],
 375                      obj.get_fans_n()[grp], obj.get_fans_tc()[grp],
 376                      tcScale);
 377     }
 378     return true;
 379   }
 380
 381   osg::Node* getSurfaceGeometry(SGMaterialLib* matlib) const
 382   {
 383     if (materialTriangleMap.empty())
 384       return 0;
 385
 386     EffectGeode* eg = 0;
 387     osg::Group* group = (materialTriangleMap.size() > 1 ? new osg::Group : 0);
 388     //osg::Geode* geode = new osg::Geode;
 389     SGMaterialTriangleMap::const_iterator i;
 390     for (i = materialTriangleMap.begin(); i != materialTriangleMap.end(); ++i) {
 391       osg::Geometry* geometry = i->second.buildGeometry();
 392       SGMaterial *mat = 0;
 393       if (matlib)
 394         mat = matlib->find(i->first);
 395       eg = new EffectGeode;
 396       if (mat)
 397         eg->setEffect(mat->get_effect(i->second));
 398       eg->addDrawable(geometry);
 399       eg->runGenerators(geometry);  // Generate extra data needed by effect
 400       if (group)
 401         group->addChild(eg);
 402     }
 403     if (group)
 404         return group;
 405     else
 406         return eg;
 407   }
 408
 409   void computeRandomSurfaceLights(SGMaterialLib* matlib)
 410   {
 411     SGMaterialTriangleMap::iterator i;
 412
 413     // generate a repeatable random seed
 414     mt seed;
 415     mt_init(&seed, unsigned(123));
 416
 417     for (i = materialTriangleMap.begin(); i != materialTriangleMap.end(); ++i) {
 418       SGMaterial *mat = matlib->find(i->first);
 419       if (!mat)
 420         continue;
 421
 422       float coverage = mat->get_light_coverage();
 423       if (coverage <= 0)
 424         continue;
 425       if (coverage < 10000.0) {
 426         SG_LOG(SG_INPUT, SG_ALERT, "Light coverage is "
 427                << coverage << ", pushing up to 10000");
 428         coverage = 10000;
 429       }
 430
 431       std::vector<SGVec3f> randomPoints;
 432       i->second.addRandomSurfacePoints(coverage, 3, mat->get_object_mask(i->second), randomPoints);
 433       std::vector<SGVec3f>::iterator j;
 434       for (j = randomPoints.begin(); j != randomPoints.end(); ++j) {
 435         float zombie = mt_rand(&seed);
 436         // factor = sg_random() ^ 2, range = 0 .. 1 concentrated towards 0
 437         float factor = mt_rand(&seed);
 438         factor *= factor;
 439
 440         float bright = 1;
 441         SGVec4f color;
 442         if ( zombie > 0.5 ) {
 443           // 50% chance of yellowish
 444           color = SGVec4f(0.9f, 0.9f, 0.3f, bright - factor * 0.2f);
 445         } else if (zombie > 0.15f) {
 446           // 35% chance of whitish
 447           color = SGVec4f(0.9, 0.9f, 0.8f, bright - factor * 0.2f);
 448         } else if (zombie > 0.05f) {
 449           // 10% chance of orangish
 450           color = SGVec4f(0.9f, 0.6f, 0.2f, bright - factor * 0.2f);
 451         } else {
 452           // 5% chance of redish
 453           color = SGVec4f(0.9f, 0.2f, 0.2f, bright - factor * 0.2f);
 454         }
 455         randomTileLights.insert(*j, color);
 456       }
 457     }
 458   }
 459
 460   void computeRandomObjectsAndBuildings(
 461     SGMaterialLib* matlib,
 462     float building_density,
 463     bool use_random_objects,
 464     bool use_random_buildings)
 465   {
 466     SGMaterialTriangleMap::iterator i;
 467
 468     // generate a repeatable random seed
 469     mt seed;
 470     mt_init(&seed, unsigned(123));
 471
 472     for (i = materialTriangleMap.begin(); i != materialTriangleMap.end(); ++i) {
 473       SGMaterial *mat = matlib->find(i->first);
 474       SGTexturedTriangleBin triangleBin = i->second;
 475
 476       if (!mat)
 477         continue;
 478
 479       osg::Texture2D* object_mask  = mat->get_object_mask(triangleBin);
 480       int   group_count            = mat->get_object_group_count();
 481       float building_coverage      = mat->get_building_coverage();
 482       float cos_zero_density_angle = mat->get_cos_object_zero_density_slope_angle();
 483       float cos_max_density_angle  = mat->get_cos_object_max_density_slope_angle();
 484
 485       bool found = false;
 486       SGBuildingBin* bin = NULL;
 487
 488       if (building_coverage > 0) {
 489         BOOST_FOREACH(bin, randomBuildings)
 490         {
 491           if (bin->getMaterialName() == mat->get_names()[0]) {
 492               found = true;
 493               break;
 494           }
 495         }
 496
 497         if (!found) {
 498           bin = new SGBuildingBin(mat);
 499           randomBuildings.push_back(bin);
 500         }
 501       }
 502
 503       unsigned num = i->second.getNumTriangles();
 504       int random_dropped = 0;
 505       int mask_dropped = 0;
 506       int building_dropped = 0;
 507       int triangle_dropped = 0;
 508
 509       for (unsigned i = 0; i < num; ++i) {
 510         SGTexturedTriangleBin::triangle_ref triangleRef = triangleBin.getTriangleRef(i);
 511
 512         SGVec3f vorigin = triangleBin.getVertex(triangleRef[0]).vertex;
 513         SGVec3f v0 = triangleBin.getVertex(triangleRef[1]).vertex - vorigin;
 514         SGVec3f v1 = triangleBin.getVertex(triangleRef[2]).vertex - vorigin;
 515         SGVec2f torigin = triangleBin.getVertex(triangleRef[0]).texCoord;
 516         SGVec2f t0 = triangleBin.getVertex(triangleRef[1]).texCoord - torigin;
 517         SGVec2f t1 = triangleBin.getVertex(triangleRef[2]).texCoord - torigin;
 518         SGVec3f normal = cross(v0, v1);
 519
 520         // Ensure the slope isn't too steep by checking the
 521         // cos of the angle between the slope normal and the
 522         // vertical (conveniently the z-component of the normalized
 523         // normal) and values passed in.
 524         float cos = normalize(normal).z();
 525         float slope_density = 1.0;
 526         if (cos < cos_zero_density_angle) continue; // Too steep for any objects
 527         if (cos < cos_max_density_angle) {
 528           slope_density =
 529             (cos - cos_zero_density_angle) /
 530             (cos_max_density_angle - cos_zero_density_angle);
 531         }
 532
 533         // Containers to hold the random buildings and objects generated
 534         // for this triangle for collision detection purposes.
 535         std::vector< std::pair< SGVec3f, float> > triangleObjectsList;
 536         std::vector< std::pair< SGVec3f, float> > triangleBuildingList;
 537
 538         // Compute the area
 539         float area = 0.5f*length(normal);
 540         if (area <= SGLimitsf::min())
 541           continue;
 542
 543         // Generate any random objects
 544         if (use_random_objects && (group_count > 0))
 545         {
 546           for (int j = 0; j < group_count; j++)
 547           {
 548             SGMatModelGroup *object_group =  mat->get_object_group(j);
 549             int nObjects = object_group->get_object_count();
 550
 551             if (nObjects == 0) continue;
 552
 553             // For each of the random models in the group, determine an appropriate
 554             // number of random placements and insert them.
 555             for (int k = 0; k < nObjects; k++) {
 556               SGMatModel * object = object_group->get_object(k);
 557
 558               // Determine the number of objecst to place, taking into account
 559               // the slope density factor.
 560               double n = slope_density * area / object->get_coverage_m2();
 561
 562               // Use the zombie door method to determine fractional object placement.
 563               n = n + mt_rand(&seed);
 564
 565               // place an object each unit of area
 566               while ( n > 1.0 ) {
 567                 float a = mt_rand(&seed);
 568                 float b = mt_rand(&seed);
 569                 if ( a + b > 1 ) {
 570                   a = 1 - a;
 571                   b = 1 - b;
 572                 }
 573
 574                 SGVec3f randomPoint = vorigin + a*v0 + b*v1;
 575                 float rotation = static_cast<float>(mt_rand(&seed));
 576
 577                 // Check that the point is sufficiently far from
 578                 // the edge of the triangle by measuring the distance
 579                 // from the three lines that make up the triangle.
 580                 float spacing = object->get_spacing_m();
 581
 582                 SGVec3f p = randomPoint - vorigin;
 583                 float edges[] = { length(cross(p     , p - v0)) / length(v0),
 584                                   length(cross(p - v0, p - v1)) / length(v1 - v0),
 585                                   length(cross(p - v1, p     )) / length(v1)      };
 586                 float edge_dist = *std::min_element(edges, edges + 3);
 587
 588                 if (edge_dist < spacing) {
 589                   n -= 1.0;
 590                   continue;
 591                 }
 592
 593                 if (object_mask != NULL) {
 594                   SGVec2f texCoord = torigin + a*t0 + b*t1;
 595
 596                   // Check this random point against the object mask
 597                   // blue (for buildings) channel.
 598                   osg::Image* img = object_mask->getImage();
 599                   unsigned int x = (int) (img->s() * texCoord.x()) % img->s();
 600                   unsigned int y = (int) (img->t() * texCoord.y()) % img->t();
 601
 602                   if (mt_rand(&seed) > img->getColor(x, y).b()) {
 603                     // Failed object mask check
 604                     n -= 1.0;
 605                     continue;
 606                   }
 607
 608                   rotation = img->getColor(x,y).r();
 609                 }
 610
 611                 bool close = false;
 612
 613                 // Check it isn't too close to any other random objects in the triangle
 614                 std::vector<std::pair<SGVec3f, float> >::iterator l;
 615                 for (l = triangleObjectsList.begin(); l != triangleObjectsList.end(); ++l) {
 616                   float min_dist2 = (l->second + object->get_spacing_m()) *
 617                                     (l->second + object->get_spacing_m());
 618
 619                   if (distSqr(l->first, randomPoint) > min_dist2) {
 620                     close = true;
 621                     continue;
 622                   }
 623                 }
 624
 625                 if (!close) {
 626                     triangleObjectsList.push_back(std::make_pair(randomPoint, object->get_spacing_m()));
 627                     randomModels.insert(randomPoint,
 628                                         object,
 629                                         (int)object->get_randomized_range_m(&seed),
 630                                         rotation);
 631                 }
 632
 633                 n -= 1.0;
 634               }
 635             }
 636           }
 637         }
 638
 639         // Random objects now generated.  Now generate the random buildings (if any);
 640         if (use_random_buildings && (building_coverage > 0) && (building_density > 0)) {
 641
 642           // Calculate the number of buildings, taking into account building density (which is linear)
 643           // and the slope density factor.
 644           double num = building_density * building_density * slope_density * area / building_coverage;
 645
 646           // For partial units of area, use a zombie door method to
 647           // create the proper random chance of an object being created
 648           // for this triangle.
 649           num = num + mt_rand(&seed);
 650
 651           if (num < 1.0f) {
 652             continue;
 653           }
 654
 655           // Cosine of the angle between the two vectors.
 656           float cosine = (dot(v0, v1) / (length(v0) * length(v1)));
 657
 658           // Determine a grid spacing in each vector such that the correct
 659           // coverage will result.
 660           float stepv0 = (sqrtf(building_coverage) / building_density) / length(v0) / sqrtf(1 - cosine * cosine);
 661           float stepv1 = (sqrtf(building_coverage) / building_density) / length(v1);
 662
 663           stepv0 = std::min(stepv0, 1.0f);
 664           stepv1 = std::min(stepv1, 1.0f);
 665
 666           // Start at a random point. a will be immediately incremented below.
 667           float a = -mt_rand(&seed) * stepv0;
 668           float b = mt_rand(&seed) * stepv1;
 669
 670           // Place an object each unit of area
 671           while (num > 1.0) {
 672
 673             // Set the next location to place a building
 674             a += stepv0;
 675
 676             if ((a + b) > 1.0f) {
 677               // Reached the end of the scan-line on v0. Reset and increment
 678               // scan-line on v1
 679               a = mt_rand(&seed) * stepv0;
 680               b += stepv1;
 681             }
 682
 683             if (b > 1.0f) {
 684               // In a degenerate case of a single point, we might be outside the
 685               // scanline.  Note that we need to still ensure that a+b < 1.
 686               b = mt_rand(&seed) * stepv1 * (1.0f - a);
 687             }
 688
 689             if ((a + b) > 1.0f ) {
 690               // Truly degenerate case - simply choose a random point guaranteed
 691               // to fulfil the constraing of a+b < 1.
 692               a = mt_rand(&seed);
 693               b = mt_rand(&seed) * (1.0f - a);
 694             }
 695
 696             SGVec3f randomPoint = vorigin + a*v0 + b*v1;
 697             float rotation = mt_rand(&seed);
 698
 699             if (object_mask != NULL) {
 700               SGVec2f texCoord = torigin + a*t0 + b*t1;
 701               osg::Image* img = object_mask->getImage();
 702               int x = (int) (img->s() * texCoord.x()) % img->s();
 703               int y = (int) (img->t() * texCoord.y()) % img->t();
 704
 705               // In some degenerate cases x or y can be < 1, in which case the mod operand fails
 706               while (x < 0) x += img->s();
 707               while (y < 0) y += img->t();
 708
 709               if (mt_rand(&seed) < img->getColor(x, y).b()) {
 710                 // Object passes mask. Rotation is taken from the red channel
 711                 rotation = img->getColor(x,y).r();
 712               } else {
 713                 // Fails mask test - try again.
 714                 mask_dropped++;
 715                 num -= 1.0;
 716                 continue;
 717               }
 718             }
 719
 720             // Check building isn't too close to the triangle edge.
 721             float type_roll = mt_rand(&seed);
 722             SGBuildingBin::BuildingType buildingtype = bin->getBuildingType(type_roll);
 723             float radius = bin->getBuildingMaxRadius(buildingtype);
 724
 725             // Determine the actual center of the building, by shifting from the
 726             // center of the front face to the true center.
 727             osg::Matrix rotationMat = osg::Matrix::rotate(- rotation * M_PI * 2,
 728                                                  osg::Vec3f(0.0, 0.0, 1.0));
 729             SGVec3f buildingCenter = randomPoint + toSG(osg::Vec3f(-0.5 * bin->getBuildingMaxDepth(buildingtype), 0.0, 0.0) * rotationMat);
 730
 731             SGVec3f p = buildingCenter - vorigin;
 732             float edges[] = { length(cross(p     , p - v0)) / length(v0),
 733                               length(cross(p - v0, p - v1)) / length(v1 - v0),
 734                               length(cross(p - v1, p     )) / length(v1)      };
 735             float edge_dist = *std::min_element(edges, edges + 3);
 736
 737             if (edge_dist < radius) {
 738               num -= 1.0;
 739               triangle_dropped++;
 740               continue;
 741             }
 742
 743             // Check building isn't too close to random objects and other buildings.
 744             bool close = false;
 745             std::vector<std::pair<SGVec3f, float> >::iterator iter;
 746
 747             for (iter = triangleBuildingList.begin(); iter != triangleBuildingList.end(); ++iter) {
 748               float min_dist = iter->second + radius;
 749               if (distSqr(iter->first, buildingCenter) < min_dist * min_dist) {
 750                 close = true;
 751                 continue;
 752               }
 753             }
 754
 755             if (close) {
 756               num -= 1.0;
 757               building_dropped++;
 758               continue;
 759             }
 760
 761             for (iter = triangleObjectsList.begin(); iter != triangleObjectsList.end(); ++iter) {
 762               float min_dist = iter->second + radius;
 763               if (distSqr(iter->first, buildingCenter) < min_dist * min_dist) {
 764                 close = true;
 765                 continue;
 766               }
 767             }
 768
 769             if (close) {
 770               num -= 1.0;
 771               random_dropped++;
 772               continue;
 773             }
 774
 775             std::pair<SGVec3f, float> pt = std::make_pair(buildingCenter, radius);
 776             triangleBuildingList.push_back(pt);
 777             bin->insert(randomPoint, rotation, buildingtype);
 778             num -= 1.0;
 779           }
 780         }
 781
 782         triangleObjectsList.clear();
 783         triangleBuildingList.clear();
 784       }
 785
 786       SG_LOG(SG_TERRAIN, SG_DEBUG, "Random Buildings: " << bin->getNumBuildings());
 787       SG_LOG(SG_TERRAIN, SG_DEBUG, "  Dropped due to mask: " << mask_dropped);
 788       SG_LOG(SG_TERRAIN, SG_DEBUG, "  Dropped due to random object: " << random_dropped);
 789       SG_LOG(SG_TERRAIN, SG_DEBUG, "  Dropped due to other buildings: " << building_dropped);
 790     }
 791   }
 792
 793   void computeRandomForest(SGMaterialLib* matlib, float vegetation_density)
 794   {
 795     SGMaterialTriangleMap::iterator i;
 796
 797     // generate a repeatable random seed
 798     mt seed;
 799
 800     mt_init(&seed, unsigned(586));
 801
 802     for (i = materialTriangleMap.begin(); i != materialTriangleMap.end(); ++i) {
 803       SGMaterial *mat = matlib->find(i->first);
 804       if (!mat)
 805         continue;
 806
 807       float wood_coverage = mat->get_wood_coverage();
 808       if ((wood_coverage <= 0) || (vegetation_density <= 0))
 809         continue;
 810
 811       // Attributes that don't vary by tree but do vary by material
 812       bool found = false;
 813       TreeBin* bin = NULL;
 814
 815       BOOST_FOREACH(bin, randomForest)
 816       {
 817         if ((bin->texture           == mat->get_tree_texture()  ) &&
 818             (bin->texture_varieties == mat->get_tree_varieties()) &&
 819             (bin->range             == mat->get_tree_range()    ) &&
 820             (bin->width             == mat->get_tree_width()    ) &&
 821             (bin->height            == mat->get_tree_height()   )   ) {
 822             found = true;
 823             break;
 824         }
 825       }
 826
 827       if (!found) {
 828         bin = new TreeBin();
 829         bin->texture = mat->get_tree_texture();
 830           SG_LOG(SG_INPUT, SG_DEBUG, "Tree texture " << bin->texture);
 831         bin->range   = mat->get_tree_range();
 832         bin->width   = mat->get_tree_width();
 833         bin->height  = mat->get_tree_height();
 834         bin->texture_varieties = mat->get_tree_varieties();
 835         randomForest.push_back(bin);
 836       }
 837
 838       std::vector<SGVec3f> randomPoints;
 839       i->second.addRandomTreePoints(wood_coverage,
 840                                     mat->get_object_mask(i->second),
 841                                     vegetation_density,
 842                                     mat->get_cos_tree_max_density_slope_angle(),
 843                                     mat->get_cos_tree_zero_density_slope_angle(),
 844                                     randomPoints);
 845
 846       std::vector<SGVec3f>::iterator k;
 847       for (k = randomPoints.begin(); k != randomPoints.end(); ++k) {
 848         bin->insert(*k);
 849       }
 850     }
 851   }
 852
 853   bool insertBinObj(const SGBinObject& obj, SGMaterialLib* matlib)
 854   {
 855     if (!insertPtGeometry(obj, matlib))
 856       return false;
 857     if (!insertSurfaceGeometry(obj, matlib))
 858       return false;
 859     return true;
 860   }
 861 };
 862
 863 typedef std::pair<osg::Node*, int> ModelLOD;
 864 struct MakeQuadLeaf {
 865     osg::LOD* operator() () const { return new osg::LOD; }
 866 };
 867 struct AddModelLOD {
 868     void operator() (osg::LOD* leaf, ModelLOD& mlod) const
 869     {
 870         leaf->addChild(mlod.first, 0, mlod.second);
 871     }
 872 };
 873 struct GetModelLODCoord {
 874     GetModelLODCoord() {}
 875     GetModelLODCoord(const GetModelLODCoord& rhs)
 876     {}
 877     osg::Vec3 operator() (const ModelLOD& mlod) const
 878     {
 879         return mlod.first->getBound().center();
 880     }
 881 };
 882
 883 typedef QuadTreeBuilder<osg::LOD*, ModelLOD, MakeQuadLeaf, AddModelLOD,
 884                         GetModelLODCoord>  RandomObjectsQuadtree;
 885
 886 osg::Node*
 887 SGLoadBTG(const std::string& path, const simgear::SGReaderWriterOptions* options)
 888 {
 889   SGBinObject tile;
 890   if (!tile.read_bin(path))
 891     return NULL;
 892
 893   SGMaterialLib* matlib = 0;
 894   bool use_random_objects = false;
 895   bool use_random_vegetation = false;
 896   bool use_random_buildings = false;
 897   float vegetation_density = 1.0f;
 898   float building_density = 1.0f;
 899   if (options) {
 900     matlib = options->getMaterialLib();
 901     SGPropertyNode* propertyNode = options->getPropertyNode().get();
 902     if (propertyNode) {
 903         use_random_objects
 904             = propertyNode->getBoolValue("/sim/rendering/random-objects",
 905                                          use_random_objects);
 906         use_random_vegetation
 907             = propertyNode->getBoolValue("/sim/rendering/random-vegetation",
 908                                          use_random_vegetation);
 909         vegetation_density
 910             = propertyNode->getFloatValue("/sim/rendering/vegetation-density",
 911                                           vegetation_density);
 912         use_random_buildings
 913             = propertyNode->getBoolValue("/sim/rendering/random-buildings",
 914                                          use_random_buildings);
 915         building_density
 916             = propertyNode->getFloatValue("/sim/rendering/building-density",
 917                                           building_density);
 918     }
 919   }
 920
 921   SGVec3d center = tile.get_gbs_center();
 922   SGGeod geodPos = SGGeod::fromCart(center);
 923   SGQuatd hlOr = SGQuatd::fromLonLat(geodPos)*SGQuatd::fromEulerDeg(0, 0, 180);
 924
 925   // rotate the tiles so that the bounding boxes get nearly axis aligned.
 926   // this will help the collision tree's bounding boxes a bit ...
 927   std::vector<SGVec3d> nodes = tile.get_wgs84_nodes();
 928   for (unsigned i = 0; i < nodes.size(); ++i)
 929     nodes[i] = hlOr.transform(nodes[i]);
 930   tile.set_wgs84_nodes(nodes);
 931
 932   SGQuatf hlOrf(hlOr[0], hlOr[1], hlOr[2], hlOr[3]);
 933   std::vector<SGVec3f> normals = tile.get_normals();
 934   for (unsigned i = 0; i < normals.size(); ++i)
 935     normals[i] = hlOrf.transform(normals[i]);
 936   tile.set_normals(normals);
 937
 938   SGTileGeometryBin tileGeometryBin;
 939   if (!tileGeometryBin.insertBinObj(tile, matlib))
 940     return NULL;
 941
 942   SGVec3f up(0, 0, 1);
 943   GroundLightManager* lightManager = GroundLightManager::instance();
 944
 945   osg::ref_ptr<osg::Group> lightGroup = new SGOffsetTransform(0.94);
 946   osg::ref_ptr<osg::Group> randomObjects;
 947   osg::ref_ptr<osg::Group> forestNode;
 948   osg::ref_ptr<osg::Group> buildingNode;
 949   osg::Group* terrainGroup = new osg::Group;
 950
 951   osg::Node* node = tileGeometryBin.getSurfaceGeometry(matlib);
 952   if (node)
 953     terrainGroup->addChild(node);
 954
 955   if (matlib && (use_random_objects || use_random_buildings)) {
 956     tileGeometryBin.computeRandomObjectsAndBuildings(matlib,
 957                                                      building_density,
 958                                                      use_random_objects,
 959                                                      use_random_buildings);
 960   }
 961
 962   if (tileGeometryBin.randomModels.getNumModels() > 0) {
 963     // Generate a repeatable random seed
 964     mt seed;
 965     mt_init(&seed, unsigned(123));
 966
 967     std::vector<ModelLOD> models;
 968     for (unsigned int i = 0;
 969          i < tileGeometryBin.randomModels.getNumModels(); i++) {
 970       SGMatModelBin::MatModel obj
 971         = tileGeometryBin.randomModels.getMatModel(i);
 972
 973       SGPropertyNode* root = options->getPropertyNode()->getRootNode();
 974       osg::Node* node = obj.model->get_random_model(root, &seed);
 975
 976       // Create a matrix to place the object in the correct
 977       // location, and then apply the rotation matrix created
 978       // above, with an additional random (or taken from
 979       // the object mask) heading rotation if appropriate.
 980       osg::Matrix transformMat;
 981       transformMat = osg::Matrix::translate(toOsg(obj.position));
 982       if (obj.model->get_heading_type() == SGMatModel::HEADING_RANDOM) {
 983         // Rotate the object around the z axis.
 984         double hdg = mt_rand(&seed) * M_PI * 2;
 985         transformMat.preMult(osg::Matrix::rotate(hdg,
 986                                                  osg::Vec3d(0.0, 0.0, 1.0)));
 987       }
 988
 989       if (obj.model->get_heading_type() == SGMatModel::HEADING_MASK) {
 990         // Rotate the object around the z axis.
 991         double hdg =  - obj.rotation * M_PI * 2;
 992         transformMat.preMult(osg::Matrix::rotate(hdg,
 993                                                  osg::Vec3d(0.0, 0.0, 1.0)));
 994       }
 995
 996       osg::MatrixTransform* position =
 997         new osg::MatrixTransform(transformMat);
 998       position->addChild(node);
 999       models.push_back(ModelLOD(position, obj.lod));
1000     }
1001     RandomObjectsQuadtree quadtree((GetModelLODCoord()), (AddModelLOD()));
1002     quadtree.buildQuadTree(models.begin(), models.end());
1003     randomObjects = quadtree.getRoot();
1004     randomObjects->setName("Random objects");
1005   }
1006
1007   if (tileGeometryBin.randomBuildings.size() > 0) {
1008     buildingNode = createRandomBuildings(tileGeometryBin.randomBuildings, osg::Matrix::identity(),
1009                                 options);
1010     buildingNode->setName("Random buildings");
1011   }
1012
1013   if (use_random_vegetation && matlib) {
1014     // Now add some random forest.
1015     tileGeometryBin.computeRandomForest(matlib, vegetation_density);
1016
1017     if (tileGeometryBin.randomForest.size() > 0) {
1018       forestNode = createForest(tileGeometryBin.randomForest, osg::Matrix::identity(),
1019                                 options);
1020       forestNode->setName("Random trees");
1021     }
1022   }
1023
1024   // FIXME: ugly, has a side effect
1025   if (matlib)
1026     tileGeometryBin.computeRandomSurfaceLights(matlib);
1027
1028   if (tileGeometryBin.tileLights.getNumLights() > 0
1029       || tileGeometryBin.randomTileLights.getNumLights() > 0) {
1030     osg::Group* groundLights0 = new osg::Group;
1031     groundLights0->setStateSet(lightManager->getGroundLightStateSet());
1032     groundLights0->setNodeMask(GROUNDLIGHTS0_BIT);
1033     osg::Geode* geode = new osg::Geode;
1034     geode->addDrawable(SGLightFactory::getLights(tileGeometryBin.tileLights));
1035     geode->addDrawable(SGLightFactory::getLights(tileGeometryBin.randomTileLights, 4, -0.3f));
1036     groundLights0->addChild(geode);
1037     lightGroup->addChild(groundLights0);
1038   }
1039
1040   if (tileGeometryBin.randomTileLights.getNumLights() > 0) {
1041     osg::Group* groundLights1 = new osg::Group;
1042     groundLights1->setStateSet(lightManager->getGroundLightStateSet());
1043     groundLights1->setNodeMask(GROUNDLIGHTS1_BIT);
1044     osg::Group* groundLights2 = new osg::Group;
1045     groundLights2->setStateSet(lightManager->getGroundLightStateSet());
1046     groundLights2->setNodeMask(GROUNDLIGHTS2_BIT);
1047     osg::Geode* geode = new osg::Geode;
1048     geode->addDrawable(SGLightFactory::getLights(tileGeometryBin.randomTileLights, 2, -0.15f));
1049     groundLights1->addChild(geode);
1050     lightGroup->addChild(groundLights1);
1051     geode = new osg::Geode;
1052     geode->addDrawable(SGLightFactory::getLights(tileGeometryBin.randomTileLights));
1053     groundLights2->addChild(geode);
1054     lightGroup->addChild(groundLights2);
1055   }
1056
1057   if (!tileGeometryBin.vasiLights.empty()) {
1058     EffectGeode* vasiGeode = new EffectGeode;
1059     Effect* vasiEffect
1060         = getLightEffect(24, osg::Vec3(1, 0.0001, 0.000001), 1, 24, true);
1061     vasiGeode->setEffect(vasiEffect);
1062     SGVec4f red(1, 0, 0, 1);
1063     SGMaterial* mat = 0;
1064     if (matlib)
1065       mat = matlib->find("RWY_RED_LIGHTS");
1066     if (mat)
1067       red = mat->get_light_color();
1068     SGVec4f white(1, 1, 1, 1);
1069     mat = 0;
1070     if (matlib)
1071       mat = matlib->find("RWY_WHITE_LIGHTS");
1072     if (mat)
1073       white = mat->get_light_color();
1074     SGDirectionalLightListBin::const_iterator i;
1075     for (i = tileGeometryBin.vasiLights.begin();
1076          i != tileGeometryBin.vasiLights.end(); ++i) {
1077       vasiGeode->addDrawable(SGLightFactory::getVasi(up, *i, red, white));
1078     }
1079     vasiGeode->setStateSet(lightManager->getRunwayLightStateSet());
1080     lightGroup->addChild(vasiGeode);
1081   }
1082
1083   Effect* runwayEffect = 0;
1084   if (tileGeometryBin.runwayLights.getNumLights() > 0
1085       || !tileGeometryBin.rabitLights.empty()
1086       || !tileGeometryBin.reilLights.empty()
1087       || !tileGeometryBin.odalLights.empty()
1088       || tileGeometryBin.taxiLights.getNumLights() > 0)
1089       runwayEffect = getLightEffect(16, osg::Vec3(1, 0.001, 0.0002), 1, 16, true);
1090   if (tileGeometryBin.runwayLights.getNumLights() > 0
1091       || !tileGeometryBin.rabitLights.empty()
1092       || !tileGeometryBin.reilLights.empty()
1093       || !tileGeometryBin.odalLights.empty()
1094       || !tileGeometryBin.holdshortLights.empty()) {
1095     osg::Group* rwyLights = new osg::Group;
1096     rwyLights->setStateSet(lightManager->getRunwayLightStateSet());
1097     rwyLights->setNodeMask(RUNWAYLIGHTS_BIT);
1098     if (tileGeometryBin.runwayLights.getNumLights() != 0) {
1099       EffectGeode* geode = new EffectGeode;
1100       geode->setEffect(runwayEffect);
1101       geode->addDrawable(SGLightFactory::getLights(tileGeometryBin
1102                                                    .runwayLights));
1103       rwyLights->addChild(geode);
1104     }
1105     SGDirectionalLightListBin::const_iterator i;
1106     for (i = tileGeometryBin.rabitLights.begin();
1107          i != tileGeometryBin.rabitLights.end(); ++i) {
1108       rwyLights->addChild(SGLightFactory::getSequenced(*i));
1109     }
1110     for (i = tileGeometryBin.reilLights.begin();
1111          i != tileGeometryBin.reilLights.end(); ++i) {
1112       rwyLights->addChild(SGLightFactory::getSequenced(*i));
1113     }
1114     for (i = tileGeometryBin.holdshortLights.begin();
1115          i != tileGeometryBin.holdshortLights.end(); ++i) {
1116       rwyLights->addChild(SGLightFactory::getHoldShort(*i));
1117     }
1118     SGLightListBin::const_iterator j;
1119     for (j = tileGeometryBin.odalLights.begin();
1120          j != tileGeometryBin.odalLights.end(); ++j) {
1121       rwyLights->addChild(SGLightFactory::getOdal(*j));
1122     }
1123     lightGroup->addChild(rwyLights);
1124   }
1125
1126   if (tileGeometryBin.taxiLights.getNumLights() > 0) {
1127     osg::Group* taxiLights = new osg::Group;
1128     taxiLights->setStateSet(lightManager->getTaxiLightStateSet());
1129     taxiLights->setNodeMask(RUNWAYLIGHTS_BIT);
1130     EffectGeode* geode = new EffectGeode;
1131     geode->setEffect(runwayEffect);
1132     geode->addDrawable(SGLightFactory::getLights(tileGeometryBin.taxiLights));
1133     taxiLights->addChild(geode);
1134     lightGroup->addChild(taxiLights);
1135   }
1136
1137   // The toplevel transform for that tile.
1138   osg::MatrixTransform* transform = new osg::MatrixTransform;
1139   transform->setName(path);
1140   transform->setMatrix(osg::Matrix::rotate(toOsg(hlOr))*
1141                        osg::Matrix::translate(toOsg(center)));
1142   transform->addChild(terrainGroup);
1143   if (lightGroup->getNumChildren() > 0) {
1144     osg::LOD* lightLOD = new osg::LOD;
1145     lightLOD->addChild(lightGroup.get(), 0, 60000);
1146     // VASI is always on, so doesn't use light bits.
1147     lightLOD->setNodeMask(LIGHTS_BITS | MODEL_BIT | PERMANENTLIGHT_BIT);
1148     transform->addChild(lightLOD);
1149   }
1150
1151   if (randomObjects.valid() || forestNode.valid() || buildingNode.valid()) {
1152
1153     // Add a LoD node, so we don't try to display anything when the tile center
1154     // is more than 20km away.
1155     osg::LOD* objectLOD = new osg::LOD;
1156
1157     if (randomObjects.valid()) objectLOD->addChild(randomObjects.get(), 0, 20000);
1158     if (forestNode.valid())  objectLOD->addChild(forestNode.get(), 0, 20000);
1159     if (buildingNode.valid()) objectLOD->addChild(buildingNode.get(), 0, 20000);
1160
1161     unsigned nodeMask = SG_NODEMASK_CASTSHADOW_BIT | SG_NODEMASK_RECEIVESHADOW_BIT | SG_NODEMASK_TERRAIN_BIT;
1162     objectLOD->setNodeMask(nodeMask);
1163     transform->addChild(objectLOD);
1164   }
1165   transform->setNodeMask( ~simgear::MODELLIGHT_BIT );
1166
1167   return transform;
1168 }