src/Scenery/scenery.cxx

   1 // scenery.cxx -- data structures and routines for managing scenery.
   2 //
   3 // Written by Curtis Olson, started May 1997.
   4 //
   5 // Copyright (C) 1997  Curtis L. Olson  - http://www.flightgear.org/~curt
   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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  20 //
  21 // $Id$
  22
  23
  24 #ifdef HAVE_CONFIG_H
  25 #  include <config.h>
  26 #endif
  27
  28 #include <stdio.h>
  29 #include <string.h>
  30
  31 #include <osg/Camera>
  32 #include <osg/Transform>
  33 #include <osg/MatrixTransform>
  34 #include <osg/PositionAttitudeTransform>
  35 #include <osg/CameraView>
  36 #include <osgViewer/Viewer>
  37
  38 #include <simgear/constants.h>
  39 #include <simgear/sg_inlines.h>
  40 #include <simgear/debug/logstream.hxx>
  41 #include <simgear/scene/tgdb/userdata.hxx>
  42 #include <simgear/scene/material/matlib.hxx>
  43 #include <simgear/scene/material/mat.hxx>
  44 #include <simgear/scene/util/SGNodeMasks.hxx>
  45 #include <simgear/scene/util/OsgMath.hxx>
  46 #include <simgear/scene/util/SGSceneUserData.hxx>
  47 #include <simgear/scene/model/CheckSceneryVisitor.hxx>
  48 #include <simgear/bvh/BVHNode.hxx>
  49 #include <simgear/bvh/BVHLineSegmentVisitor.hxx>
  50
  51 #include <Viewer/renderer.hxx>
  52 #include <Main/fg_props.hxx>
  53
  54 #include "tilemgr.hxx"
  55 #include "scenery.hxx"
  56
  57 using namespace flightgear;
  58 using namespace simgear;
  59
  60 class FGGroundPickCallback : public SGPickCallback {
  61 public:
  62   virtual bool buttonPressed(int button, const Info& info)
  63   {
  64     // only on left mouse button
  65     if (button != 0)
  66       return false;
  67
  68     SGGeod geod = SGGeod::fromCart(info.wgs84);
  69     SG_LOG( SG_TERRAIN, SG_INFO, "Got ground pick at " << geod );
  70
  71     SGPropertyNode *c = fgGetNode("/sim/input/click", true);
  72     c->setDoubleValue("longitude-deg", geod.getLongitudeDeg());
  73     c->setDoubleValue("latitude-deg", geod.getLatitudeDeg());
  74     c->setDoubleValue("elevation-m", geod.getElevationM());
  75     c->setDoubleValue("elevation-ft", geod.getElevationFt());
  76     fgSetBool("/sim/signals/click", 1);
  77
  78     return true;
  79   }
  80 };
  81
  82 class FGSceneryIntersect : public osg::NodeVisitor {
  83 public:
  84     FGSceneryIntersect(const SGLineSegmentd& lineSegment,
  85                        const osg::Node* skipNode) :
  86         osg::NodeVisitor(osg::NodeVisitor::TRAVERSE_ACTIVE_CHILDREN),
  87         _lineSegment(lineSegment),
  88         _skipNode(skipNode),
  89         _material(0),
  90         _haveHit(false)
  91     { }
  92
  93     bool getHaveHit() const
  94     { return _haveHit; }
  95     const SGLineSegmentd& getLineSegment() const
  96     { return _lineSegment; }
  97     const simgear::BVHMaterial* getMaterial() const
  98     { return _material; }
  99
 100     virtual void apply(osg::Node& node)
 101     {
 102         if (&node == _skipNode)
 103             return;
 104         if (!testBoundingSphere(node.getBound()))
 105             return;
 106
 107         addBoundingVolume(node);
 108     }
 109
 110     virtual void apply(osg::Group& group)
 111     {
 112         if (&group == _skipNode)
 113             return;
 114         if (!testBoundingSphere(group.getBound()))
 115             return;
 116
 117         traverse(group);
 118         addBoundingVolume(group);
 119     }
 120
 121     virtual void apply(osg::Transform& transform)
 122     { handleTransform(transform); }
 123     virtual void apply(osg::Camera& camera)
 124     {
 125         if (camera.getRenderOrder() != osg::Camera::NESTED_RENDER)
 126             return;
 127         handleTransform(camera);
 128     }
 129     virtual void apply(osg::CameraView& transform)
 130     { handleTransform(transform); }
 131     virtual void apply(osg::MatrixTransform& transform)
 132     { handleTransform(transform); }
 133     virtual void apply(osg::PositionAttitudeTransform& transform)
 134     { handleTransform(transform); }
 135
 136 private:
 137     void handleTransform(osg::Transform& transform)
 138     {
 139         if (&transform == _skipNode)
 140             return;
 141         // Hmm, may be this needs to be refined somehow ...
 142         if (transform.getReferenceFrame() != osg::Transform::RELATIVE_RF)
 143             return;
 144
 145         if (!testBoundingSphere(transform.getBound()))
 146             return;
 147
 148         osg::Matrix inverseMatrix;
 149         if (!transform.computeWorldToLocalMatrix(inverseMatrix, this))
 150             return;
 151         osg::Matrix matrix;
 152         if (!transform.computeLocalToWorldMatrix(matrix, this))
 153             return;
 154
 155         SGLineSegmentd lineSegment = _lineSegment;
 156         bool haveHit = _haveHit;
 157         const simgear::BVHMaterial* material = _material;
 158
 159         _haveHit = false;
 160         _lineSegment = lineSegment.transform(SGMatrixd(inverseMatrix.ptr()));
 161
 162         addBoundingVolume(transform);
 163         traverse(transform);
 164
 165         if (_haveHit) {
 166             _lineSegment = _lineSegment.transform(SGMatrixd(matrix.ptr()));
 167         } else {
 168             _lineSegment = lineSegment;
 169             _material = material;
 170             _haveHit = haveHit;
 171         }
 172     }
 173
 174     simgear::BVHNode* getNodeBoundingVolume(osg::Node& node)
 175     {
 176         SGSceneUserData* userData = SGSceneUserData::getSceneUserData(&node);
 177         if (!userData)
 178             return 0;
 179         return userData->getBVHNode();
 180     }
 181     void addBoundingVolume(osg::Node& node)
 182     {
 183         simgear::BVHNode* bvNode = getNodeBoundingVolume(node);
 184         if (!bvNode)
 185             return;
 186
 187         // Find ground intersection on the bvh nodes
 188         simgear::BVHLineSegmentVisitor lineSegmentVisitor(_lineSegment,
 189                                                           0/*startTime*/);
 190         bvNode->accept(lineSegmentVisitor);
 191         if (!lineSegmentVisitor.empty()) {
 192             _lineSegment = lineSegmentVisitor.getLineSegment();
 193             _material = lineSegmentVisitor.getMaterial();
 194             _haveHit = true;
 195         }
 196     }
 197
 198     bool testBoundingSphere(const osg::BoundingSphere& bound) const
 199     {
 200         if (!bound.valid())
 201             return false;
 202
 203         SGSphered sphere(toVec3d(toSG(bound._center)), bound._radius);
 204         return intersects(_lineSegment, sphere);
 205     }
 206
 207     SGLineSegmentd _lineSegment;
 208     const osg::Node* _skipNode;
 209
 210     const simgear::BVHMaterial* _material;
 211     bool _haveHit;
 212 };
 213
 214 // Scenery Management system
 215 FGScenery::FGScenery()
 216 {
 217     SG_LOG( SG_TERRAIN, SG_INFO, "Initializing scenery subsystem" );
 218     // keep reference to pager singleton, so it cannot be destroyed while FGScenery lives
 219     _pager = FGScenery::getPagerSingleton();
 220 }
 221
 222 FGScenery::~FGScenery() {
 223 }
 224
 225
 226 // Initialize the Scenery Management system
 227 void FGScenery::init() {
 228     // Scene graph root
 229     scene_graph = new osg::Group;
 230     scene_graph->setName( "Scene" );
 231
 232     // Terrain branch
 233     terrain_branch = new osg::Group;
 234     terrain_branch->setName( "Terrain" );
 235     scene_graph->addChild( terrain_branch.get() );
 236     SGSceneUserData* userData;
 237     userData = SGSceneUserData::getOrCreateSceneUserData(terrain_branch.get());
 238     userData->setPickCallback(new FGGroundPickCallback);
 239
 240     models_branch = new osg::Group;
 241     models_branch->setName( "Models" );
 242     scene_graph->addChild( models_branch.get() );
 243
 244     aircraft_branch = new osg::Group;
 245     aircraft_branch->setName( "Aircraft" );
 246     scene_graph->addChild( aircraft_branch.get() );
 247
 248     // Initials values needed by the draw-time object loader
 249     sgUserDataInit( globals->get_props() );
 250 }
 251
 252
 253 void FGScenery::update(double dt)
 254 {
 255     SG_UNUSED(dt);
 256     // nothing here, don't call again
 257     suspend();
 258 }
 259
 260
 261 void FGScenery::bind() {
 262 }
 263
 264
 265 void FGScenery::unbind() {
 266 }
 267
 268 bool
 269 FGScenery::get_cart_elevation_m(const SGVec3d& pos, double max_altoff,
 270                                 double& alt,
 271                                 const simgear::BVHMaterial** material,
 272                                 const osg::Node* butNotFrom)
 273 {
 274   SGGeod geod = SGGeod::fromCart(pos);
 275   geod.setElevationM(geod.getElevationM() + max_altoff);
 276   return get_elevation_m(geod, alt, material, butNotFrom);
 277 }
 278
 279 bool
 280 FGScenery::get_elevation_m(const SGGeod& geod, double& alt,
 281                            const simgear::BVHMaterial** material,
 282                            const osg::Node* butNotFrom)
 283 {
 284   SGVec3d start = SGVec3d::fromGeod(geod);
 285
 286   SGGeod geodEnd = geod;
 287   geodEnd.setElevationM(SGMiscd::min(geod.getElevationM() - 10, -10000));
 288   SGVec3d end = SGVec3d::fromGeod(geodEnd);
 289
 290   FGSceneryIntersect intersectVisitor(SGLineSegmentd(start, end), butNotFrom);
 291   intersectVisitor.setTraversalMask(SG_NODEMASK_TERRAIN_BIT);
 292   get_scene_graph()->accept(intersectVisitor);
 293
 294   if (!intersectVisitor.getHaveHit())
 295       return false;
 296
 297   geodEnd = SGGeod::fromCart(intersectVisitor.getLineSegment().getEnd());
 298   alt = geodEnd.getElevationM();
 299   if (material)
 300       *material = intersectVisitor.getMaterial();
 301
 302   return true;
 303 }
 304
 305 bool
 306 FGScenery::get_cart_ground_intersection(const SGVec3d& pos, const SGVec3d& dir,
 307                                         SGVec3d& nearestHit,
 308                                         const osg::Node* butNotFrom)
 309 {
 310   // We assume that starting positions in the center of the earth are invalid
 311   if ( norm1(pos) < 1 )
 312     return false;
 313
 314   // Make really sure the direction is normalized, is really cheap compared to
 315   // computation of ground intersection.
 316   SGVec3d start = pos;
 317   SGVec3d end = start + 1e5*normalize(dir); // FIXME visibility ???
 318
 319   FGSceneryIntersect intersectVisitor(SGLineSegmentd(start, end), butNotFrom);
 320   intersectVisitor.setTraversalMask(SG_NODEMASK_TERRAIN_BIT);
 321   get_scene_graph()->accept(intersectVisitor);
 322
 323   if (!intersectVisitor.getHaveHit())
 324       return false;
 325
 326   nearestHit = intersectVisitor.getLineSegment().getEnd();
 327   return true;
 328 }
 329
 330 bool FGScenery::scenery_available(const SGGeod& position, double range_m)
 331 {
 332   if(globals->get_tile_mgr()->schedule_scenery(position, range_m, 0.0))
 333   {
 334     double elev;
 335     if (!get_elevation_m(SGGeod::fromGeodM(position, SG_MAX_ELEVATION_M), elev, 0, 0))
 336       return false;
 337     SGVec3f p = SGVec3f::fromGeod(SGGeod::fromGeodM(position, elev));
 338     osg::FrameStamp* framestamp
 339             = globals->get_renderer()->getViewer()->getFrameStamp();
 340     simgear::CheckSceneryVisitor csnv(_pager, toOsg(p), range_m, framestamp);
 341     // currently the PagedLODs will not be loaded by the DatabasePager
 342     // while the splashscreen is there, so CheckSceneryVisitor force-loads
 343     // missing objects in the main thread
 344     get_scene_graph()->accept(csnv);
 345     if(!csnv.isLoaded())
 346         return false;
 347     return true;
 348   }
 349   return false;
 350 }
 351
 352 SceneryPager* FGScenery::getPagerSingleton()
 353 {
 354     static osg::ref_ptr<SceneryPager> pager = new SceneryPager;
 355     return pager.get();
 356 }
 357