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 #include <simgear/structure/commands.hxx>
  51
  52 #include <Viewer/renderer.hxx>
  53 #include <Main/fg_props.hxx>
  54 #include <GUI/MouseCursor.hxx>
  55
  56 #include "tilemgr.hxx"
  57 #include "scenery.hxx"
  58
  59 using namespace flightgear;
  60 using namespace simgear;
  61
  62 class FGGroundPickCallback : public SGPickCallback {
  63 public:
  64   FGGroundPickCallback() : SGPickCallback(PriorityScenery)
  65   { }
  66
  67   virtual bool buttonPressed( int button,
  68                               const osgGA::GUIEventAdapter&,
  69                               const Info& info )
  70   {
  71     // only on left mouse button
  72     if (button != 0)
  73       return false;
  74
  75     SGGeod geod = SGGeod::fromCart(info.wgs84);
  76     SG_LOG( SG_TERRAIN, SG_INFO, "Got ground pick at " << geod );
  77
  78     SGPropertyNode *c = fgGetNode("/sim/input/click", true);
  79     c->setDoubleValue("longitude-deg", geod.getLongitudeDeg());
  80     c->setDoubleValue("latitude-deg", geod.getLatitudeDeg());
  81     c->setDoubleValue("elevation-m", geod.getElevationM());
  82     c->setDoubleValue("elevation-ft", geod.getElevationFt());
  83     fgSetBool("/sim/signals/click", 1);
  84
  85     return true;
  86   }
  87 };
  88
  89 class FGSceneryIntersect : public osg::NodeVisitor {
  90 public:
  91     FGSceneryIntersect(const SGLineSegmentd& lineSegment,
  92                        const osg::Node* skipNode) :
  93         osg::NodeVisitor(osg::NodeVisitor::TRAVERSE_ACTIVE_CHILDREN),
  94         _lineSegment(lineSegment),
  95         _skipNode(skipNode),
  96         _material(0),
  97         _haveHit(false)
  98     { }
  99
 100     bool getHaveHit() const
 101     { return _haveHit; }
 102     const SGLineSegmentd& getLineSegment() const
 103     { return _lineSegment; }
 104     const simgear::BVHMaterial* getMaterial() const
 105     { return _material; }
 106
 107     virtual void apply(osg::Node& node)
 108     {
 109         if (&node == _skipNode)
 110             return;
 111         if (!testBoundingSphere(node.getBound()))
 112             return;
 113
 114         addBoundingVolume(node);
 115     }
 116
 117     virtual void apply(osg::Group& group)
 118     {
 119         if (&group == _skipNode)
 120             return;
 121         if (!testBoundingSphere(group.getBound()))
 122             return;
 123
 124         traverse(group);
 125         addBoundingVolume(group);
 126     }
 127
 128     virtual void apply(osg::Transform& transform)
 129     { handleTransform(transform); }
 130     virtual void apply(osg::Camera& camera)
 131     {
 132         if (camera.getRenderOrder() != osg::Camera::NESTED_RENDER)
 133             return;
 134         handleTransform(camera);
 135     }
 136     virtual void apply(osg::CameraView& transform)
 137     { handleTransform(transform); }
 138     virtual void apply(osg::MatrixTransform& transform)
 139     { handleTransform(transform); }
 140     virtual void apply(osg::PositionAttitudeTransform& transform)
 141     { handleTransform(transform); }
 142
 143 private:
 144     void handleTransform(osg::Transform& transform)
 145     {
 146         if (&transform == _skipNode)
 147             return;
 148         // Hmm, may be this needs to be refined somehow ...
 149         if (transform.getReferenceFrame() != osg::Transform::RELATIVE_RF)
 150             return;
 151
 152         if (!testBoundingSphere(transform.getBound()))
 153             return;
 154
 155         osg::Matrix inverseMatrix;
 156         if (!transform.computeWorldToLocalMatrix(inverseMatrix, this))
 157             return;
 158         osg::Matrix matrix;
 159         if (!transform.computeLocalToWorldMatrix(matrix, this))
 160             return;
 161
 162         SGLineSegmentd lineSegment = _lineSegment;
 163         bool haveHit = _haveHit;
 164         const simgear::BVHMaterial* material = _material;
 165
 166         _haveHit = false;
 167         _lineSegment = lineSegment.transform(SGMatrixd(inverseMatrix.ptr()));
 168
 169         addBoundingVolume(transform);
 170         traverse(transform);
 171
 172         if (_haveHit) {
 173             _lineSegment = _lineSegment.transform(SGMatrixd(matrix.ptr()));
 174         } else {
 175             _lineSegment = lineSegment;
 176             _material = material;
 177             _haveHit = haveHit;
 178         }
 179     }
 180
 181     simgear::BVHNode* getNodeBoundingVolume(osg::Node& node)
 182     {
 183         SGSceneUserData* userData = SGSceneUserData::getSceneUserData(&node);
 184         if (!userData)
 185             return 0;
 186         return userData->getBVHNode();
 187     }
 188     void addBoundingVolume(osg::Node& node)
 189     {
 190         simgear::BVHNode* bvNode = getNodeBoundingVolume(node);
 191         if (!bvNode)
 192             return;
 193
 194         // Find ground intersection on the bvh nodes
 195         simgear::BVHLineSegmentVisitor lineSegmentVisitor(_lineSegment,
 196                                                           0/*startTime*/);
 197         bvNode->accept(lineSegmentVisitor);
 198         if (!lineSegmentVisitor.empty()) {
 199             _lineSegment = lineSegmentVisitor.getLineSegment();
 200             _material = lineSegmentVisitor.getMaterial();
 201             _haveHit = true;
 202         }
 203     }
 204
 205     bool testBoundingSphere(const osg::BoundingSphere& bound) const
 206     {
 207         if (!bound.valid())
 208             return false;
 209
 210         SGSphered sphere(toVec3d(toSG(bound._center)), bound._radius);
 211         return intersects(_lineSegment, sphere);
 212     }
 213
 214     SGLineSegmentd _lineSegment;
 215     const osg::Node* _skipNode;
 216
 217     const simgear::BVHMaterial* _material;
 218     bool _haveHit;
 219 };
 220
 221 // Scenery Management system
 222 FGScenery::FGScenery()
 223 {
 224     SG_LOG( SG_TERRAIN, SG_INFO, "Initializing scenery subsystem" );
 225     // keep reference to pager singleton, so it cannot be destroyed while FGScenery lives
 226     _pager = FGScenery::getPagerSingleton();
 227 }
 228
 229 FGScenery::~FGScenery() {
 230 }
 231
 232
 233 // Initialize the Scenery Management system
 234 void FGScenery::init() {
 235     // Scene graph root
 236     scene_graph = new osg::Group;
 237     scene_graph->setName( "FGScenery" );
 238
 239     // Terrain branch
 240     terrain_branch = new osg::Group;
 241     terrain_branch->setName( "Terrain" );
 242     scene_graph->addChild( terrain_branch.get() );
 243     SGSceneUserData* userData;
 244     userData = SGSceneUserData::getOrCreateSceneUserData(terrain_branch.get());
 245     userData->setPickCallback(new FGGroundPickCallback);
 246
 247     models_branch = new osg::Group;
 248     models_branch->setName( "Models" );
 249     scene_graph->addChild( models_branch.get() );
 250
 251     aircraft_branch = new osg::Group;
 252     aircraft_branch->setName( "Aircraft" );
 253     scene_graph->addChild( aircraft_branch.get() );
 254
 255     // Initials values needed by the draw-time object loader
 256     sgUserDataInit( globals->get_props() );
 257 }
 258
 259
 260 void FGScenery::update(double dt)
 261 {
 262     SG_UNUSED(dt);
 263     // nothing here, don't call again
 264     suspend();
 265 }
 266
 267
 268 void FGScenery::bind() {
 269 }
 270
 271
 272 void FGScenery::unbind() {
 273 }
 274
 275 bool
 276 FGScenery::get_cart_elevation_m(const SGVec3d& pos, double max_altoff,
 277                                 double& alt,
 278                                 const simgear::BVHMaterial** material,
 279                                 const osg::Node* butNotFrom)
 280 {
 281   SGGeod geod = SGGeod::fromCart(pos);
 282   geod.setElevationM(geod.getElevationM() + max_altoff);
 283   return get_elevation_m(geod, alt, material, butNotFrom);
 284 }
 285
 286 bool
 287 FGScenery::get_elevation_m(const SGGeod& geod, double& alt,
 288                            const simgear::BVHMaterial** material,
 289                            const osg::Node* butNotFrom)
 290 {
 291   SGVec3d start = SGVec3d::fromGeod(geod);
 292
 293   SGGeod geodEnd = geod;
 294   geodEnd.setElevationM(SGMiscd::min(geod.getElevationM() - 10, -10000));
 295   SGVec3d end = SGVec3d::fromGeod(geodEnd);
 296
 297   FGSceneryIntersect intersectVisitor(SGLineSegmentd(start, end), butNotFrom);
 298   intersectVisitor.setTraversalMask(SG_NODEMASK_TERRAIN_BIT);
 299   get_scene_graph()->accept(intersectVisitor);
 300
 301   if (!intersectVisitor.getHaveHit())
 302       return false;
 303
 304   geodEnd = SGGeod::fromCart(intersectVisitor.getLineSegment().getEnd());
 305   alt = geodEnd.getElevationM();
 306   if (material)
 307       *material = intersectVisitor.getMaterial();
 308
 309   return true;
 310 }
 311
 312 bool
 313 FGScenery::get_cart_ground_intersection(const SGVec3d& pos, const SGVec3d& dir,
 314                                         SGVec3d& nearestHit,
 315                                         const osg::Node* butNotFrom)
 316 {
 317   // We assume that starting positions in the center of the earth are invalid
 318   if ( norm1(pos) < 1 )
 319     return false;
 320
 321   // Make really sure the direction is normalized, is really cheap compared to
 322   // computation of ground intersection.
 323   SGVec3d start = pos;
 324   SGVec3d end = start + 1e5*normalize(dir); // FIXME visibility ???
 325
 326   FGSceneryIntersect intersectVisitor(SGLineSegmentd(start, end), butNotFrom);
 327   intersectVisitor.setTraversalMask(SG_NODEMASK_TERRAIN_BIT);
 328   get_scene_graph()->accept(intersectVisitor);
 329
 330   if (!intersectVisitor.getHaveHit())
 331       return false;
 332
 333   nearestHit = intersectVisitor.getLineSegment().getEnd();
 334   return true;
 335 }
 336
 337 bool FGScenery::scenery_available(const SGGeod& position, double range_m)
 338 {
 339   if(globals->get_tile_mgr()->schedule_scenery(position, range_m, 0.0))
 340   {
 341     double elev;
 342     if (!get_elevation_m(SGGeod::fromGeodM(position, SG_MAX_ELEVATION_M), elev, 0, 0))
 343       return false;
 344     SGVec3f p = SGVec3f::fromGeod(SGGeod::fromGeodM(position, elev));
 345     osg::FrameStamp* framestamp
 346             = globals->get_renderer()->getViewer()->getFrameStamp();
 347     simgear::CheckSceneryVisitor csnv(_pager, toOsg(p), range_m, framestamp);
 348     // currently the PagedLODs will not be loaded by the DatabasePager
 349     // while the splashscreen is there, so CheckSceneryVisitor force-loads
 350     // missing objects in the main thread
 351     get_scene_graph()->accept(csnv);
 352     if(!csnv.isLoaded())
 353         return false;
 354     return true;
 355   }
 356   return false;
 357 }
 358
 359 SceneryPager* FGScenery::getPagerSingleton()
 360 {
 361     static osg::ref_ptr<SceneryPager> pager = new SceneryPager;
 362     return pager.get();
 363 }
 364