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