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