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