src/Main/CameraGroup.cxx

   1 // Copyright (C) 2008  Tim Moore
   2 //
   3 // This program is free software; you can redistribute it and/or
   4 // modify it under the terms of the GNU General Public License as
   5 // published by the Free Software Foundation; either version 2 of the
   6 // License, or (at your option) any later version.
   7 //
   8 // This program is distributed in the hope that it will be useful, but
   9 // WITHOUT ANY WARRANTY; without even the implied warranty of
  10 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11 // General Public License for more details.
  12 //
  13 // You should have received a copy of the GNU General Public License
  14 // along with this program; if not, write to the Free Software
  15 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  16
  17 #include "CameraGroup.hxx"
  18
  19 #include "globals.hxx"
  20 #include "renderer.hxx"
  21 #include "FGEventHandler.hxx"
  22 #include "WindowBuilder.hxx"
  23 #include "WindowSystemAdapter.hxx"
  24 #include <simgear/props/props.hxx>
  25 #include <simgear/structure/OSGUtils.hxx>
  26 #include <simgear/scene/util/RenderConstants.hxx>
  27
  28 #include <algorithm>
  29 #include <cstring>
  30 #include <string>
  31
  32 #include <osg/Camera>
  33 #include <osg/GraphicsContext>
  34 #include <osg/Math>
  35 #include <osg/Matrix>
  36 #include <osg/Quat>
  37 #include <osg/Vec3d>
  38 #include <osg/Viewport>
  39
  40 #include <osgUtil/IntersectionVisitor>
  41
  42 #include <osgViewer/GraphicsWindow>
  43
  44 namespace flightgear
  45 {
  46 using namespace osg;
  47
  48 using std::strcmp;
  49 using std::string;
  50
  51 ref_ptr<CameraGroup> CameraGroup::_defaultGroup;
  52
  53 CameraGroup::CameraGroup(osgViewer::Viewer* viewer) :
  54     _viewer(viewer)
  55 {
  56 }
  57
  58 }
  59
  60 namespace
  61 {
  62 using namespace osg;
  63
  64 // Given a projection matrix, return a new one with the same frustum
  65 // sides and new near / far values.
  66
  67 void makeNewProjMat(Matrixd& oldProj, double znear,
  68                                        double zfar, Matrixd& projection)
  69 {
  70     projection = oldProj;
  71     // Slightly inflate the near & far planes to avoid objects at the
  72     // extremes being clipped out.
  73     znear *= 0.999;
  74     zfar *= 1.001;
  75
  76     // Clamp the projection matrix z values to the range (near, far)
  77     double epsilon = 1.0e-6;
  78     if (fabs(projection(0,3)) < epsilon &&
  79         fabs(projection(1,3)) < epsilon &&
  80         fabs(projection(2,3)) < epsilon) {
  81         // Projection is Orthographic
  82         epsilon = -1.0/(zfar - znear); // Used as a temp variable
  83         projection(2,2) = 2.0*epsilon;
  84         projection(3,2) = (zfar + znear)*epsilon;
  85     } else {
  86         // Projection is Perspective
  87         double trans_near = (-znear*projection(2,2) + projection(3,2)) /
  88             (-znear*projection(2,3) + projection(3,3));
  89         double trans_far = (-zfar*projection(2,2) + projection(3,2)) /
  90             (-zfar*projection(2,3) + projection(3,3));
  91         double ratio = fabs(2.0/(trans_near - trans_far));
  92         double center = -0.5*(trans_near + trans_far);
  93
  94         projection.postMult(osg::Matrixd(1.0, 0.0, 0.0, 0.0,
  95                                          0.0, 1.0, 0.0, 0.0,
  96                                          0.0, 0.0, ratio, 0.0,
  97                                          0.0, 0.0, center*ratio, 1.0));
  98     }
  99 }
 100
 101 void installCullVisitor(Camera* camera)
 102 {
 103 #if 0 // Not yet
 104     osgViewer::Renderer* renderer
 105         = static_cast<osgViewer::Renderer*>(camera->getRenderer());
 106     for (int i = 0; i < 2; ++i) {
 107         osgUtil::SceneView* sceneView = renderer->getSceneView(i);
 108         sceneView->setCullVisitor(new simgear::EffectCullVisitor);
 109     }
 110 #endif
 111 }
 112 }
 113
 114 namespace flightgear
 115 {
 116 void updateCameras(const CameraInfo* info)
 117 {
 118     if (info->camera.valid())
 119         info->camera->getViewport()->setViewport(info->x, info->y,
 120                                                  info->width, info->height);
 121     if (info->farCamera.valid())
 122         info->farCamera->getViewport()->setViewport(info->x, info->y,
 123                                                     info->width, info->height);
 124 }
 125
 126 CameraInfo* CameraGroup::addCamera(unsigned flags, Camera* camera,
 127                                    const Matrix& view,
 128                                    const Matrix& projection,
 129                                    bool useMasterSceneData)
 130 {
 131     CameraInfo* info = new CameraInfo(flags);
 132     // The camera group will always update the camera
 133     camera->setReferenceFrame(Transform::ABSOLUTE_RF);
 134
 135     Camera* farCamera = 0;
 136     if ((flags & (GUI | ORTHO)) == 0) {
 137         farCamera = new Camera;
 138         farCamera->setAllowEventFocus(camera->getAllowEventFocus());
 139         farCamera->setGraphicsContext(camera->getGraphicsContext());
 140         farCamera->setCullingMode(camera->getCullingMode());
 141         farCamera->setInheritanceMask(camera->getInheritanceMask());
 142         // Each camera's viewport is written when the window is
 143         // resized; if the the viewport isn't copied here, it gets updated
 144         // twice and ends up with the wrong value.
 145         farCamera->setViewport(simgear::clone(camera->getViewport()));
 146         _viewer->addSlave(farCamera, view, projection, useMasterSceneData);
 147         installCullVisitor(farCamera);
 148         info->farCamera = farCamera;
 149         info->farSlaveIndex = _viewer->getNumSlaves() - 1;
 150         farCamera->setRenderOrder(Camera::POST_RENDER, info->farSlaveIndex);
 151         camera->setCullMask(camera->getCullMask() & ~simgear::BACKGROUND_BIT);
 152         camera->setClearMask(GL_DEPTH_BUFFER_BIT);
 153     }
 154     _viewer->addSlave(camera, view, projection, useMasterSceneData);
 155     installCullVisitor(camera);
 156     info->camera = camera;
 157     info->slaveIndex = _viewer->getNumSlaves() - 1;
 158     camera->setRenderOrder(Camera::POST_RENDER, info->slaveIndex);
 159     _cameras.push_back(info);
 160     return info;
 161 }
 162
 163 void CameraGroup::update(const osg::Vec3d& position,
 164                          const osg::Quat& orientation)
 165 {
 166     const Matrix masterView(osg::Matrix::translate(-position)
 167                             * osg::Matrix::rotate(orientation.inverse()));
 168     _viewer->getCamera()->setViewMatrix(masterView);
 169     const Matrix& masterProj = _viewer->getCamera()->getProjectionMatrix();
 170     for (CameraList::iterator i = _cameras.begin(); i != _cameras.end(); ++i) {
 171         const CameraInfo* info = i->get();
 172         const View::Slave& slave = _viewer->getSlave(info->slaveIndex);
 173         // refreshes camera viewports (for now)
 174         updateCameras(info);
 175         Camera* camera = info->camera.get();
 176         Matrix viewMatrix;
 177         if ((info->flags & VIEW_ABSOLUTE) != 0)
 178             viewMatrix = slave._viewOffset;
 179         else
 180             viewMatrix = masterView * slave._viewOffset;
 181         camera->setViewMatrix(viewMatrix);
 182         Matrix projectionMatrix;
 183         if ((info->flags & PROJECTION_ABSOLUTE) != 0)
 184             projectionMatrix = slave._projectionOffset;
 185         else
 186             projectionMatrix = masterProj * slave._projectionOffset;
 187
 188         if (!info->farCamera.valid()) {
 189             camera->setProjectionMatrix(projectionMatrix);
 190         } else {
 191             Camera* farCamera = info->farCamera.get();
 192             farCamera->setViewMatrix(viewMatrix);
 193             double left, right, bottom, top, parentNear, parentFar;
 194             projectionMatrix.getFrustum(left, right, bottom, top,
 195                                         parentNear, parentFar);
 196             if (parentFar < _nearField || _nearField == 0.0f) {
 197                 camera->setProjectionMatrix(projectionMatrix);
 198                 camera->setCullMask(camera->getCullMask()
 199                                     | simgear::BACKGROUND_BIT);
 200                 camera->setClearMask(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 201                 farCamera->setNodeMask(0);
 202             } else {
 203                 Matrix nearProj, farProj;
 204                 makeNewProjMat(projectionMatrix, parentNear, _nearField,
 205                                nearProj);
 206                 makeNewProjMat(projectionMatrix, _nearField, parentFar,
 207                                farProj);
 208                 camera->setProjectionMatrix(nearProj);
 209                 camera->setCullMask(camera->getCullMask()
 210                                     & ~simgear::BACKGROUND_BIT);
 211                 camera->setClearMask(GL_DEPTH_BUFFER_BIT);
 212                 farCamera->setProjectionMatrix(farProj);
 213                 farCamera->setNodeMask(camera->getNodeMask());
 214             }
 215         }
 216     }
 217 }
 218
 219 void CameraGroup::setCameraParameters(float vfov, float aspectRatio)
 220 {
 221     _viewer->getCamera()->setProjectionMatrixAsPerspective(vfov,
 222                                                            1.0f / aspectRatio,
 223                                                            _zNear, _zFar);
 224 }
 225 }
 226
 227 namespace
 228 {
 229 // A raw value for property nodes that references a class member via
 230 // an osg::ref_ptr.
 231 template<class C, class T>
 232 class RefMember : public SGRawValue<T>
 233 {
 234 public:
 235     RefMember (C *obj, T C::*ptr)
 236         : _obj(obj), _ptr(ptr) {}
 237     virtual ~RefMember () {}
 238     virtual T getValue () const
 239     {
 240         return _obj.get()->*_ptr;
 241     }
 242     virtual bool setValue (T value)
 243     {
 244         _obj.get()->*_ptr = value;
 245         return true;
 246     }
 247     virtual SGRawValue<T> * clone () const
 248     {
 249         return new RefMember(_obj.get(), _ptr);
 250     }
 251 private:
 252     ref_ptr<C> _obj;
 253     T C::* const _ptr;
 254 };
 255
 256 template<typename C, typename T>
 257 RefMember<C, T> makeRefMember(C *obj, T C::*ptr)
 258 {
 259     return RefMember<C, T>(obj, ptr);
 260 }
 261
 262 template<typename C, typename T>
 263 void bindMemberToNode(SGPropertyNode* parent, const char* childName,
 264                       C* obj, T C::*ptr, T value)
 265 {
 266     SGPropertyNode* valNode = parent->getNode(childName);
 267     RefMember<C, T> refMember = makeRefMember(obj, ptr);
 268     if (!valNode) {
 269         valNode = parent->getNode(childName, true);
 270         valNode->tie(refMember, false);
 271         setValue(valNode, value);
 272     } else {
 273         valNode->tie(refMember, true);
 274     }
 275 }
 276
 277 void buildViewport(flightgear::CameraInfo* info, SGPropertyNode* viewportNode,
 278                    const osg::GraphicsContext::Traits *traits)
 279 {
 280     using namespace flightgear;
 281     bindMemberToNode(viewportNode, "x", info, &CameraInfo::x, 0.0);
 282     bindMemberToNode(viewportNode, "y", info, &CameraInfo::y, 0.0);
 283     bindMemberToNode(viewportNode, "width", info, &CameraInfo::width,
 284                      static_cast<double>(traits->width));
 285     bindMemberToNode(viewportNode, "height", info, &CameraInfo::height,
 286                      static_cast<double>(traits->height));
 287 }
 288 }
 289
 290 namespace flightgear
 291 {
 292
 293 CameraInfo* CameraGroup::buildCamera(SGPropertyNode* cameraNode)
 294 {
 295     WindowBuilder *wBuild = WindowBuilder::getWindowBuilder();
 296     const SGPropertyNode* windowNode = cameraNode->getNode("window");
 297     GraphicsWindow* window = 0;
 298     static int cameraNum = 0;
 299     int cameraFlags = DO_INTERSECTION_TEST;
 300     if (windowNode) {
 301         // New style window declaration / definition
 302         window = wBuild->buildWindow(windowNode);
 303     } else {
 304         // Old style: suck window params out of camera block
 305         window = wBuild->buildWindow(cameraNode);
 306     }
 307     if (!window) {
 308         return 0;
 309     }
 310     Camera* camera = new Camera;
 311     camera->setAllowEventFocus(false);
 312     camera->setGraphicsContext(window->gc.get());
 313     camera->setViewport(new Viewport);
 314     camera->setCullingMode(CullSettings::SMALL_FEATURE_CULLING
 315                            | CullSettings::VIEW_FRUSTUM_CULLING);
 316     camera->setInheritanceMask(CullSettings::ALL_VARIABLES
 317                                & ~(CullSettings::CULL_MASK
 318                                    | CullSettings::CULLING_MODE));
 319
 320     osg::Matrix pOff;
 321     osg::Matrix vOff;
 322     const SGPropertyNode* viewNode = cameraNode->getNode("view");
 323     if (viewNode) {
 324         double heading = viewNode->getDoubleValue("heading-deg", 0.0);
 325         double pitch = viewNode->getDoubleValue("pitch-deg", 0.0);
 326         double roll = viewNode->getDoubleValue("roll-deg", 0.0);
 327         double x = viewNode->getDoubleValue("x", 0.0);
 328         double y = viewNode->getDoubleValue("y", 0.0);
 329         double z = viewNode->getDoubleValue("z", 0.0);
 330         // Build a view matrix, which is the inverse of a model
 331         // orientation matrix.
 332         vOff = (Matrix::translate(-x, -y, -z)
 333                 * Matrix::rotate(-DegreesToRadians(heading),
 334                                  Vec3d(0.0, 1.0, 0.0),
 335                                  -DegreesToRadians(pitch),
 336                                  Vec3d(1.0, 0.0, 0.0),
 337                                  -DegreesToRadians(roll),
 338                                  Vec3d(0.0, 0.0, 1.0)));
 339         if (viewNode->getBoolValue("absolute", false))
 340             cameraFlags |= VIEW_ABSOLUTE;
 341     } else {
 342         // Old heading parameter, works in the opposite direction
 343         double heading = cameraNode->getDoubleValue("heading-deg", 0.0);
 344         vOff.makeRotate(DegreesToRadians(heading), osg::Vec3(0, 1, 0));
 345     }
 346     const SGPropertyNode* projectionNode = 0;
 347     if ((projectionNode = cameraNode->getNode("perspective")) != 0) {
 348         double fovy = projectionNode->getDoubleValue("fovy-deg", 55.0);
 349         double aspectRatio = projectionNode->getDoubleValue("aspect-ratio",
 350                                                             1.0);
 351         double zNear = projectionNode->getDoubleValue("near", 0.0);
 352         double zFar = projectionNode->getDoubleValue("far", 0.0);
 353         double offsetX = projectionNode->getDoubleValue("offset-x", 0.0);
 354         double offsetY = projectionNode->getDoubleValue("offset-y", 0.0);
 355         double tan_fovy = tan(DegreesToRadians(fovy*0.5));
 356         double right = tan_fovy * aspectRatio * zNear + offsetX;
 357         double left = -tan_fovy * aspectRatio * zNear + offsetX;
 358         double top = tan_fovy * zNear + offsetY;
 359         double bottom = -tan_fovy * zNear + offsetY;
 360         pOff.makeFrustum(left, right, bottom, top, zNear, zFar);
 361         cameraFlags |= PROJECTION_ABSOLUTE;
 362     } else if ((projectionNode = cameraNode->getNode("frustum")) != 0
 363                || (projectionNode = cameraNode->getNode("ortho")) != 0) {
 364         double top = projectionNode->getDoubleValue("top", 0.0);
 365         double bottom = projectionNode->getDoubleValue("bottom", 0.0);
 366         double left = projectionNode->getDoubleValue("left", 0.0);
 367         double right = projectionNode->getDoubleValue("right", 0.0);
 368         double zNear = projectionNode->getDoubleValue("near", 0.0);
 369         double zFar = projectionNode->getDoubleValue("far", 0.0);
 370         if (cameraNode->getNode("frustum")) {
 371             pOff.makeFrustum(left, right, bottom, top, zNear, zFar);
 372             cameraFlags |= PROJECTION_ABSOLUTE;
 373         } else {
 374             pOff.makeOrtho(left, right, bottom, top, zNear, zFar);
 375             cameraFlags |= (PROJECTION_ABSOLUTE | ORTHO);
 376         }
 377     } else {
 378         // old style shear parameters
 379         double shearx = cameraNode->getDoubleValue("shear-x", 0);
 380         double sheary = cameraNode->getDoubleValue("shear-y", 0);
 381         pOff.makeTranslate(-shearx, -sheary, 0);
 382     }
 383     CameraInfo* info = addCamera(cameraFlags, camera, pOff, vOff);
 384     // If a viewport isn't set on the camera, then it's hard to dig it
 385     // out of the SceneView objects in the viewer, and the coordinates
 386     // of mouse events are somewhat bizzare.
 387     SGPropertyNode* viewportNode = cameraNode->getNode("viewport", true);
 388     buildViewport(info, viewportNode, window->gc->getTraits());
 389     updateCameras(info);
 390     return info;
 391 }
 392
 393 CameraInfo* CameraGroup::buildGUICamera(SGPropertyNode* cameraNode,
 394                                         GraphicsWindow* window)
 395 {
 396     WindowBuilder *wBuild = WindowBuilder::getWindowBuilder();
 397     const SGPropertyNode* windowNode = (cameraNode
 398                                         ? cameraNode->getNode("window")
 399                                         : 0);
 400     static int cameraNum = 0;
 401     if (!window) {
 402         if (windowNode) {
 403             // New style window declaration / definition
 404             window = wBuild->buildWindow(windowNode);
 405
 406         } else {
 407             return 0;
 408         }
 409     }
 410     Camera* camera = new Camera;
 411     camera->setAllowEventFocus(false);
 412     camera->setGraphicsContext(window->gc.get());
 413     camera->setViewport(new Viewport);
 414     // XXX Camera needs to be drawn last; eventually the render order
 415     // should be assigned by a camera manager.
 416     camera->setRenderOrder(osg::Camera::POST_RENDER, 100);
 417         camera->setClearMask(0);
 418     camera->setInheritanceMask(CullSettings::ALL_VARIABLES
 419                                & ~(CullSettings::COMPUTE_NEAR_FAR_MODE
 420                                    | CullSettings::CULLING_MODE));
 421     camera->setComputeNearFarMode(osg::CullSettings::DO_NOT_COMPUTE_NEAR_FAR);
 422     camera->setCullingMode(osg::CullSettings::NO_CULLING);
 423     camera->setProjectionResizePolicy(Camera::FIXED);
 424     camera->setReferenceFrame(Transform::ABSOLUTE_RF);
 425     const int cameraFlags = GUI;
 426     CameraInfo* result = addCamera(cameraFlags, camera, Matrixd::identity(),
 427                                    Matrixd::identity(), false);
 428     SGPropertyNode* viewportNode = cameraNode->getNode("viewport", true);
 429     buildViewport(result, viewportNode, window->gc->getTraits());
 430
 431     // Disable statistics for the GUI camera.
 432     result->camera->setStats(0);
 433     updateCameras(result);
 434     return result;
 435 }
 436
 437 CameraGroup* CameraGroup::buildCameraGroup(osgViewer::Viewer* viewer,
 438                                            SGPropertyNode* gnode)
 439 {
 440     CameraGroup* cgroup = new CameraGroup(viewer);
 441     for (int i = 0; i < gnode->nChildren(); ++i) {
 442         SGPropertyNode* pNode = gnode->getChild(i);
 443         const char* name = pNode->getName();
 444         if (!strcmp(name, "camera")) {
 445             cgroup->buildCamera(pNode);
 446         } else if (!strcmp(name, "window")) {
 447             WindowBuilder::getWindowBuilder()->buildWindow(pNode);
 448         } else if (!strcmp(name, "gui")) {
 449             cgroup->buildGUICamera(pNode);
 450         }
 451     }
 452     bindMemberToNode(gnode, "znear", cgroup, &CameraGroup::_zNear, .4f);
 453     bindMemberToNode(gnode, "zfar", cgroup, &CameraGroup::_zFar, 120000.0f);
 454     bindMemberToNode(gnode, "near-field", cgroup, &CameraGroup::_nearField,
 455                      100.0f);
 456     return cgroup;
 457 }
 458
 459 void CameraGroup::setCameraCullMasks(Node::NodeMask nm)
 460 {
 461     for (CameraIterator i = camerasBegin(), e = camerasEnd(); i != e; ++i) {
 462         CameraInfo* info = i->get();
 463         if (info->flags & GUI)
 464             continue;
 465         if (info->farCamera.valid() && info->farCamera->getNodeMask() != 0) {
 466             info->camera->setCullMask(nm & ~simgear::BACKGROUND_BIT);
 467             info->farCamera->setCullMask(nm);
 468         } else {
 469             info->camera->setCullMask(nm);
 470         }
 471     }
 472 }
 473
 474 void CameraGroup::resized()
 475 {
 476     for (CameraIterator i = camerasBegin(), e = camerasEnd(); i != e; ++i) {
 477         CameraInfo *info = i->get();
 478         const Viewport* viewport = info->camera->getViewport();
 479         info->x = viewport->x();
 480         info->y = viewport->y();
 481         info->width = viewport->width();
 482         info->height = viewport->height();
 483     }
 484 }
 485
 486 Camera* getGUICamera(CameraGroup* cgroup)
 487 {
 488     CameraGroup::CameraIterator end = cgroup->camerasEnd();
 489     CameraGroup::CameraIterator result
 490         = std::find_if(cgroup->camerasBegin(), end,
 491                        FlagTester<CameraInfo>(CameraGroup::GUI));
 492     if (result != end)
 493         return (*result)->camera.get();
 494     else
 495         return 0;
 496 }
 497
 498 bool computeIntersections(const CameraGroup* cgroup,
 499                           const osgGA::GUIEventAdapter* ea,
 500                           osgUtil::LineSegmentIntersector::Intersections& intersections)
 501 {
 502     using osgUtil::Intersector;
 503     using osgUtil::LineSegmentIntersector;
 504     double x, y;
 505     eventToWindowCoords(ea, x, y);
 506     // Find camera that contains event
 507     for (CameraGroup::ConstCameraIterator iter = cgroup->camerasBegin(),
 508              e = cgroup->camerasEnd();
 509          iter != e;
 510          ++iter) {
 511         const CameraInfo* cinfo = iter->get();
 512         if ((cinfo->flags & CameraGroup::DO_INTERSECTION_TEST) == 0)
 513             continue;
 514         const Camera* camera = cinfo->camera.get();
 515         if (camera->getGraphicsContext() != ea->getGraphicsContext())
 516             continue;
 517         const Viewport* viewport = camera->getViewport();
 518         double epsilon = 0.5;
 519         if (!(x >= viewport->x() - epsilon
 520               && x < viewport->x() + viewport->width() -1.0 + epsilon
 521               && y >= viewport->y() - epsilon
 522               && y < viewport->y() + viewport->height() -1.0 + epsilon))
 523             continue;
 524         Vec4d start(x, y, 0.0, 1.0);
 525         Vec4d end(x, y, 1.0, 1.0);
 526         Matrix windowMat = viewport->computeWindowMatrix();
 527         Matrix startPtMat = Matrix::inverse(camera->getProjectionMatrix()
 528                                             * windowMat);
 529         Matrix endPtMat;
 530         if (!cinfo->farCamera.valid() || cinfo->farCamera->getNodeMask() == 0)
 531             endPtMat = startPtMat;
 532         else
 533             endPtMat = Matrix::inverse(cinfo->farCamera->getProjectionMatrix()
 534                                        * windowMat);
 535         start = start * startPtMat;
 536         start /= start.w();
 537         end = end * endPtMat;
 538         end /= end.w();
 539         ref_ptr<LineSegmentIntersector> picker
 540             = new LineSegmentIntersector(Intersector::VIEW,
 541                                          Vec3d(start.x(), start.y(), start.z()),
 542                                          Vec3d(end.x(), end.y(), end.z()));
 543         osgUtil::IntersectionVisitor iv(picker.get());
 544         const_cast<Camera*>(camera)->accept(iv);
 545         if (picker->containsIntersections()) {
 546             intersections = picker->getIntersections();
 547             return true;
 548         } else {
 549             break;
 550         }
 551     }
 552     intersections.clear();
 553     return false;
 554 }
 555
 556 void warpGUIPointer(CameraGroup* cgroup, int x, int y)
 557 {
 558     using osgViewer::GraphicsWindow;
 559     Camera* guiCamera = getGUICamera(cgroup);
 560     if (!guiCamera)
 561         return;
 562     Viewport* vport = guiCamera->getViewport();
 563     GraphicsWindow* gw
 564         = dynamic_cast<GraphicsWindow*>(guiCamera->getGraphicsContext());
 565     if (!gw)
 566         return;
 567     globals->get_renderer()->getEventHandler()->setMouseWarped();
 568     // Translate the warp request into the viewport of the GUI camera,
 569     // send the request to the window, then transform the coordinates
 570     // for the Viewer's event queue.
 571     double wx = x + vport->x();
 572     double wyUp = vport->height() + vport->y() - y;
 573     double wy;
 574     const GraphicsContext::Traits* traits = gw->getTraits();
 575     if (gw->getEventQueue()->getCurrentEventState()->getMouseYOrientation()
 576         == osgGA::GUIEventAdapter::Y_INCREASING_DOWNWARDS) {
 577         wy = traits->height - wyUp;
 578     } else {
 579         wy = wyUp;
 580     }
 581     gw->getEventQueue()->mouseWarped(wx, wy);
 582     gw->requestWarpPointer(wx, wy);
 583     osgGA::GUIEventAdapter* eventState
 584         = cgroup->getViewer()->getEventQueue()->getCurrentEventState();
 585     double viewerX
 586         = (eventState->getXmin()
 587            + ((wx / double(traits->width))
 588               * (eventState->getXmax() - eventState->getXmin())));
 589     double viewerY
 590         = (eventState->getYmin()
 591            + ((wyUp / double(traits->height))
 592               * (eventState->getYmax() - eventState->getYmin())));
 593     cgroup->getViewer()->getEventQueue()->mouseWarped(viewerX, viewerY);
 594 }
 595 }