src/Main/CameraGroup.cxx

   1 // Copyright (C) 2008  Tim Moore
   2 // Copyright (C) 2011  Mathias Froehlich
   3 //
   4 // This program is free software; you can redistribute it and/or
   5 // modify it under the terms of the GNU General Public License as
   6 // published by the Free Software Foundation; either version 2 of the
   7 // License, or (at your option) any later version.
   8 //
   9 // This program is distributed in the hope that it will be useful, but
  10 // WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12 // General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with this program; if not, write to the Free Software
  16 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  17
  18 #ifdef HAVE_CONFIG_H
  19 #  include <config.h>
  20 #endif
  21
  22 #include "CameraGroup.hxx"
  23
  24 #include "fg_props.hxx"
  25 #include "globals.hxx"
  26 #include "renderer.hxx"
  27 #include "FGEventHandler.hxx"
  28 #include "WindowBuilder.hxx"
  29 #include "WindowSystemAdapter.hxx"
  30 #include <simgear/props/props.hxx>
  31 #include <simgear/structure/OSGUtils.hxx>
  32 #include <simgear/structure/OSGVersion.hxx>
  33 #include <simgear/scene/material/EffectCullVisitor.hxx>
  34 #include <simgear/scene/util/RenderConstants.hxx>
  35
  36 #include <algorithm>
  37 #include <cstring>
  38 #include <string>
  39
  40 #include <osg/Camera>
  41 #include <osg/Geometry>
  42 #include <osg/GraphicsContext>
  43 #include <osg/io_utils>
  44 #include <osg/Math>
  45 #include <osg/Matrix>
  46 #include <osg/Notify>
  47 #include <osg/Program>
  48 #include <osg/Quat>
  49 #include <osg/TexMat>
  50 #include <osg/Vec3d>
  51 #include <osg/Viewport>
  52
  53 #include <osgUtil/IntersectionVisitor>
  54
  55 #include <osgViewer/GraphicsWindow>
  56 #include <osgViewer/Renderer>
  57
  58 static osg::Matrix
  59 invert(const osg::Matrix& matrix)
  60 {
  61     return osg::Matrix::inverse(matrix);
  62 }
  63
  64 /// Returns the zoom factor of the master camera.
  65 /// The reference fov is the historic 55 deg
  66 static double
  67 zoomFactor()
  68 {
  69     double fov = fgGetDouble("/sim/current-view/field-of-view", 55);
  70     if (fov < 1)
  71         fov = 1;
  72     return tan(55*0.5*SG_DEGREES_TO_RADIANS)/tan(fov*0.5*SG_DEGREES_TO_RADIANS);
  73 }
  74
  75 static osg::Vec2d
  76 preMult(const osg::Vec2d& v, const osg::Matrix& m)
  77 {
  78   osg::Vec3d tmp = m.preMult(osg::Vec3(v, 0));
  79   return osg::Vec2d(tmp[0], tmp[1]);
  80 }
  81
  82 static osg::Matrix
  83 relativeProjection(const osg::Matrix& P0, const osg::Matrix& R, const osg::Vec2d ref[2],
  84                    const osg::Matrix& pP, const osg::Matrix& pR, const osg::Vec2d pRef[2])
  85 {
  86   // Track the way from one projection space to the other:
  87   // We want
  88   //  P = T*S*P0
  89   // where P0 is the projection template sensible for the given window size,
  90   // T is a translation matrix and S a scale matrix.
  91   // We need to determine T and S so that the reference points in the parents
  92   // projection space match the two reference points in this cameras projection space.
  93
  94   // Starting from the parents camera projection space, we get into this cameras
  95   // projection space by the transform matrix:
  96   //  P*R*inv(pP*pR) = T*S*P0*R*inv(pP*pR)
  97   // So, at first compute that matrix without T*S and determine S and T from that
  98
  99   // Ok, now osg uses the inverse matrix multiplication order, thus:
 100   osg::Matrix PtoPwithoutTS = invert(pR*pP)*R*P0;
 101   // Compute the parents reference points in the current projection space
 102   // without the yet unknown T and S
 103   osg::Vec2d pRefInThis[2] = {
 104     preMult(pRef[0], PtoPwithoutTS),
 105     preMult(pRef[1], PtoPwithoutTS)
 106   };
 107
 108   // To get the same zoom, rescale to match the parents size
 109   double s = (ref[0] - ref[1]).length()/(pRefInThis[0] - pRefInThis[1]).length();
 110   osg::Matrix S = osg::Matrix::scale(s, s, 1);
 111
 112   // For the translation offset, incorporate the now known scale
 113   // and recompute the position ot the first reference point in the
 114   // currents projection space without the yet unknown T.
 115   pRefInThis[0] = preMult(pRef[0], PtoPwithoutTS*S);
 116   // The translation is then the difference of the reference points
 117   osg::Matrix T = osg::Matrix::translate(osg::Vec3d(ref[0] - pRefInThis[0], 0));
 118
 119   // Compose and return the desired final projection matrix
 120   return P0*S*T;
 121 }
 122
 123 namespace flightgear
 124 {
 125 using namespace osg;
 126
 127 using std::strcmp;
 128 using std::string;
 129
 130 ref_ptr<CameraGroup> CameraGroup::_defaultGroup;
 131
 132 CameraGroup::CameraGroup(osgViewer::Viewer* viewer) :
 133     _viewer(viewer)
 134 {
 135 }
 136
 137 }
 138
 139 namespace
 140 {
 141 using namespace osg;
 142
 143 // Given a projection matrix, return a new one with the same frustum
 144 // sides and new near / far values.
 145
 146 void makeNewProjMat(Matrixd& oldProj, double znear,
 147                                        double zfar, Matrixd& projection)
 148 {
 149     projection = oldProj;
 150     // Slightly inflate the near & far planes to avoid objects at the
 151     // extremes being clipped out.
 152     znear *= 0.999;
 153     zfar *= 1.001;
 154
 155     // Clamp the projection matrix z values to the range (near, far)
 156     double epsilon = 1.0e-6;
 157     if (fabs(projection(0,3)) < epsilon &&
 158         fabs(projection(1,3)) < epsilon &&
 159         fabs(projection(2,3)) < epsilon) {
 160         // Projection is Orthographic
 161         epsilon = -1.0/(zfar - znear); // Used as a temp variable
 162         projection(2,2) = 2.0*epsilon;
 163         projection(3,2) = (zfar + znear)*epsilon;
 164     } else {
 165         // Projection is Perspective
 166         double trans_near = (-znear*projection(2,2) + projection(3,2)) /
 167             (-znear*projection(2,3) + projection(3,3));
 168         double trans_far = (-zfar*projection(2,2) + projection(3,2)) /
 169             (-zfar*projection(2,3) + projection(3,3));
 170         double ratio = fabs(2.0/(trans_near - trans_far));
 171         double center = -0.5*(trans_near + trans_far);
 172
 173         projection.postMult(osg::Matrixd(1.0, 0.0, 0.0, 0.0,
 174                                          0.0, 1.0, 0.0, 0.0,
 175                                          0.0, 0.0, ratio, 0.0,
 176                                          0.0, 0.0, center*ratio, 1.0));
 177     }
 178 }
 179
 180 void installCullVisitor(Camera* camera)
 181 {
 182     osgViewer::Renderer* renderer
 183         = static_cast<osgViewer::Renderer*>(camera->getRenderer());
 184     for (int i = 0; i < 2; ++i) {
 185         osgUtil::SceneView* sceneView = renderer->getSceneView(i);
 186 #if SG_OSG_VERSION_LESS_THAN(3,0,0)
 187         sceneView->setCullVisitor(new simgear::EffectCullVisitor);
 188 #else
 189         osg::ref_ptr<osgUtil::CullVisitor::Identifier> identifier;
 190         identifier = sceneView->getCullVisitor()->getIdentifier();
 191         sceneView->setCullVisitor(new simgear::EffectCullVisitor);
 192         sceneView->getCullVisitor()->setIdentifier(identifier.get());
 193
 194         identifier = sceneView->getCullVisitorLeft()->getIdentifier();
 195         sceneView->setCullVisitorLeft(sceneView->getCullVisitor()->clone());
 196         sceneView->getCullVisitorLeft()->setIdentifier(identifier.get());
 197
 198         identifier = sceneView->getCullVisitorRight()->getIdentifier();
 199         sceneView->setCullVisitorRight(sceneView->getCullVisitor()->clone());
 200         sceneView->getCullVisitorRight()->setIdentifier(identifier.get());
 201 #endif
 202     }
 203 }
 204 }
 205
 206 namespace flightgear
 207 {
 208 void updateCameras(const CameraInfo* info)
 209 {
 210     if (info->camera.valid())
 211         info->camera->getViewport()->setViewport(info->x, info->y,
 212                                                  info->width, info->height);
 213     if (info->farCamera.valid())
 214         info->farCamera->getViewport()->setViewport(info->x, info->y,
 215                                                     info->width, info->height);
 216 }
 217
 218 CameraInfo* CameraGroup::addCamera(unsigned flags, Camera* camera,
 219                                    const Matrix& view,
 220                                    const Matrix& projection,
 221                                    bool useMasterSceneData)
 222 {
 223     CameraInfo* info = new CameraInfo(flags);
 224     // The camera group will always update the camera
 225     camera->setReferenceFrame(Transform::ABSOLUTE_RF);
 226
 227     Camera* farCamera = 0;
 228     if ((flags & (GUI | ORTHO)) == 0) {
 229         farCamera = new Camera;
 230         farCamera->setAllowEventFocus(camera->getAllowEventFocus());
 231         farCamera->setGraphicsContext(camera->getGraphicsContext());
 232         farCamera->setCullingMode(camera->getCullingMode());
 233         farCamera->setInheritanceMask(camera->getInheritanceMask());
 234         farCamera->setReferenceFrame(Transform::ABSOLUTE_RF);
 235         // Each camera's viewport is written when the window is
 236         // resized; if the the viewport isn't copied here, it gets updated
 237         // twice and ends up with the wrong value.
 238         farCamera->setViewport(simgear::clone(camera->getViewport()));
 239         farCamera->setDrawBuffer(camera->getDrawBuffer());
 240         farCamera->setReadBuffer(camera->getReadBuffer());
 241         farCamera->setRenderTargetImplementation(
 242             camera->getRenderTargetImplementation());
 243         const Camera::BufferAttachmentMap& bufferMap
 244             = camera->getBufferAttachmentMap();
 245         if (bufferMap.count(Camera::COLOR_BUFFER) != 0) {
 246             farCamera->attach(
 247                 Camera::COLOR_BUFFER,
 248                 bufferMap.find(Camera::COLOR_BUFFER)->second._texture.get());
 249         }
 250         _viewer->addSlave(farCamera, projection, view, useMasterSceneData);
 251         installCullVisitor(farCamera);
 252         info->farCamera = farCamera;
 253         info->farSlaveIndex = _viewer->getNumSlaves() - 1;
 254         farCamera->setRenderOrder(Camera::POST_RENDER, info->farSlaveIndex);
 255         camera->setCullMask(camera->getCullMask() & ~simgear::BACKGROUND_BIT);
 256         camera->setClearMask(GL_DEPTH_BUFFER_BIT);
 257     }
 258     _viewer->addSlave(camera, projection, view, useMasterSceneData);
 259     installCullVisitor(camera);
 260     info->camera = camera;
 261     info->slaveIndex = _viewer->getNumSlaves() - 1;
 262     camera->setRenderOrder(Camera::POST_RENDER, info->slaveIndex);
 263     _cameras.push_back(info);
 264     return info;
 265 }
 266
 267 void CameraGroup::update(const osg::Vec3d& position,
 268                          const osg::Quat& orientation)
 269 {
 270     const Matrix masterView(osg::Matrix::translate(-position)
 271                             * osg::Matrix::rotate(orientation.inverse()));
 272     _viewer->getCamera()->setViewMatrix(masterView);
 273     const Matrix& masterProj = _viewer->getCamera()->getProjectionMatrix();
 274     double masterZoomFactor = zoomFactor();
 275     for (CameraList::iterator i = _cameras.begin(); i != _cameras.end(); ++i) {
 276         const CameraInfo* info = i->get();
 277         const View::Slave& slave = _viewer->getSlave(info->slaveIndex);
 278 #if SG_OSG_VERSION_LESS_THAN(3,0,0)
 279         // refreshes camera viewports (for now)
 280         updateCameras(info);
 281 #endif
 282         Camera* camera = info->camera.get();
 283         Matrix viewMatrix;
 284
 285         if (info->flags & GUI) {
 286           viewMatrix = osg::Matrix(); // identifty transform on the GUI camera
 287         } else if ((info->flags & VIEW_ABSOLUTE) != 0)
 288             viewMatrix = slave._viewOffset;
 289         else
 290             viewMatrix = masterView * slave._viewOffset;
 291         camera->setViewMatrix(viewMatrix);
 292         Matrix projectionMatrix;
 293
 294         if (info->flags & GUI) {
 295           projectionMatrix = osg::Matrix::ortho2D(0, info->width, 0, info->height);
 296         } else if ((info->flags & PROJECTION_ABSOLUTE) != 0) {
 297             if (info->flags & ENABLE_MASTER_ZOOM) {
 298                 if (info->relativeCameraParent < _cameras.size()) {
 299                     // template projection matrix and view matrix of the current camera
 300                     osg::Matrix P0 = slave._projectionOffset;
 301                     osg::Matrix R = viewMatrix;
 302
 303                     // The already known projection and view matrix of the parent camera
 304                     const CameraInfo* parentInfo = _cameras[info->relativeCameraParent].get();
 305                     osg::Matrix pP = parentInfo->camera->getProjectionMatrix();
 306                     osg::Matrix pR = parentInfo->camera->getViewMatrix();
 307
 308                     // And the projection matrix derived from P0 so that the reference points match
 309                     projectionMatrix = relativeProjection(P0, R, info->thisReference,
 310                                                           pP, pR, info->parentReference);
 311
 312                 } else {
 313                     // We want to zoom, so take the original matrix and apply the zoom to it.
 314                     projectionMatrix = slave._projectionOffset;
 315                     projectionMatrix.postMultScale(osg::Vec3d(masterZoomFactor, masterZoomFactor, 1));
 316                 }
 317             } else {
 318                 projectionMatrix = slave._projectionOffset;
 319             }
 320         } else {
 321             projectionMatrix = masterProj * slave._projectionOffset;
 322         }
 323
 324         if (!info->farCamera.valid()) {
 325             camera->setProjectionMatrix(projectionMatrix);
 326         } else {
 327             Camera* farCamera = info->farCamera.get();
 328             farCamera->setViewMatrix(viewMatrix);
 329             double left, right, bottom, top, parentNear, parentFar;
 330             projectionMatrix.getFrustum(left, right, bottom, top,
 331                                         parentNear, parentFar);
 332             if ((info->flags & FIXED_NEAR_FAR) == 0) {
 333                 parentNear = _zNear;
 334                 parentFar = _zFar;
 335             }
 336             if (parentFar < _nearField || _nearField == 0.0f) {
 337                 camera->setProjectionMatrix(projectionMatrix);
 338                 camera->setCullMask(camera->getCullMask()
 339                                     | simgear::BACKGROUND_BIT);
 340                 camera->setClearMask(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
 341                 farCamera->setNodeMask(0);
 342             } else {
 343                 Matrix nearProj, farProj;
 344                 makeNewProjMat(projectionMatrix, parentNear, _nearField,
 345                                nearProj);
 346                 makeNewProjMat(projectionMatrix, _nearField, parentFar,
 347                                farProj);
 348                 camera->setProjectionMatrix(nearProj);
 349                 camera->setCullMask(camera->getCullMask()
 350                                     & ~simgear::BACKGROUND_BIT);
 351                 camera->setClearMask(GL_DEPTH_BUFFER_BIT);
 352                 farCamera->setProjectionMatrix(farProj);
 353                 farCamera->setNodeMask(camera->getNodeMask());
 354             }
 355         }
 356     }
 357 }
 358
 359 void CameraGroup::setCameraParameters(float vfov, float aspectRatio)
 360 {
 361     if (vfov != 0.0f && aspectRatio != 0.0f)
 362         _viewer->getCamera()
 363             ->setProjectionMatrixAsPerspective(vfov,
 364                                                1.0f / aspectRatio,
 365                                                _zNear, _zFar);
 366 }
 367
 368 double CameraGroup::getMasterAspectRatio() const
 369 {
 370     if (_cameras.empty())
 371         return 0.0;
 372
 373     const CameraInfo* info = _cameras.front();
 374
 375     const osg::Viewport* viewport = info->camera->getViewport();
 376     if (!viewport) {
 377         return 0.0;
 378     }
 379
 380     return static_cast<double>(viewport->height()) / viewport->width();
 381 }
 382
 383 }
 384
 385 namespace
 386 {
 387 // A raw value for property nodes that references a class member via
 388 // an osg::ref_ptr.
 389 template<class C, class T>
 390 class RefMember : public SGRawValue<T>
 391 {
 392 public:
 393     RefMember (C *obj, T C::*ptr)
 394         : _obj(obj), _ptr(ptr) {}
 395     virtual ~RefMember () {}
 396     virtual T getValue () const
 397     {
 398         return _obj.get()->*_ptr;
 399     }
 400     virtual bool setValue (T value)
 401     {
 402         _obj.get()->*_ptr = value;
 403         return true;
 404     }
 405     virtual SGRawValue<T> * clone () const
 406     {
 407         return new RefMember(_obj.get(), _ptr);
 408     }
 409 private:
 410     ref_ptr<C> _obj;
 411     T C::* const _ptr;
 412 };
 413
 414 template<typename C, typename T>
 415 RefMember<C, T> makeRefMember(C *obj, T C::*ptr)
 416 {
 417     return RefMember<C, T>(obj, ptr);
 418 }
 419
 420 template<typename C, typename T>
 421 void bindMemberToNode(SGPropertyNode* parent, const char* childName,
 422                       C* obj, T C::*ptr, T value)
 423 {
 424     SGPropertyNode* valNode = parent->getNode(childName);
 425     RefMember<C, T> refMember = makeRefMember(obj, ptr);
 426     if (!valNode) {
 427         valNode = parent->getNode(childName, true);
 428         valNode->tie(refMember, false);
 429         setValue(valNode, value);
 430     } else {
 431         valNode->tie(refMember, true);
 432     }
 433 }
 434
 435 void buildViewport(flightgear::CameraInfo* info, SGPropertyNode* viewportNode,
 436                    const osg::GraphicsContext::Traits *traits)
 437 {
 438     using namespace flightgear;
 439     bindMemberToNode(viewportNode, "x", info, &CameraInfo::x, 0.0);
 440     bindMemberToNode(viewportNode, "y", info, &CameraInfo::y, 0.0);
 441     bindMemberToNode(viewportNode, "width", info, &CameraInfo::width,
 442                      static_cast<double>(traits->width));
 443     bindMemberToNode(viewportNode, "height", info, &CameraInfo::height,
 444                      static_cast<double>(traits->height));
 445 }
 446 }
 447
 448 namespace flightgear
 449 {
 450
 451 // Mostly copied from osg's osgViewer/View.cpp
 452
 453 static osg::Geometry* createParoramicSphericalDisplayDistortionMesh(
 454     const Vec3& origin, const Vec3& widthVector, const Vec3& heightVector,
 455     double sphere_radius, double collar_radius,
 456     Image* intensityMap = 0, const Matrix& projectorMatrix = Matrix())
 457 {
 458     osg::Vec3d center(0.0,0.0,0.0);
 459     osg::Vec3d eye(0.0,0.0,0.0);
 460
 461     double distance = sqrt(sphere_radius*sphere_radius - collar_radius*collar_radius);
 462     bool flip = false;
 463     bool texcoord_flip = false;
 464
 465 #if 0
 466     osg::Vec3d projector = eye - osg::Vec3d(0.0,0.0, distance);
 467
 468     OSG_INFO<<"createParoramicSphericalDisplayDistortionMesh : Projector position = "<<projector<<std::endl;
 469     OSG_INFO<<"createParoramicSphericalDisplayDistortionMesh : distance = "<<distance<<std::endl;
 470 #endif
 471     // create the quad to visualize.
 472     osg::Geometry* geometry = new osg::Geometry();
 473
 474     geometry->setSupportsDisplayList(false);
 475
 476     osg::Vec3 xAxis(widthVector);
 477     float width = widthVector.length();
 478     xAxis /= width;
 479
 480     osg::Vec3 yAxis(heightVector);
 481     float height = heightVector.length();
 482     yAxis /= height;
 483
 484     int noSteps = 160;
 485
 486     osg::Vec3Array* vertices = new osg::Vec3Array;
 487     osg::Vec2Array* texcoords0 = new osg::Vec2Array;
 488     osg::Vec2Array* texcoords1 = intensityMap==0 ? new osg::Vec2Array : 0;
 489     osg::Vec4Array* colors = new osg::Vec4Array;
 490
 491 #if 0
 492     osg::Vec3 bottom = origin;
 493     osg::Vec3 dx = xAxis*(width/((float)(noSteps-2)));
 494     osg::Vec3 dy = yAxis*(height/((float)(noSteps-1)));
 495 #endif
 496     osg::Vec3 top = origin + yAxis*height;
 497
 498     osg::Vec3 screenCenter = origin + widthVector*0.5f + heightVector*0.5f;
 499     float screenRadius = heightVector.length() * 0.5f;
 500
 501     geometry->getOrCreateStateSet()->setMode(GL_CULL_FACE, osg::StateAttribute::OFF | osg::StateAttribute::PROTECTED);
 502
 503     for(int i=0;i<noSteps;++i)
 504     {
 505         //osg::Vec3 cursor = bottom+dy*(float)i;
 506         for(int j=0;j<noSteps;++j)
 507         {
 508             osg::Vec2 texcoord(double(i)/double(noSteps-1), double(j)/double(noSteps-1));
 509             double theta = texcoord.x() * 2.0 * osg::PI;
 510             double phi = (1.0-texcoord.y()) * osg::PI;
 511
 512             if (texcoord_flip) texcoord.y() = 1.0f - texcoord.y();
 513
 514             osg::Vec3 pos(sin(phi)*sin(theta), sin(phi)*cos(theta), cos(phi));
 515             pos = pos*projectorMatrix;
 516
 517             double alpha = atan2(pos.x(), pos.y());
 518             if (alpha<0.0) alpha += 2.0*osg::PI;
 519
 520             double beta = atan2(sqrt(pos.x()*pos.x() + pos.y()*pos.y()), pos.z());
 521             if (beta<0.0) beta += 2.0*osg::PI;
 522
 523             double gamma = atan2(sqrt(double(pos.x()*pos.x() + pos.y()*pos.y())), double(pos.z()+distance));
 524             if (gamma<0.0) gamma += 2.0*osg::PI;
 525
 526
 527             osg::Vec3 v = screenCenter + osg::Vec3(sin(alpha)*gamma*2.0/osg::PI, -cos(alpha)*gamma*2.0/osg::PI, 0.0f)*screenRadius;
 528
 529             if (flip)
 530                 vertices->push_back(osg::Vec3(v.x(), top.y()-(v.y()-origin.y()),v.z()));
 531             else
 532                 vertices->push_back(v);
 533
 534             texcoords0->push_back( texcoord );
 535
 536             osg::Vec2 texcoord1(alpha/(2.0*osg::PI), 1.0f - beta/osg::PI);
 537             if (intensityMap)
 538             {
 539                 colors->push_back(intensityMap->getColor(texcoord1));
 540             }
 541             else
 542             {
 543                 colors->push_back(osg::Vec4(1.0f,1.0f,1.0f,1.0f));
 544                 if (texcoords1) texcoords1->push_back( texcoord1 );
 545             }
 546
 547
 548         }
 549     }
 550
 551
 552     // pass the created vertex array to the points geometry object.
 553     geometry->setVertexArray(vertices);
 554
 555     geometry->setColorArray(colors);
 556     geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 557
 558     geometry->setTexCoordArray(0,texcoords0);
 559     if (texcoords1) geometry->setTexCoordArray(1,texcoords1);
 560
 561     osg::DrawElementsUShort* elements = new osg::DrawElementsUShort(osg::PrimitiveSet::TRIANGLES);
 562     geometry->addPrimitiveSet(elements);
 563
 564     for(int i=0;i<noSteps-1;++i)
 565     {
 566         for(int j=0;j<noSteps-1;++j)
 567         {
 568             int i1 = j+(i+1)*noSteps;
 569             int i2 = j+(i)*noSteps;
 570             int i3 = j+1+(i)*noSteps;
 571             int i4 = j+1+(i+1)*noSteps;
 572
 573             osg::Vec3& v1 = (*vertices)[i1];
 574             osg::Vec3& v2 = (*vertices)[i2];
 575             osg::Vec3& v3 = (*vertices)[i3];
 576             osg::Vec3& v4 = (*vertices)[i4];
 577
 578             if ((v1-screenCenter).length()>screenRadius) continue;
 579             if ((v2-screenCenter).length()>screenRadius) continue;
 580             if ((v3-screenCenter).length()>screenRadius) continue;
 581             if ((v4-screenCenter).length()>screenRadius) continue;
 582
 583             elements->push_back(i1);
 584             elements->push_back(i2);
 585             elements->push_back(i3);
 586
 587             elements->push_back(i1);
 588             elements->push_back(i3);
 589             elements->push_back(i4);
 590         }
 591     }
 592
 593     return geometry;
 594 }
 595
 596 void CameraGroup::buildDistortionCamera(const SGPropertyNode* psNode,
 597                                         Camera* camera)
 598 {
 599     const SGPropertyNode* texNode = psNode->getNode("texture");
 600     if (!texNode) {
 601         // error
 602         return;
 603     }
 604     string texName = texNode->getStringValue();
 605     TextureMap::iterator itr = _textureTargets.find(texName);
 606     if (itr == _textureTargets.end()) {
 607         // error
 608         return;
 609     }
 610     Viewport* viewport = camera->getViewport();
 611     float width = viewport->width();
 612     float height = viewport->height();
 613     TextureRectangle* texRect = itr->second.get();
 614     double radius = psNode->getDoubleValue("radius", 1.0);
 615     double collar = psNode->getDoubleValue("collar", 0.45);
 616     Geode* geode = new Geode();
 617     geode->addDrawable(createParoramicSphericalDisplayDistortionMesh(
 618                            Vec3(0.0f,0.0f,0.0f), Vec3(width,0.0f,0.0f),
 619                            Vec3(0.0f,height,0.0f), radius, collar));
 620
 621     // new we need to add the texture to the mesh, we do so by creating a
 622     // StateSet to contain the Texture StateAttribute.
 623     StateSet* stateset = geode->getOrCreateStateSet();
 624     stateset->setTextureAttributeAndModes(0, texRect, StateAttribute::ON);
 625     stateset->setMode(GL_LIGHTING, StateAttribute::OFF);
 626
 627     TexMat* texmat = new TexMat;
 628     texmat->setScaleByTextureRectangleSize(true);
 629     stateset->setTextureAttributeAndModes(0, texmat, osg::StateAttribute::ON);
 630 #if 0
 631     if (!applyIntensityMapAsColours && intensityMap)
 632     {
 633         stateset->setTextureAttributeAndModes(1, new osg::Texture2D(intensityMap), osg::StateAttribute::ON);
 634     }
 635 #endif
 636     // add subgraph to render
 637     camera->addChild(geode);
 638     camera->setClearMask(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);
 639     camera->setClearColor(osg::Vec4(0.0, 0.0, 0.0, 1.0));
 640     camera->setComputeNearFarMode(osg::CullSettings::DO_NOT_COMPUTE_NEAR_FAR);
 641     camera->setCullingMode(osg::CullSettings::NO_CULLING);
 642     camera->setName("DistortionCorrectionCamera");
 643 }
 644
 645 CameraInfo* CameraGroup::buildCamera(SGPropertyNode* cameraNode)
 646 {
 647     WindowBuilder *wBuild = WindowBuilder::getWindowBuilder();
 648     const SGPropertyNode* windowNode = cameraNode->getNode("window");
 649     GraphicsWindow* window = 0;
 650     int cameraFlags = DO_INTERSECTION_TEST;
 651     if (windowNode) {
 652         // New style window declaration / definition
 653         window = wBuild->buildWindow(windowNode);
 654     } else {
 655         // Old style: suck window params out of camera block
 656         window = wBuild->buildWindow(cameraNode);
 657     }
 658     if (!window) {
 659         return 0;
 660     }
 661     Camera* camera = new Camera;
 662     camera->setAllowEventFocus(false);
 663     camera->setGraphicsContext(window->gc.get());
 664     camera->setViewport(new Viewport);
 665     camera->setCullingMode(CullSettings::SMALL_FEATURE_CULLING
 666                            | CullSettings::VIEW_FRUSTUM_CULLING);
 667     camera->setInheritanceMask(CullSettings::ALL_VARIABLES
 668                                & ~(CullSettings::CULL_MASK
 669                                    | CullSettings::CULLING_MODE
 670 #if defined(HAVE_CULLSETTINGS_CLEAR_MASK)
 671                                    | CullSettings::CLEAR_MASK
 672 #endif
 673                                    ));
 674
 675     osg::Matrix vOff;
 676     const SGPropertyNode* viewNode = cameraNode->getNode("view");
 677     if (viewNode) {
 678         double heading = viewNode->getDoubleValue("heading-deg", 0.0);
 679         double pitch = viewNode->getDoubleValue("pitch-deg", 0.0);
 680         double roll = viewNode->getDoubleValue("roll-deg", 0.0);
 681         double x = viewNode->getDoubleValue("x", 0.0);
 682         double y = viewNode->getDoubleValue("y", 0.0);
 683         double z = viewNode->getDoubleValue("z", 0.0);
 684         // Build a view matrix, which is the inverse of a model
 685         // orientation matrix.
 686         vOff = (Matrix::translate(-x, -y, -z)
 687                 * Matrix::rotate(-DegreesToRadians(heading),
 688                                  Vec3d(0.0, 1.0, 0.0),
 689                                  -DegreesToRadians(pitch),
 690                                  Vec3d(1.0, 0.0, 0.0),
 691                                  -DegreesToRadians(roll),
 692                                  Vec3d(0.0, 0.0, 1.0)));
 693         if (viewNode->getBoolValue("absolute", false))
 694             cameraFlags |= VIEW_ABSOLUTE;
 695     } else {
 696         // Old heading parameter, works in the opposite direction
 697         double heading = cameraNode->getDoubleValue("heading-deg", 0.0);
 698         vOff.makeRotate(DegreesToRadians(heading), osg::Vec3(0, 1, 0));
 699     }
 700     // Configuring the physical dimensions of a monitor
 701     SGPropertyNode* viewportNode = cameraNode->getNode("viewport", true);
 702     double physicalWidth = viewportNode->getDoubleValue("width", 1024);
 703     double physicalHeight = viewportNode->getDoubleValue("height", 768);
 704     double bezelHeightTop = 0;
 705     double bezelHeightBottom = 0;
 706     double bezelWidthLeft = 0;
 707     double bezelWidthRight = 0;
 708     const SGPropertyNode* physicalDimensionsNode = 0;
 709     if ((physicalDimensionsNode = cameraNode->getNode("physical-dimensions")) != 0) {
 710         physicalWidth = physicalDimensionsNode->getDoubleValue("width", physicalWidth);
 711         physicalHeight = physicalDimensionsNode->getDoubleValue("height", physicalHeight);
 712         const SGPropertyNode* bezelNode = 0;
 713         if ((bezelNode = physicalDimensionsNode->getNode("bezel")) != 0) {
 714             bezelHeightTop = bezelNode->getDoubleValue("top", bezelHeightTop);
 715             bezelHeightBottom = bezelNode->getDoubleValue("bottom", bezelHeightBottom);
 716             bezelWidthLeft = bezelNode->getDoubleValue("left", bezelWidthLeft);
 717             bezelWidthRight = bezelNode->getDoubleValue("right", bezelWidthRight);
 718         }
 719     }
 720     osg::Matrix pOff;
 721     unsigned parentCameraIndex = ~0u;
 722     osg::Vec2d parentReference[2];
 723     osg::Vec2d thisReference[2];
 724     SGPropertyNode* projectionNode = 0;
 725     if ((projectionNode = cameraNode->getNode("perspective")) != 0) {
 726         double fovy = projectionNode->getDoubleValue("fovy-deg", 55.0);
 727         double aspectRatio = projectionNode->getDoubleValue("aspect-ratio",
 728                                                             1.0);
 729         double zNear = projectionNode->getDoubleValue("near", 0.0);
 730         double zFar = projectionNode->getDoubleValue("far", zNear + 20000);
 731         double offsetX = projectionNode->getDoubleValue("offset-x", 0.0);
 732         double offsetY = projectionNode->getDoubleValue("offset-y", 0.0);
 733         double tan_fovy = tan(DegreesToRadians(fovy*0.5));
 734         double right = tan_fovy * aspectRatio * zNear + offsetX;
 735         double left = -tan_fovy * aspectRatio * zNear + offsetX;
 736         double top = tan_fovy * zNear + offsetY;
 737         double bottom = -tan_fovy * zNear + offsetY;
 738         pOff.makeFrustum(left, right, bottom, top, zNear, zFar);
 739         cameraFlags |= PROJECTION_ABSOLUTE;
 740         if (projectionNode->getBoolValue("fixed-near-far", true))
 741             cameraFlags |= FIXED_NEAR_FAR;
 742     } else if ((projectionNode = cameraNode->getNode("frustum")) != 0
 743                || (projectionNode = cameraNode->getNode("ortho")) != 0) {
 744         double top = projectionNode->getDoubleValue("top", 0.0);
 745         double bottom = projectionNode->getDoubleValue("bottom", 0.0);
 746         double left = projectionNode->getDoubleValue("left", 0.0);
 747         double right = projectionNode->getDoubleValue("right", 0.0);
 748         double zNear = projectionNode->getDoubleValue("near", 0.0);
 749         double zFar = projectionNode->getDoubleValue("far", zNear + 20000);
 750         if (cameraNode->getNode("frustum")) {
 751             pOff.makeFrustum(left, right, bottom, top, zNear, zFar);
 752             cameraFlags |= PROJECTION_ABSOLUTE;
 753         } else {
 754             pOff.makeOrtho(left, right, bottom, top, zNear, zFar);
 755             cameraFlags |= (PROJECTION_ABSOLUTE | ORTHO);
 756         }
 757         if (projectionNode->getBoolValue("fixed-near-far", true))
 758             cameraFlags |= FIXED_NEAR_FAR;
 759     } else if ((projectionNode = cameraNode->getNode("master-perspective")) != 0) {
 760         double zNear = projectionNode->getDoubleValue("eye-distance", 0.4*physicalWidth);
 761         double xoff = projectionNode->getDoubleValue("x-offset", 0);
 762         double yoff = projectionNode->getDoubleValue("y-offset", 0);
 763         double left = -0.5*physicalWidth - xoff;
 764         double right = 0.5*physicalWidth - xoff;
 765         double bottom = -0.5*physicalHeight - yoff;
 766         double top = 0.5*physicalHeight - yoff;
 767         pOff.makeFrustum(left, right, bottom, top, zNear, zNear*1000);
 768         cameraFlags |= PROJECTION_ABSOLUTE | ENABLE_MASTER_ZOOM;
 769     } else if ((projectionNode = cameraNode->getNode("right-of-perspective"))
 770                || (projectionNode = cameraNode->getNode("left-of-perspective"))
 771                || (projectionNode = cameraNode->getNode("above-perspective"))
 772                || (projectionNode = cameraNode->getNode("below-perspective"))
 773                || (projectionNode = cameraNode->getNode("reference-points-perspective"))) {
 774         std::string name = projectionNode->getStringValue("parent-camera");
 775         for (unsigned i = 0; i < _cameras.size(); ++i) {
 776             if (_cameras[i]->name != name)
 777                 continue;
 778             parentCameraIndex = i;
 779         }
 780         if (_cameras.size() <= parentCameraIndex) {
 781             SG_LOG(SG_VIEW, SG_ALERT, "CameraGroup::buildCamera: "
 782                    "failed to find parent camera for relative camera!");
 783             return 0;
 784         }
 785         const CameraInfo* parentInfo = _cameras[parentCameraIndex].get();
 786         if (projectionNode->getNameString() == "right-of-perspective") {
 787             double tmp = (parentInfo->physicalWidth + 2*parentInfo->bezelWidthRight)/parentInfo->physicalWidth;
 788             parentReference[0] = osg::Vec2d(tmp, -1);
 789             parentReference[1] = osg::Vec2d(tmp, 1);
 790             tmp = (physicalWidth + 2*bezelWidthLeft)/physicalWidth;
 791             thisReference[0] = osg::Vec2d(-tmp, -1);
 792             thisReference[1] = osg::Vec2d(-tmp, 1);
 793         } else if (projectionNode->getNameString() == "left-of-perspective") {
 794             double tmp = (parentInfo->physicalWidth + 2*parentInfo->bezelWidthLeft)/parentInfo->physicalWidth;
 795             parentReference[0] = osg::Vec2d(-tmp, -1);
 796             parentReference[1] = osg::Vec2d(-tmp, 1);
 797             tmp = (physicalWidth + 2*bezelWidthRight)/physicalWidth;
 798             thisReference[0] = osg::Vec2d(tmp, -1);
 799             thisReference[1] = osg::Vec2d(tmp, 1);
 800         } else if (projectionNode->getNameString() == "above-perspective") {
 801             double tmp = (parentInfo->physicalHeight + 2*parentInfo->bezelHeightTop)/parentInfo->physicalHeight;
 802             parentReference[0] = osg::Vec2d(-1, tmp);
 803             parentReference[1] = osg::Vec2d(1, tmp);
 804             tmp = (physicalHeight + 2*bezelHeightBottom)/physicalHeight;
 805             thisReference[0] = osg::Vec2d(-1, -tmp);
 806             thisReference[1] = osg::Vec2d(1, -tmp);
 807         } else if (projectionNode->getNameString() == "below-perspective") {
 808             double tmp = (parentInfo->physicalHeight + 2*parentInfo->bezelHeightBottom)/parentInfo->physicalHeight;
 809             parentReference[0] = osg::Vec2d(-1, -tmp);
 810             parentReference[1] = osg::Vec2d(1, -tmp);
 811             tmp = (physicalHeight + 2*bezelHeightTop)/physicalHeight;
 812             thisReference[0] = osg::Vec2d(-1, tmp);
 813             thisReference[1] = osg::Vec2d(1, tmp);
 814         } else if (projectionNode->getNameString() == "reference-points-perspective") {
 815             SGPropertyNode* parentNode = projectionNode->getNode("parent", true);
 816             SGPropertyNode* thisNode = projectionNode->getNode("this", true);
 817             SGPropertyNode* pointNode;
 818
 819             pointNode = parentNode->getNode("point", 0, true);
 820             parentReference[0][0] = pointNode->getDoubleValue("x", 0)*2/parentInfo->physicalWidth;
 821             parentReference[0][1] = pointNode->getDoubleValue("y", 0)*2/parentInfo->physicalHeight;
 822             pointNode = parentNode->getNode("point", 1, true);
 823             parentReference[1][0] = pointNode->getDoubleValue("x", 0)*2/parentInfo->physicalWidth;
 824             parentReference[1][1] = pointNode->getDoubleValue("y", 0)*2/parentInfo->physicalHeight;
 825
 826             pointNode = thisNode->getNode("point", 0, true);
 827             thisReference[0][0] = pointNode->getDoubleValue("x", 0)*2/physicalWidth;
 828             thisReference[0][1] = pointNode->getDoubleValue("y", 0)*2/physicalHeight;
 829             pointNode = thisNode->getNode("point", 1, true);
 830             thisReference[1][0] = pointNode->getDoubleValue("x", 0)*2/physicalWidth;
 831             thisReference[1][1] = pointNode->getDoubleValue("y", 0)*2/physicalHeight;
 832         }
 833
 834         pOff = osg::Matrix::perspective(45, physicalWidth/physicalHeight, 1, 20000);
 835         cameraFlags |= PROJECTION_ABSOLUTE | ENABLE_MASTER_ZOOM;
 836     } else {
 837         // old style shear parameters
 838         double shearx = cameraNode->getDoubleValue("shear-x", 0);
 839         double sheary = cameraNode->getDoubleValue("shear-y", 0);
 840         pOff.makeTranslate(-shearx, -sheary, 0);
 841     }
 842     const SGPropertyNode* textureNode = cameraNode->getNode("texture");
 843     if (textureNode) {
 844         string texName = textureNode->getStringValue("name");
 845         int tex_width = textureNode->getIntValue("width");
 846         int tex_height = textureNode->getIntValue("height");
 847         TextureRectangle* texture = new TextureRectangle;
 848
 849         texture->setTextureSize(tex_width, tex_height);
 850         texture->setInternalFormat(GL_RGB);
 851         texture->setFilter(Texture::MIN_FILTER, Texture::LINEAR);
 852         texture->setFilter(Texture::MAG_FILTER, Texture::LINEAR);
 853         texture->setWrap(Texture::WRAP_S, Texture::CLAMP_TO_EDGE);
 854         texture->setWrap(Texture::WRAP_T, Texture::CLAMP_TO_EDGE);
 855         camera->setDrawBuffer(GL_FRONT);
 856         camera->setReadBuffer(GL_FRONT);
 857         camera->setRenderTargetImplementation(Camera::FRAME_BUFFER_OBJECT);
 858         camera->attach(Camera::COLOR_BUFFER, texture);
 859         _textureTargets[texName] = texture;
 860     } else {
 861         camera->setDrawBuffer(GL_BACK);
 862         camera->setReadBuffer(GL_BACK);
 863     }
 864     const SGPropertyNode* psNode = cameraNode->getNode("panoramic-spherical");
 865     bool useMasterSceneGraph = !psNode;
 866     CameraInfo* info = addCamera(cameraFlags, camera, vOff, pOff,
 867                                  useMasterSceneGraph);
 868     info->name = cameraNode->getStringValue("name");
 869     info->physicalWidth = physicalWidth;
 870     info->physicalHeight = physicalHeight;
 871     info->bezelHeightTop = bezelHeightTop;
 872     info->bezelHeightBottom = bezelHeightBottom;
 873     info->bezelWidthLeft = bezelWidthLeft;
 874     info->bezelWidthRight = bezelWidthRight;
 875     info->relativeCameraParent = parentCameraIndex;
 876     info->parentReference[0] = parentReference[0];
 877     info->parentReference[1] = parentReference[1];
 878     info->thisReference[0] = thisReference[0];
 879     info->thisReference[1] = thisReference[1];
 880     // If a viewport isn't set on the camera, then it's hard to dig it
 881     // out of the SceneView objects in the viewer, and the coordinates
 882     // of mouse events are somewhat bizzare.
 883     buildViewport(info, viewportNode, window->gc->getTraits());
 884     updateCameras(info);
 885     // Distortion camera needs the viewport which is created by addCamera().
 886     if (psNode) {
 887         info->flags = info->flags | VIEW_ABSOLUTE;
 888         buildDistortionCamera(psNode, camera);
 889     }
 890     return info;
 891 }
 892
 893 CameraInfo* CameraGroup::buildGUICamera(SGPropertyNode* cameraNode,
 894                                         GraphicsWindow* window)
 895 {
 896     WindowBuilder *wBuild = WindowBuilder::getWindowBuilder();
 897     const SGPropertyNode* windowNode = (cameraNode
 898                                         ? cameraNode->getNode("window")
 899                                         : 0);
 900     if (!window && windowNode) {
 901       // New style window declaration / definition
 902       window = wBuild->buildWindow(windowNode);
 903     }
 904
 905     if (!window) { // buildWindow can fail
 906       SG_LOG(SG_VIEW, SG_WARN, "CameraGroup::buildGUICamera: failed to build a window");
 907       return NULL;
 908     }
 909
 910     Camera* camera = new Camera;
 911     camera->setAllowEventFocus(false);
 912     camera->setGraphicsContext(window->gc.get());
 913     camera->setViewport(new Viewport);
 914     // XXX Camera needs to be drawn last; eventually the render order
 915     // should be assigned by a camera manager.
 916     camera->setRenderOrder(osg::Camera::POST_RENDER, 100);
 917         camera->setClearMask(0);
 918     camera->setInheritanceMask(CullSettings::ALL_VARIABLES
 919                                & ~(CullSettings::COMPUTE_NEAR_FAR_MODE
 920                                    | CullSettings::CULLING_MODE
 921 #if defined(HAVE_CULLSETTINGS_CLEAR_MASK)
 922                                    | CullSettings::CLEAR_MASK
 923 #endif
 924                                    ));
 925     camera->setComputeNearFarMode(osg::CullSettings::DO_NOT_COMPUTE_NEAR_FAR);
 926     camera->setCullingMode(osg::CullSettings::NO_CULLING);
 927     camera->setProjectionResizePolicy(Camera::FIXED);
 928     camera->setReferenceFrame(Transform::ABSOLUTE_RF);
 929     const int cameraFlags = GUI | DO_INTERSECTION_TEST;
 930     CameraInfo* result = addCamera(cameraFlags, camera, Matrixd::identity(),
 931                                    Matrixd::identity(), false);
 932     SGPropertyNode* viewportNode = cameraNode->getNode("viewport", true);
 933     buildViewport(result, viewportNode, window->gc->getTraits());
 934
 935     // Disable statistics for the GUI camera.
 936     result->camera->setStats(0);
 937     updateCameras(result);
 938     return result;
 939 }
 940
 941 CameraGroup* CameraGroup::buildCameraGroup(osgViewer::Viewer* viewer,
 942                                            SGPropertyNode* gnode)
 943 {
 944     CameraGroup* cgroup = new CameraGroup(viewer);
 945     for (int i = 0; i < gnode->nChildren(); ++i) {
 946         SGPropertyNode* pNode = gnode->getChild(i);
 947         const char* name = pNode->getName();
 948         if (!strcmp(name, "camera")) {
 949             cgroup->buildCamera(pNode);
 950         } else if (!strcmp(name, "window")) {
 951             WindowBuilder::getWindowBuilder()->buildWindow(pNode);
 952         } else if (!strcmp(name, "gui")) {
 953             cgroup->buildGUICamera(pNode);
 954         }
 955     }
 956     bindMemberToNode(gnode, "znear", cgroup, &CameraGroup::_zNear, .1f);
 957     bindMemberToNode(gnode, "zfar", cgroup, &CameraGroup::_zFar, 120000.0f);
 958     bindMemberToNode(gnode, "near-field", cgroup, &CameraGroup::_nearField,
 959                      100.0f);
 960     return cgroup;
 961 }
 962
 963 void CameraGroup::setCameraCullMasks(Node::NodeMask nm)
 964 {
 965     for (CameraIterator i = camerasBegin(), e = camerasEnd(); i != e; ++i) {
 966         CameraInfo* info = i->get();
 967         if (info->flags & GUI)
 968             continue;
 969         if (info->farCamera.valid() && info->farCamera->getNodeMask() != 0) {
 970             info->camera->setCullMask(nm & ~simgear::BACKGROUND_BIT);
 971             info->camera->setCullMaskLeft(nm & ~simgear::BACKGROUND_BIT);
 972             info->camera->setCullMaskRight(nm & ~simgear::BACKGROUND_BIT);
 973             info->farCamera->setCullMask(nm);
 974             info->farCamera->setCullMaskLeft(nm);
 975             info->farCamera->setCullMaskRight(nm);
 976         } else {
 977             info->camera->setCullMask(nm);
 978             info->camera->setCullMaskLeft(nm);
 979             info->camera->setCullMaskRight(nm);
 980         }
 981     }
 982 }
 983
 984 void CameraGroup::resized()
 985 {
 986     for (CameraIterator i = camerasBegin(), e = camerasEnd(); i != e; ++i) {
 987         CameraInfo *info = i->get();
 988         const Viewport* viewport = info->camera->getViewport();
 989         info->x = viewport->x();
 990         info->y = viewport->y();
 991         info->width = viewport->width();
 992         info->height = viewport->height();
 993     }
 994 }
 995
 996 const CameraInfo* CameraGroup::getGUICamera() const
 997 {
 998     ConstCameraIterator result
 999         = std::find_if(camerasBegin(), camerasEnd(),
1000                    FlagTester<CameraInfo>(GUI));
1001     if (result == camerasEnd()) {
1002         return NULL;
1003     }
1004
1005     return *result;
1006 }
1007
1008 Camera* getGUICamera(CameraGroup* cgroup)
1009 {
1010     const CameraInfo* info = cgroup->getGUICamera();
1011     if (!info) {
1012         return NULL;
1013     }
1014
1015     return info->camera.get();
1016 }
1017
1018 static bool computeCameraIntersection(const CameraInfo* cinfo,
1019                                       const osgGA::GUIEventAdapter* ea,
1020                                       osgUtil::LineSegmentIntersector::Intersections& intersections)
1021 {
1022   using osgUtil::Intersector;
1023   using osgUtil::LineSegmentIntersector;
1024   double x, y;
1025   eventToWindowCoords(ea, x, y);
1026
1027   if (!(cinfo->flags & CameraGroup::DO_INTERSECTION_TEST))
1028     return false;
1029
1030   const Camera* camera = cinfo->camera.get();
1031   if (camera->getGraphicsContext() != ea->getGraphicsContext())
1032     return false;
1033
1034   const Viewport* viewport = camera->getViewport();
1035   double epsilon = 0.5;
1036   if (!(x >= viewport->x() - epsilon
1037         && x < viewport->x() + viewport->width() -1.0 + epsilon
1038         && y >= viewport->y() - epsilon
1039         && y < viewport->y() + viewport->height() -1.0 + epsilon))
1040     return false;
1041
1042   Vec4d start(x, y, 0.0, 1.0);
1043   Vec4d end(x, y, 1.0, 1.0);
1044   Matrix windowMat = viewport->computeWindowMatrix();
1045   Matrix startPtMat = Matrix::inverse(camera->getProjectionMatrix()
1046                                       * windowMat);
1047   Matrix endPtMat;
1048   if (!cinfo->farCamera.valid() || cinfo->farCamera->getNodeMask() == 0)
1049     endPtMat = startPtMat;
1050   else
1051     endPtMat = Matrix::inverse(cinfo->farCamera->getProjectionMatrix()
1052                                * windowMat);
1053   start = start * startPtMat;
1054   start /= start.w();
1055   end = end * endPtMat;
1056   end /= end.w();
1057   ref_ptr<LineSegmentIntersector> picker
1058   = new LineSegmentIntersector(Intersector::VIEW,
1059                                Vec3d(start.x(), start.y(), start.z()),
1060                                Vec3d(end.x(), end.y(), end.z()));
1061   osgUtil::IntersectionVisitor iv(picker.get());
1062   const_cast<Camera*>(camera)->accept(iv);
1063   if (picker->containsIntersections()) {
1064     intersections = picker->getIntersections();
1065     return true;
1066   }
1067
1068   return false;
1069 }
1070
1071 bool computeIntersections(const CameraGroup* cgroup,
1072                           const osgGA::GUIEventAdapter* ea,
1073                           osgUtil::LineSegmentIntersector::Intersections& intersections)
1074 {
1075     // test the GUI first
1076     const CameraInfo* guiCamera = cgroup->getGUICamera();
1077     if (guiCamera && computeCameraIntersection(guiCamera, ea, intersections))
1078         return true;
1079
1080     // Find camera that contains event
1081     for (CameraGroup::ConstCameraIterator iter = cgroup->camerasBegin(),
1082              e = cgroup->camerasEnd();
1083          iter != e;
1084          ++iter) {
1085         const CameraInfo* cinfo = iter->get();
1086         if (cinfo == guiCamera)
1087             continue;
1088
1089         if (computeCameraIntersection(cinfo, ea, intersections))
1090             return true;
1091     }
1092
1093     intersections.clear();
1094     return false;
1095 }
1096
1097 void warpGUIPointer(CameraGroup* cgroup, int x, int y)
1098 {
1099     using osgViewer::GraphicsWindow;
1100     Camera* guiCamera = getGUICamera(cgroup);
1101     if (!guiCamera)
1102         return;
1103     Viewport* vport = guiCamera->getViewport();
1104     GraphicsWindow* gw
1105         = dynamic_cast<GraphicsWindow*>(guiCamera->getGraphicsContext());
1106     if (!gw)
1107         return;
1108     globals->get_renderer()->getEventHandler()->setMouseWarped();
1109     // Translate the warp request into the viewport of the GUI camera,
1110     // send the request to the window, then transform the coordinates
1111     // for the Viewer's event queue.
1112     double wx = x + vport->x();
1113     double wyUp = vport->height() + vport->y() - y;
1114     double wy;
1115     const GraphicsContext::Traits* traits = gw->getTraits();
1116     if (gw->getEventQueue()->getCurrentEventState()->getMouseYOrientation()
1117         == osgGA::GUIEventAdapter::Y_INCREASING_DOWNWARDS) {
1118         wy = traits->height - wyUp;
1119     } else {
1120         wy = wyUp;
1121     }
1122     gw->getEventQueue()->mouseWarped(wx, wy);
1123     gw->requestWarpPointer(wx, wy);
1124     osgGA::GUIEventAdapter* eventState
1125         = cgroup->getViewer()->getEventQueue()->getCurrentEventState();
1126     double viewerX
1127         = (eventState->getXmin()
1128            + ((wx / double(traits->width))
1129               * (eventState->getXmax() - eventState->getXmin())));
1130     double viewerY
1131         = (eventState->getYmin()
1132            + ((wyUp / double(traits->height))
1133               * (eventState->getYmax() - eventState->getYmin())));
1134     cgroup->getViewer()->getEventQueue()->mouseWarped(viewerX, viewerY);
1135 }
1136 }