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