672 lines
19 KiB
C++
672 lines
19 KiB
C++
#include <osgGA/TerrainManipulator>
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#include <osg/Quat>
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#include <osg/Notify>
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#include <osgUtil/IntersectVisitor>
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using namespace osg;
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using namespace osgGA;
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TerrainManipulator::TerrainManipulator()
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{
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_rotationMode =ELEVATION_AZIM;
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_distance = 1.0;
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_thrown = false;
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}
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TerrainManipulator::~TerrainManipulator()
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{
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}
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void TerrainManipulator::setRotationMode(RotationMode mode)
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{
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_rotationMode = mode;
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// need to correct rotation.
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}
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void TerrainManipulator::setNode(osg::Node* node)
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{
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_node = node;
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if (_node.get())
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{
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const osg::BoundingSphere& boundingSphere=_node->getBound();
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const float minimumDistanceScale = 0.001f;
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_minimumDistance = osg::clampBetween(
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boundingSphere._radius * minimumDistanceScale,
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0.00001f,1.0f);
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osg::notify(osg::INFO)<<"Setting terrain manipulator _minimumDistance to "<<_minimumDistance<<std::endl;
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}
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if (getAutoComputeHomePosition()) computeHomePosition();
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}
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const osg::Node* TerrainManipulator::getNode() const
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{
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return _node.get();
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}
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osg::Node* TerrainManipulator::getNode()
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{
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return _node.get();
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}
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void TerrainManipulator::home(const GUIEventAdapter& ,GUIActionAdapter& us)
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{
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if (getAutoComputeHomePosition()) computeHomePosition();
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computePosition(_homeEye, _homeCenter, _homeUp);
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us.requestRedraw();
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}
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void TerrainManipulator::init(const GUIEventAdapter& ,GUIActionAdapter& )
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{
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flushMouseEventStack();
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}
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void TerrainManipulator::getUsage(osg::ApplicationUsage& usage) const
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{
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usage.addKeyboardMouseBinding("Trackball: Space","Reset the viewing position to home");
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usage.addKeyboardMouseBinding("Trackball: +","When in stereo, increase the fusion distance");
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usage.addKeyboardMouseBinding("Trackball: -","When in stereo, reduse the fusion distance");
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}
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bool TerrainManipulator::handle(const GUIEventAdapter& ea,GUIActionAdapter& us)
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{
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switch(ea.getEventType())
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{
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case(GUIEventAdapter::PUSH):
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{
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flushMouseEventStack();
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addMouseEvent(ea);
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if (calcMovement()) us.requestRedraw();
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us.requestContinuousUpdate(false);
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_thrown = false;
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return true;
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}
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case(GUIEventAdapter::RELEASE):
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{
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if (ea.getButtonMask()==0)
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{
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if (isMouseMoving())
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{
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if (calcMovement())
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{
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us.requestRedraw();
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us.requestContinuousUpdate(true);
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_thrown = true;
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}
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}
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else
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{
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flushMouseEventStack();
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addMouseEvent(ea);
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if (calcMovement()) us.requestRedraw();
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us.requestContinuousUpdate(false);
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_thrown = false;
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}
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}
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else
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{
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flushMouseEventStack();
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addMouseEvent(ea);
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if (calcMovement()) us.requestRedraw();
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us.requestContinuousUpdate(false);
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_thrown = false;
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}
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return true;
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}
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case(GUIEventAdapter::DRAG):
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{
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addMouseEvent(ea);
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if (calcMovement()) us.requestRedraw();
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us.requestContinuousUpdate(false);
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_thrown = false;
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return true;
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}
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case(GUIEventAdapter::MOVE):
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{
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return false;
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}
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case(GUIEventAdapter::KEYDOWN):
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if (ea.getKey()==' ')
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{
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flushMouseEventStack();
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_thrown = false;
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home(ea,us);
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us.requestRedraw();
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us.requestContinuousUpdate(false);
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return true;
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}
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return false;
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case(GUIEventAdapter::FRAME):
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if (_thrown)
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{
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if (calcMovement()) us.requestRedraw();
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}
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return false;
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default:
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return false;
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}
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}
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bool TerrainManipulator::isMouseMoving()
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{
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if (_ga_t0.get()==NULL || _ga_t1.get()==NULL) return false;
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static const float velocity = 0.1f;
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float dx = _ga_t0->getXnormalized()-_ga_t1->getXnormalized();
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float dy = _ga_t0->getYnormalized()-_ga_t1->getYnormalized();
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float len = sqrtf(dx*dx+dy*dy);
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float dt = _ga_t0->time()-_ga_t1->time();
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return (len>dt*velocity);
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}
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void TerrainManipulator::flushMouseEventStack()
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{
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_ga_t1 = NULL;
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_ga_t0 = NULL;
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}
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void TerrainManipulator::addMouseEvent(const GUIEventAdapter& ea)
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{
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_ga_t1 = _ga_t0;
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_ga_t0 = &ea;
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}
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void TerrainManipulator::setByMatrix(const osg::Matrixd& matrix)
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{
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osg::Vec3 lookVector(- matrix(2,0),-matrix(2,1),-matrix(2,2));
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osg::Vec3 eye(matrix(3,0),matrix(3,1),matrix(3,2));
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osg::notify(INFO)<<"eye point "<<eye<<std::endl;
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osg::notify(INFO)<<"lookVector "<<lookVector<<std::endl;
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if (!_node)
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{
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_center = eye+ lookVector;
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_distance = lookVector.length();
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matrix.get(_rotation);
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return;
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}
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// need to reintersect with the terrain
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osgUtil::IntersectVisitor iv;
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const osg::BoundingSphere& bs = _node->getBound();
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float distance = (eye-bs.center()).length() + _node->getBound().radius();
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osg::Vec3d start_segment = eye;
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osg::Vec3d end_segment = eye + lookVector*distance;
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//CoordinateFrame coordinateFrame = getCoordinateFrame(_center.x(), _center.y(), _center.z());
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//osg::notify(INFO)<<"start="<<start_segment<<"\tend="<<end_segment<<"\tupVector="<<getUpVector(coordinateFrame)<<std::endl;
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osg::ref_ptr<osg::LineSegment> segLookVector = new osg::LineSegment;
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segLookVector->set(start_segment,end_segment);
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iv.addLineSegment(segLookVector.get());
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_node->accept(iv);
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bool hitFound = false;
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if (iv.hits())
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{
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osgUtil::IntersectVisitor::HitList& hitList = iv.getHitList(segLookVector.get());
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if (!hitList.empty())
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{
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notify(INFO) << "Hit terrain ok A"<< std::endl;
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osg::Vec3d ip = hitList.front().getWorldIntersectPoint();
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_center = ip;
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_distance = (eye-ip).length();
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osg::Matrix rotation_matrix = osg::Matrixd::translate(0.0,0.0,-_distance)*
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matrix*
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osg::Matrixd::translate(-_center);
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rotation_matrix.get(_rotation);
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hitFound = true;
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}
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}
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if (!hitFound)
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{
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CoordinateFrame eyePointCoordFrame = getCoordinateFrame( eye );
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// clear the intersect visitor ready for a new test
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iv.reset();
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osg::ref_ptr<osg::LineSegment> segDowVector = new osg::LineSegment;
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segLookVector->set(eye+getUpVector(eyePointCoordFrame)*distance,
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eye-getUpVector(eyePointCoordFrame)*distance);
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iv.addLineSegment(segLookVector.get());
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_node->accept(iv);
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hitFound = false;
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if (iv.hits())
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{
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osgUtil::IntersectVisitor::HitList& hitList = iv.getHitList(segLookVector.get());
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if (!hitList.empty())
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{
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notify(INFO) << "Hit terrain ok B"<< std::endl;
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osg::Vec3d ip = hitList.front().getWorldIntersectPoint();
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_center = ip;
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_distance = (eye-ip).length();
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_rotation.set(0,0,0,1);
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hitFound = true;
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}
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}
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}
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CoordinateFrame coordinateFrame = getCoordinateFrame(_center);
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_previousUp = getUpVector(coordinateFrame);
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clampOrientation();
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}
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osg::Matrixd TerrainManipulator::getMatrix() const
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{
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return osg::Matrixd::translate(0.0,0.0,_distance)*osg::Matrixd::rotate(_rotation)*osg::Matrix::translate(_center);
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}
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osg::Matrixd TerrainManipulator::getInverseMatrix() const
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{
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return osg::Matrix::translate(-_center)*osg::Matrixd::rotate(_rotation.inverse())*osg::Matrixd::translate(0.0,0.0,-_distance);
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}
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void TerrainManipulator::computePosition(const osg::Vec3d& eye,const osg::Vec3d& center,const osg::Vec3d& up)
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{
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if (!_node) return;
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// compute rotation matrix
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osg::Vec3 lv(center-eye);
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_distance = lv.length();
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_center = center;
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if (_node.valid())
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{
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// compute the itersection with the scene.
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osgUtil::IntersectVisitor iv;
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osg::ref_ptr<osg::LineSegment> segLookVector = new osg::LineSegment;
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segLookVector->set(eye,center);
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iv.addLineSegment(segLookVector.get());
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_node->accept(iv);
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bool hitFound = false;
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if (iv.hits())
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{
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osgUtil::IntersectVisitor::HitList& hitList = iv.getHitList(segLookVector.get());
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if (!hitList.empty())
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{
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osg::notify(osg::INFO) << "Hit terrain ok C"<< std::endl;
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osg::Vec3d ip = hitList.front().getWorldIntersectPoint();
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_center = ip;
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_distance = (ip-eye).length();
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hitFound = true;
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}
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}
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}
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// note LookAt = inv(CF)*inv(RM)*inv(T) which is equivilant to:
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// inv(R) = CF*LookAt.
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osg::Matrixd rotation_matrix = osg::Matrixd::lookAt(eye,center,up);
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rotation_matrix.get(_rotation);
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_rotation = _rotation.inverse();
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CoordinateFrame coordinateFrame = getCoordinateFrame(_center);
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_previousUp = getUpVector(coordinateFrame);
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clampOrientation();
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}
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bool TerrainManipulator::calcMovement()
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{
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// return if less then two events have been added.
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if (_ga_t0.get()==NULL || _ga_t1.get()==NULL) return false;
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double dx = _ga_t0->getXnormalized()-_ga_t1->getXnormalized();
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double dy = _ga_t0->getYnormalized()-_ga_t1->getYnormalized();
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// return if there is no movement.
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if (dx==0 && dy==0) return false;
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unsigned int buttonMask = _ga_t1->getButtonMask();
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if (buttonMask==GUIEventAdapter::LEFT_MOUSE_BUTTON)
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{
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if (_rotationMode==ELEVATION_AZIM_ROLL)
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{
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// rotate camera.
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osg::Vec3 axis;
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double angle;
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double px0 = _ga_t0->getXnormalized();
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double py0 = _ga_t0->getYnormalized();
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double px1 = _ga_t1->getXnormalized();
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double py1 = _ga_t1->getYnormalized();
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trackball(axis,angle,px1,py1,px0,py0);
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osg::Quat new_rotate;
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new_rotate.makeRotate(angle,axis);
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_rotation = _rotation*new_rotate;
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}
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else
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{
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osg::Matrix rotation_matrix;
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rotation_matrix.set(_rotation);
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osg::Vec3d lookVector = -getUpVector(rotation_matrix);
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osg::Vec3d sideVector = getSideVector(rotation_matrix);
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osg::Vec3d upVector = getFrontVector(rotation_matrix);
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CoordinateFrame coordinateFrame = getCoordinateFrame(_center);
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osg::Vec3d localUp = getUpVector(coordinateFrame);
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//osg::Vec3d localUp = _previousUp;
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osg::Vec3d forwardVector = localUp^sideVector;
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sideVector = forwardVector^localUp;
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forwardVector.normalize();
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sideVector.normalize();
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osg::Quat rotate_elevation;
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rotate_elevation.makeRotate(dy,sideVector);
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osg::Quat rotate_azim;
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rotate_azim.makeRotate(-dx,localUp);
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_rotation = _rotation * rotate_elevation * rotate_azim;
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}
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return true;
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}
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else if (buttonMask==GUIEventAdapter::MIDDLE_MOUSE_BUTTON ||
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buttonMask==(GUIEventAdapter::LEFT_MOUSE_BUTTON|GUIEventAdapter::RIGHT_MOUSE_BUTTON))
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{
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// pan model.
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double scale = -0.3f*_distance;
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osg::Matrix rotation_matrix;
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rotation_matrix.set(_rotation);
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// compute look vector.
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osg::Vec3d lookVector = -getUpVector(rotation_matrix);
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osg::Vec3d sideVector = getSideVector(rotation_matrix);
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osg::Vec3d upVector = getFrontVector(rotation_matrix);
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// CoordinateFrame coordinateFrame = getCoordinateFrame(_center);
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// osg::Vec3d localUp = getUpVector(coordinateFrame);
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osg::Vec3d localUp = _previousUp;
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osg::Vec3d forwardVector =localUp^sideVector;
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sideVector = forwardVector^localUp;
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forwardVector.normalize();
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sideVector.normalize();
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osg::Vec3d dv = forwardVector * (dy*scale) + sideVector * (dx*scale);
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_center += dv;
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// need to recompute the itersection point along the look vector.
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if (_node.valid())
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{
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// now reorientate the coordinate frame to the frame coords.
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CoordinateFrame coordinateFrame = getCoordinateFrame(_center);
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// need to reintersect with the terrain
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osgUtil::IntersectVisitor iv;
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double distance = _node->getBound().radius()*0.1f;
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osg::Vec3d start_segment = _center + getUpVector(coordinateFrame) * distance;
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osg::Vec3d end_segment = start_segment - getUpVector(coordinateFrame) * (2.0f*distance);
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osg::notify(INFO)<<"start="<<start_segment<<"\tend="<<end_segment<<"\tupVector="<<getUpVector(coordinateFrame)<<std::endl;
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osg::ref_ptr<osg::LineSegment> segLookVector = new osg::LineSegment;
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segLookVector->set(start_segment,end_segment);
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iv.addLineSegment(segLookVector.get());
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_node->accept(iv);
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bool hitFound = false;
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if (iv.hits())
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{
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osgUtil::IntersectVisitor::HitList& hitList = iv.getHitList(segLookVector.get());
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if (!hitList.empty())
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{
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notify(INFO) << "Hit terrain ok"<< std::endl;
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osg::Vec3d ip = hitList.front().getWorldIntersectPoint();
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_center = ip;
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hitFound = true;
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}
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}
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if (!hitFound)
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{
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// ??
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osg::notify(INFO)<<"TerrainManipulator unable to intersect with terrain."<<std::endl;
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}
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coordinateFrame = getCoordinateFrame(_center);
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osg::Vec3d new_localUp = getUpVector(coordinateFrame);
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osg::Quat pan_rotation;
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pan_rotation.makeRotate(localUp,new_localUp);
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if (!pan_rotation.zeroRotation())
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{
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_rotation = _rotation * pan_rotation;
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_previousUp = new_localUp;
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//osg::notify(osg::NOTICE)<<"Rotating from "<<localUp<<" to "<<new_localUp<<" angle = "<<acos(localUp*new_localUp/(localUp.length()*new_localUp.length()))<<std::endl;
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//clampOrientation();
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}
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else
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{
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osg::notify(osg::INFO)<<"New up orientation nearly inline - no need to rotate"<<std::endl;
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}
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}
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return true;
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}
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else if (buttonMask==GUIEventAdapter::RIGHT_MOUSE_BUTTON)
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{
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// zoom model.
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double fd = _distance;
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double scale = 1.0f+dy;
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if (fd*scale>_minimumDistance)
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{
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_distance *= scale;
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} else
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{
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_distance = _minimumDistance;
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}
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return true;
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}
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return false;
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}
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void TerrainManipulator::clampOrientation()
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{
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if (_rotationMode==ELEVATION_AZIM)
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{
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osg::Matrix rotation_matrix;
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rotation_matrix.set(_rotation);
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osg::Vec3d lookVector = -getUpVector(rotation_matrix);
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osg::Vec3d upVector = getFrontVector(rotation_matrix);
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CoordinateFrame coordinateFrame = getCoordinateFrame(_center);
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osg::Vec3d localUp = getUpVector(coordinateFrame);
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//osg::Vec3d localUp = _previousUp;
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osg::Vec3d sideVector = lookVector ^ localUp;
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if (sideVector.length()<0.1)
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{
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osg::notify(osg::INFO)<<"Side vector short "<<sideVector.length()<<std::endl;
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sideVector = upVector^localUp;
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|
sideVector.normalize();
|
|
|
|
}
|
|
|
|
Vec3d newUpVector = sideVector^lookVector;
|
|
newUpVector.normalize();
|
|
|
|
osg::Quat rotate_roll;
|
|
rotate_roll.makeRotate(upVector,newUpVector);
|
|
|
|
if (!rotate_roll.zeroRotation())
|
|
{
|
|
_rotation = _rotation * rotate_roll;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* This size should really be based on the distance from the center of
|
|
* rotation to the point on the object underneath the mouse. That
|
|
* point would then track the mouse as closely as possible. This is a
|
|
* simple example, though, so that is left as an Exercise for the
|
|
* Programmer.
|
|
*/
|
|
const float TRACKBALLSIZE = 0.8f;
|
|
|
|
/*
|
|
* Ok, simulate a track-ball. Project the points onto the virtual
|
|
* trackball, then figure out the axis of rotation, which is the cross
|
|
* product of P1 P2 and O P1 (O is the center of the ball, 0,0,0)
|
|
* Note: This is a deformed trackball-- is a trackball in the center,
|
|
* but is deformed into a hyperbolic sheet of rotation away from the
|
|
* center. This particular function was chosen after trying out
|
|
* several variations.
|
|
*
|
|
* It is assumed that the arguments to this routine are in the range
|
|
* (-1.0 ... 1.0)
|
|
*/
|
|
void TerrainManipulator::trackball(osg::Vec3& axis,double & angle, double p1x, double p1y, double p2x, double p2y)
|
|
{
|
|
/*
|
|
* First, figure out z-coordinates for projection of P1 and P2 to
|
|
* deformed sphere
|
|
*/
|
|
|
|
osg::Matrix rotation_matrix(_rotation);
|
|
|
|
|
|
osg::Vec3d uv = osg::Vec3d(0.0,1.0,0.0)*rotation_matrix;
|
|
osg::Vec3d sv = osg::Vec3d(1.0,0.0,0.0)*rotation_matrix;
|
|
osg::Vec3d lv = osg::Vec3d(0.0,0.0,-1.0)*rotation_matrix;
|
|
|
|
osg::Vec3d p1 = sv*p1x+uv*p1y-lv*tb_project_to_sphere(TRACKBALLSIZE,p1x,p1y);
|
|
osg::Vec3d p2 = sv*p2x+uv*p2y-lv*tb_project_to_sphere(TRACKBALLSIZE,p2x,p2y);
|
|
|
|
/*
|
|
* Now, we want the cross product of P1 and P2
|
|
*/
|
|
|
|
// Robert,
|
|
//
|
|
// This was the quick 'n' dirty fix to get the trackball doing the right
|
|
// thing after fixing the Quat rotations to be right-handed. You may want
|
|
// to do something more elegant.
|
|
// axis = p1^p2;
|
|
axis = p2^p1;
|
|
axis.normalize();
|
|
|
|
/*
|
|
* Figure out how much to rotate around that axis.
|
|
*/
|
|
double t = (p2-p1).length() / (2.0*TRACKBALLSIZE);
|
|
|
|
/*
|
|
* Avoid problems with out-of-control values...
|
|
*/
|
|
if (t > 1.0) t = 1.0;
|
|
if (t < -1.0) t = -1.0;
|
|
angle = inRadians(asin(t));
|
|
|
|
}
|
|
|
|
|
|
/*
|
|
* Project an x,y pair onto a sphere of radius r OR a hyperbolic sheet
|
|
* if we are away from the center of the sphere.
|
|
*/
|
|
double TerrainManipulator::tb_project_to_sphere(double r, double x, double y)
|
|
{
|
|
float d, t, z;
|
|
|
|
d = sqrt(x*x + y*y);
|
|
/* Inside sphere */
|
|
if (d < r * 0.70710678118654752440)
|
|
{
|
|
z = sqrt(r*r - d*d);
|
|
} /* On hyperbola */
|
|
else
|
|
{
|
|
t = r / 1.41421356237309504880;
|
|
z = t*t / d;
|
|
}
|
|
return z;
|
|
}
|