OpenSceneGraph/src/osgUtil/TrackballManipulator.cpp
Robert Osfield 6da953e31d Moved the setting of camera fusion distance mode into the handle method so that
it is updated on everyframe to ensure that switching between Drive/Flight
and Trackball happens seemlessly.
2002-01-05 16:18:46 +00:00

392 lines
10 KiB
C++

#include <osgUtil/TrackballManipulator>
#include <osg/Types>
#include <osg/Notify>
using namespace osg;
using namespace osgUtil;
TrackballManipulator::TrackballManipulator()
{
_modelScale = 0.01f;
_minimumZoomScale = 0.05f;
_thrown = false;
}
TrackballManipulator::~TrackballManipulator()
{
}
void TrackballManipulator::setNode(osg::Node* node)
{
_node = node;
if (_node.get())
{
const osg::BoundingSphere& boundingSphere=_node->getBound();
_modelScale = boundingSphere._radius;
}
}
const osg::Node* TrackballManipulator::getNode() const
{
return _node.get();
}
/*ea*/
void TrackballManipulator::home(const GUIEventAdapter& ,GUIActionAdapter& us)
{
if(_node.get() && _camera.get())
{
const osg::BoundingSphere& boundingSphere=_node->getBound();
_camera->setView(boundingSphere._center+osg::Vec3( 0.0,-3.0f * boundingSphere._radius,0.0f),
boundingSphere._center,
osg::Vec3(0.0f,0.0f,1.0f));
us.requestRedraw();
}
}
void TrackballManipulator::init(const GUIEventAdapter& ,GUIActionAdapter& )
{
flushMouseEventStack();
}
bool TrackballManipulator::handle(const GUIEventAdapter& ea,GUIActionAdapter& us)
{
if(!_camera.get()) return false;
switch(ea.getEventType())
{
case(GUIEventAdapter::PUSH):
{
flushMouseEventStack();
addMouseEvent(ea);
if (calcMovement()) us.requestRedraw();
us.requestContinuousUpdate(false);
_thrown = false;
return true;
}
case(GUIEventAdapter::RELEASE):
{
if (ea.getButtonMask()==0)
{
if (isMouseMoving())
{
if (calcMovement())
{
us.requestRedraw();
us.requestContinuousUpdate(true);
_thrown = true;
}
}
else
{
flushMouseEventStack();
addMouseEvent(ea);
if (calcMovement()) us.requestRedraw();
us.requestContinuousUpdate(false);
_thrown = false;
}
}
else
{
flushMouseEventStack();
addMouseEvent(ea);
if (calcMovement()) us.requestRedraw();
us.requestContinuousUpdate(false);
_thrown = false;
}
return true;
}
case(GUIEventAdapter::DRAG):
{
addMouseEvent(ea);
if (calcMovement()) us.requestRedraw();
us.requestContinuousUpdate(false);
_thrown = false;
return true;
}
case(GUIEventAdapter::MOVE):
{
return false;
}
case(GUIEventAdapter::KEYBOARD):
if (ea.getKey()==' ')
{
flushMouseEventStack();
_thrown = false;
home(ea,us);
us.requestRedraw();
us.requestContinuousUpdate(false);
return true;
} else if (ea.getKey()=='+')
{
_camera->setFusionDistanceRatio(_camera->getFusionDistanceRatio()*1.25f);
return true;
}
else if (ea.getKey()=='-')
{
_camera->setFusionDistanceRatio(_camera->getFusionDistanceRatio()/1.25f);
return true;
}
return false;
case(GUIEventAdapter::FRAME):
_camera->setFusionDistanceMode(osg::Camera::PROPORTIONAL_TO_LOOK_DISTANCE);
if (_thrown)
{
if (calcMovement()) us.requestRedraw();
return true;
}
return false;
default:
return false;
}
}
bool TrackballManipulator::isMouseMoving()
{
if (_ga_t0.get()==NULL || _ga_t1.get()==NULL) return false;
static const float velocity = 100.0f;
float dx = _ga_t0->getX()-_ga_t1->getX();
float dy = _ga_t0->getY()-_ga_t1->getY();
float len = sqrtf(dx*dx+dy*dy);
float dt = _ga_t0->time()-_ga_t1->time();
return (len>dt*velocity);
}
void TrackballManipulator::flushMouseEventStack()
{
_ga_t1 = NULL;
_ga_t0 = NULL;
}
void TrackballManipulator::addMouseEvent(const GUIEventAdapter& ea)
{
_ga_t1 = _ga_t0;
_ga_t0 = &ea;
}
bool TrackballManipulator::calcMovement()
{
// return if less then two events have been added.
if (_ga_t0.get()==NULL || _ga_t1.get()==NULL) return false;
float dx = _ga_t0->getX()-_ga_t1->getX();
float dy = _ga_t0->getY()-_ga_t1->getY();
// return if there is no movement.
if (dx==0 && dy==0) return false;
float focalLength = (_camera->getCenterPoint()-_camera->getEyePoint()).length();
unsigned int buttonMask = _ga_t1->getButtonMask();
if (buttonMask==GUIEventAdapter::LEFT_BUTTON)
{
// rotate camera.
osg::Vec3 center = _camera->getCenterPoint();
osg::Vec3 axis;
float angle;
float mx0 = (_ga_t0->getXmin()+_ga_t0->getXmax())/2.0f;
float rx0 = (_ga_t0->getXmax()-_ga_t0->getXmin())/2.0f;
float my0 = (_ga_t0->getYmin()+_ga_t0->getYmax())/2.0f;
float ry0 = (_ga_t0->getYmax()-_ga_t0->getYmin())/2.0f;
float mx1 = (_ga_t0->getXmin()+_ga_t1->getXmax())/2.0f;
float rx1 = (_ga_t0->getXmax()-_ga_t1->getXmin())/2.0f;
float my1 = (_ga_t1->getYmin()+_ga_t1->getYmax())/2.0f;
float ry1 = (_ga_t1->getYmax()-_ga_t1->getYmin())/2.0f;
float px0 = (_ga_t0->getX()-mx0)/rx0;
float py0 = (my0-_ga_t0->getY())/ry0;
float px1 = (_ga_t1->getX()-mx1)/rx1;
float py1 = (my1-_ga_t1->getY())/ry1;
trackball(axis,angle,px1,py1,px0,py0);
osg::Matrix mat;
mat.makeTranslate(-center.x(),-center.y(),-center.z());
mat *= Matrix::rotate(angle,axis.x(),axis.y(),axis.z());
mat *= Matrix::translate(center.x(),center.y(),center.z());
_camera->transformLookAt(mat);
return true;
}
else if (buttonMask==GUIEventAdapter::MIDDLE_BUTTON ||
buttonMask==(GUIEventAdapter::LEFT_BUTTON|GUIEventAdapter::RIGHT_BUTTON))
{
// pan model.
float scale = 0.0015f*focalLength;
osg::Vec3 uv = _camera->getUpVector();
osg::Vec3 sv = _camera->getSideVector();
osg::Vec3 dv = uv*(dy*scale)-sv*(dx*scale);
osg::Matrix mat;
mat.makeTranslate(dv.x(),dv.y(),dv.z());
_camera->transformLookAt(mat);
return true;
}
else if (buttonMask==GUIEventAdapter::RIGHT_BUTTON)
{
// zoom model.
float fd = focalLength;
float scale = 1.0f-dy*0.001f;
if (fd*scale>_modelScale*_minimumZoomScale)
{
// zoom camera in.
osg::Vec3 center = _camera->getCenterPoint();
osg::Matrix mat;
mat.makeTranslate(-center.x(),-center.y(),-center.z());
mat *= Matrix::scale(scale,scale,scale);
mat *= Matrix::translate(center.x(),center.y(),center.z());
_camera->transformLookAt(mat);
}
else
{
// notify(DEBUG_INFO) << "Pushing forward"<<std::endl;
// push the camera forward.
float scale = 0.0015f*fd;
osg::Vec3 dv = _camera->getLookVector()*(dy*scale);
osg::Matrix mat;
mat.makeTranslate(dv.x(),dv.y(),dv.z());
_camera->transformLookAt(mat);
}
return true;
}
return false;
}
/*
* 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 TrackballManipulator::trackball(osg::Vec3& axis,float& angle, float p1x, float p1y, float p2x, float p2y)
{
/*
* First, figure out z-coordinates for projection of P1 and P2 to
* deformed sphere
*/
osg::Vec3 uv = _camera->getUpVector();
osg::Vec3 sv = _camera->getSideVector();
osg::Vec3 lv = _camera->getLookVector();
osg::Vec3 p1 = sv*p1x+uv*p1y-lv*tb_project_to_sphere(TRACKBALLSIZE,p1x,p1y);
osg::Vec3 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.
*/
float 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.
*/
float TrackballManipulator::tb_project_to_sphere(float r, float x, float 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;
}