Files
OpenSceneGraph/src/osgUtil/TransformCallback.cpp
2012-03-21 17:36:20 +00:00

68 lines
2.2 KiB
C++

/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* OpenSceneGraph Public License for more details.
*/
#include <osg/MatrixTransform>
#include <osgUtil/TransformCallback>
using namespace osgUtil;
TransformCallback::TransformCallback(const osg::Vec3& pivot,const osg::Vec3& axis,float angularVelocity)
{
_pivot = pivot;
_axis = axis;
_angular_velocity = angularVelocity;
_previousTraversalNumber = osg::UNINITIALIZED_FRAME_NUMBER;
_previousTime = -1.0;
_pause = false;
}
void TransformCallback::operator() (osg::Node* node, osg::NodeVisitor* nv)
{
osg::MatrixTransform* transform = dynamic_cast<osg::MatrixTransform*>(node);
if (nv && transform)
{
const osg::FrameStamp* fs = nv->getFrameStamp();
if (!fs) return; // not frame stamp, no handle on the time so can't move.
double newTime = fs->getSimulationTime();
// ensure that we do not operate on this node more than
// once during this traversal. This is an issue since node
// can be shared between multiple parents.
if (!_pause && nv->getTraversalNumber()!=_previousTraversalNumber)
{
float delta_angle = _angular_velocity*(newTime-_previousTime);
osg::Matrix mat = osg::Matrix::translate(-_pivot)*
osg::Matrix::rotate(delta_angle,_axis)*
osg::Matrix::translate(_pivot);
// update the specified transform
transform->preMult(mat);
_previousTraversalNumber = nv->getTraversalNumber();
}
_previousTime = newTime;
}
// must call any nested node callbacks and continue subgraph traversal.
traverse(node,nv);
}