OpenSceneGraph/include/osgParticle/ForceOperator

99 lines
3.0 KiB
C++

/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 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.
*/
//osgParticle - Copyright (C) 2002 Marco Jez
#ifndef OSGPARTICLE_FORCEOPERATOR_
#define OSGPARTICLE_FORCEOPERATOR_ 1
#include <osgParticle/ModularProgram>
#include <osgParticle/Operator>
#include <osgParticle/Particle>
#include <osg/CopyOp>
#include <osg/Object>
#include <osg/Vec3>
namespace osgParticle
{
/** An operator that applies a constant force to the particles.
Remember that if the mass of particles is expressed in <U>kg</U> and the lengths are
expressed in <U>meters</U>, then the force should be expressed in <U>Newtons</U>.
*/
class ForceOperator: public Operator {
public:
inline ForceOperator();
inline ForceOperator(const ForceOperator &copy, const osg::CopyOp &copyop = osg::CopyOp::SHALLOW_COPY);
META_Object(osgParticle, ForceOperator);
/// Get the force vector.
inline const osg::Vec3 &getForce() const;
/// Set the force vector.
inline void setForce(const osg::Vec3 &f);
/// Apply the force to a particle. Do not call this method manually.
inline void operate(Particle *P, double dt);
/// Perform some initialization. Do not call this method manually.
inline void beginOperate(Program *prg);
protected:
virtual ~ForceOperator() {};
ForceOperator &operator=(const ForceOperator &) { return *this; }
private:
osg::Vec3 force_;
osg::Vec3 xf_force_;
};
// INLINE FUNCTIONS
inline ForceOperator::ForceOperator()
: Operator(), force_(0, 0, 0)
{
}
inline ForceOperator::ForceOperator(const ForceOperator &copy, const osg::CopyOp &copyop)
: Operator(copy, copyop), force_(copy.force_)
{
}
inline const osg::Vec3 &ForceOperator::getForce() const
{
return force_;
}
inline void ForceOperator::setForce(const osg::Vec3 &v)
{
force_ = v;
}
inline void ForceOperator::operate(Particle *P, double dt)
{
P->addVelocity(xf_force_ * (P->getMassInv() * dt));
}
inline void ForceOperator::beginOperate(Program *prg)
{
if (prg->getReferenceFrame() == ModularProgram::RELATIVE_TO_PARENTS) {
xf_force_ = prg->rotateLocalToWorld(force_);
} else {
xf_force_ = force_;
}
}
}
#endif