OpenSceneGraph/include/osgUtil/Simplifier
Robert Osfield 91516305d9 Added support for protecting points from being simplified.
Added back in support for generation of skirts in osgTerrain::DataSet.
2004-04-22 13:36:30 +00:00

105 lines
4.0 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.
*/
#ifndef OSGUTIL_SIMPLIYFIER
#define OSGUTIL_SIMPLIYFIER 1
#include <osg/NodeVisitor>
#include <osg/Geode>
#include <osg/Geometry>
#include <osgUtil/Export>
namespace osgUtil {
/** A simplifier for reducing the number of traingles in osg::Geometry.
*/
class OSGUTIL_EXPORT Simplifier : public osg::NodeVisitor
{
public:
Simplifier(float sampleRatio=1.0f, float maximumError=0.0f);
void setSampleRatio(float sampleRatio) { _sampleRatio = sampleRatio; }
float getSampleRatio() const { return _sampleRatio; }
void setMaximumError(float error) { _maximumError = error; }
float getMaximumError() const { return _maximumError; }
class ContinueSimplificationCallback : public osg::Referenced
{
public:
/** return true if mesh should be continued to be simplified, return false to stop simplification.*/
virtual bool continueSimplification(const Simplifier& simplifier, float nextError, unsigned int numOriginalPrimitives, unsigned int numRemainingPrimitives) const
{
return simplifier.continueSimplificationImplementation(nextError, numOriginalPrimitives, numRemainingPrimitives);
}
protected:
virtual ~ContinueSimplificationCallback() {}
};
void setContinueSimplificationCallback(ContinueSimplificationCallback* cb) { _continueSimplificationCallback = cb; }
ContinueSimplificationCallback* getContinueSimplificationCallback() { return _continueSimplificationCallback.get(); }
const ContinueSimplificationCallback* getContinueSimplificationCallback() const { return _continueSimplificationCallback.get(); }
bool continueSimplification(float nextError, unsigned int numOriginalPrimitives, unsigned int numRemainingPrimitives) const
{
if (_continueSimplificationCallback.valid()) return _continueSimplificationCallback->continueSimplification(*this, nextError, numOriginalPrimitives, numRemainingPrimitives);
else return continueSimplificationImplementation(nextError, numOriginalPrimitives, numRemainingPrimitives);
}
virtual bool continueSimplificationImplementation(float nextError, unsigned int numOriginalPrimitives, unsigned int numRemainingPrimitives) const
{
if (nextError<=getMaximumError()) return true;
return (float)numRemainingPrimitives > (float)numOriginalPrimitives * getSampleRatio();
}
virtual void apply(osg::Geode& geode)
{
for(unsigned int i=0;i<geode.getNumDrawables();++i)
{
osg::Geometry* geometry = geode.getDrawable(i)->asGeometry();
if (geometry)
{
simplify(*geometry);
}
}
}
/** simply the geometry.*/
void simplify(osg::Geometry& geometry);
typedef std::vector<unsigned int> IndexList; /// a list of point indices
/** simply the geometry, whilst protecting key points from being modified.*/
void simplify(osg::Geometry& geometry, const IndexList& protectedPoints);
protected:
float _sampleRatio;
float _maximumError;
osg::ref_ptr<ContinueSimplificationCallback> _continueSimplificationCallback;
};
}
#endif