OpenSceneGraph/include/osgUtil/Simplifier

130 lines
5.2 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.
*/
#ifndef OSGUTIL_SIMPLIFIER
#define OSGUTIL_SIMPLIFIER 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(double sampleRatio=1.0, double maximumError=FLT_MAX, double maximumLength=0.0);
META_NodeVisitor(osgUtil, Simplifier)
void setSampleRatio(float sampleRatio) { _sampleRatio = sampleRatio; }
float getSampleRatio() const { return _sampleRatio; }
/** Set the maximum point error that all point removals must be less than to permit removal of a point.
* Note, Only used when down sampling. i.e. sampleRatio < 1.0*/
void setMaximumError(float error) { _maximumError = error; }
float getMaximumError() const { return _maximumError; }
/** Set the maximum length target that all edges must be shorted than.
* Note, Only used when up sampling i.e. sampleRatio > 1.0.*/
void setMaximumLength(float length) { _maximumLength = length; }
float getMaximumLength() const { return _maximumLength; }
void setDoTriStrip(bool on) { _triStrip = on; }
bool getDoTriStrip() const { return _triStrip; }
void setSmoothing(bool on) { _smoothing = on; }
bool getSmoothing() const { return _smoothing; }
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);
}
virtual bool requiresDownSampling(const Simplifier& simplifier) const
{
return simplifier.requiresDownSamplingImplementation();
}
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 (getSampleRatio()<1.0) return ((float)numRemainingPrimitives > ((float)numOriginalPrimitives) * getSampleRatio()) && nextError<=getMaximumError();
else return ((float)numRemainingPrimitives < ((float)numOriginalPrimitives) * getSampleRatio()) && nextError>getMaximumLength();
}
bool requiresDownSampling() const
{
if (_continueSimplificationCallback.valid()) return _continueSimplificationCallback->requiresDownSampling(*this);
else return requiresDownSamplingImplementation();
}
virtual bool requiresDownSamplingImplementation() const
{
return getSampleRatio()<1.0;
}
virtual void apply(osg::Geometry& geom)
{
simplify(geom);
}
/** 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:
double _sampleRatio;
double _maximumError;
double _maximumLength;
bool _triStrip;
bool _smoothing;
osg::ref_ptr<ContinueSimplificationCallback> _continueSimplificationCallback;
};
}
#endif