OpenSceneGraph/include/osgUtil/HighlightMapGenerator
2006-07-18 15:21:48 +00:00

64 lines
2.0 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_HIGHLIGHTMAPGENERATOR_
#define OSGUTIL_HIGHLIGHTMAPGENERATOR_
#include <osgUtil/Export>
#include <osgUtil/CubeMapGenerator>
namespace osgUtil
{
/** This cube map generator produces a specular highlight map.
* The vector-color association is: C = (R dot (-L)) ^ n, where C is the
* resulting color, R is the reflection vector, L is the light direction
* and n is the specular exponent.
*/
class OSGUTIL_EXPORT HighlightMapGenerator: public CubeMapGenerator {
public:
HighlightMapGenerator(
const osg::Vec3 &light_direction,
const osg::Vec4 &light_color,
float specular_exponent,
int texture_size = 64);
HighlightMapGenerator(const HighlightMapGenerator &copy, const osg::CopyOp &copyop = osg::CopyOp::SHALLOW_COPY);
protected:
virtual ~HighlightMapGenerator() {}
HighlightMapGenerator &operator=(const HighlightMapGenerator &) { return *this; }
inline virtual osg::Vec4 compute_color(const osg::Vec3 &R) const;
private:
osg::Vec3 ldir_;
osg::Vec4 lcol_;
float sexp_;
};
// INLINE METHODS
inline osg::Vec4 HighlightMapGenerator::compute_color(const osg::Vec3 &R) const
{
float v = -ldir_ * (R / R.length());
if (v < 0) v = 0;
osg::Vec4 color(lcol_ * powf(v, sexp_));
color.w() = 1;
return color;
}
}
#endif