OpenSceneGraph/include/osg/AlphaFunc
2002-01-29 14:04:06 +00:00

84 lines
2.4 KiB
Plaintext

//C++ header - Open Scene Graph - Copyright (C) 1998-2001 Robert Osfield
//Distributed under the terms of the GNU Library General Public License (LGPL)
//as published by the Free Software Foundation.
#ifndef OSG_ALPHAFUNC
#define OSG_ALPHAFUNC 1
#include <osg/StateAttribute>
#include <osg/StateSet>
namespace osg {
/** Encapsulate OpenGL glAlphaFunc.
*/
class SG_EXPORT AlphaFunc : public StateAttribute
{
public :
AlphaFunc();
/** Copy constructor using CopyOp to manage deep vs shallow copy.*/
AlphaFunc(const AlphaFunc& af,const CopyOp& copyop=CopyOp::SHALLOW_COPY):
StateAttribute(af,copyop),
_comparisonFunc(af._comparisonFunc),
_referenceValue(af._referenceValue) {}
META_StateAttribute(AlphaFunc,ALPHAFUNC);
/** return -1 if *this < *rhs, 0 if *this==*rhs, 1 if *this>*rhs.*/
virtual int compare(const StateAttribute& sa) const
{
// check the types are equal and then create the rhs variable
// used by the COMPARE_StateAttribute_Paramter macro's below.
COMPARE_StateAttribute_Types(AlphaFunc,sa)
// compare each paramter in turn against the rhs.
COMPARE_StateAttribute_Parameter(_comparisonFunc)
COMPARE_StateAttribute_Parameter(_referenceValue)
return 0; // passed all the above comparison macro's, must be equal.
}
virtual void setStateSetModes(StateSet& ds,const GLModeValue value) const
{
ds.setMode(GL_ALPHA_TEST,value);
}
enum ComparisonFunction {
NEVER = GL_NEVER,
LESS = GL_LESS,
EQUAL = GL_EQUAL,
LEQUAL = GL_LEQUAL,
GREATER = GL_GREATER,
NOTEQUAL = GL_NOTEQUAL,
GEQUAL = GL_GEQUAL,
ALWAYS = GL_ALWAYS
};
inline void setFunction(const ComparisonFunction func,const float ref)
{
_comparisonFunc = func;
_referenceValue = ref;
}
inline const ComparisonFunction getFunction() const { return _comparisonFunc; }
inline const float getReferenceValue() const { return _referenceValue; }
virtual void apply(State& state) const;
protected:
virtual ~AlphaFunc();
ComparisonFunction _comparisonFunc;
float _referenceValue;
};
};
#endif