/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 Robert Osfield 
 * Copyright (C) 2003 3Dlabs Inc. Ltd.
 *
 * This application is open source and may be redistributed and/or modified   
 * freely and without restriction, both in commericial and non commericial
 * applications, as long as this copyright notice is maintained.
 * 
 * This application 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.
*/

/* file:	include/osgGL2/UniformValue
 * author:	Mike Weiblen 2003-09-18
 *
 * See http://www.3dlabs.com/opengl2/ for more information regarding
 * the OpenGL Shading Language.
*/

#ifndef OSGGL2_UNIFORMVALUE
#define OSGGL2_UNIFORMVALUE 1

#include <osg/ref_ptr>
#include <osg/Vec2>
#include <osg/Vec3>
#include <osg/Vec4>
#include <osg/Referenced>

#include <osgGL2/Extensions>

#include <vector>


namespace osgGL2 {

///////////////////////////////////////////////////////////////////////////

/** An abstract class to encapsulate a new value for a glUniform.
  * osgGL2::ProgramObject.setUniform() constructs and sends a UniformValue
  * to all its PCPOs (per-context glProgramObjects) to set the value of a
  * glUniform; that value is propogated to the glProgramObjects during the
  * next osgGL2::ProgramObject.apply().
  * This class is for internal use by osgGL2::ProgramObject.
  */

class UniformValue : public osg::Referenced
{
    public:
	virtual void apply( Extensions *ext, const GLhandleARB progObj ) const = 0;

    protected:
	UniformValue( const char* uniformName ) : _name( uniformName ) {};
	virtual ~UniformValue() {};

	int getLocation( Extensions *ext, const GLhandleARB progObj ) const;

	std::string _name;
};

typedef std::vector< osg::ref_ptr<UniformValue> > UniformValueList;


///////////////////////////////////////////////////////////////////////////

#define META_UniformValue( typeName ) \
class UniformValue_##typeName : public UniformValue \
{ \
    public: \
	UniformValue_##typeName( const char* uniformName, typeName value ); \
	virtual void apply( Extensions *ext, const GLhandleARB progObj ) const; \
    protected: \
	typeName _value; \
}

META_UniformValue( int );
META_UniformValue( float );

using namespace osg;
META_UniformValue( Vec2 );
META_UniformValue( Vec3 );
META_UniformValue( Vec4 );

}

#endif

/*EOF*/