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sglPositionalLight.hpp

/*****************************************************************************
 * SGL: A Scene Graph Library
 *
 * Copyright (C) 1997-2001  Scott McMillan   All Rights Reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * 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 GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *****************************************************************************
 *     File: sglPositionalLight.hpp
 *   Author: Scott McMillan
 *  Created: 9 December 2000
 *  Summary: encapsulates a positional (local?) light source
 *****************************************************************************/

#ifndef __SGL_POSITIONAL_LIGHT_HPP
#define __SGL_POSITIONAL_LIGHT_HPP

#include <sgl.h>
#include <sglLight.hpp>

//----------------------------------------------------------------------------

class SGL_DLL_API sglPositionalLight : public sglLight
{
public:
   sglPositionalLight();
   virtual ~sglPositionalLight();

   void setPosition(const sglVec3f &pos);

   void getPosition(sglVec3f &pos) const;

   void setAttenuation(float constant, float linear, float quadratic);

   void getAttenuation(float &constant, float &linear, float &quadratic) const;

   void setFalloff(float falloff);

   float getFalloff() const { return 1.0f/m_falloff_inverse; }

   // See sglLight::setup() for details.
   virtual void setup(GLenum gl_light_number) const;

   // See sglNode::clone(..) for details.
   virtual sglNode *clone(unsigned int mode) const;

   // See sglObject::printInfo() for details.
   virtual void printInfo(ostream &ostrm, const char *indent_string) const;

protected:
   virtual void computeBound();

   void copyTo(sglPositionalLight *dst, unsigned int mode) const;

private: // methods - not implemented
   sglPositionalLight(const sglPositionalLight &);
   sglPositionalLight &operator=(const sglPositionalLight &);

protected: // variables
   sglVec4f m_position;

   float    m_attenuation_constant;
   float    m_attenuation_linear;
   float    m_attenuation_quadratic;

   float    m_falloff_inverse;
};

#endif

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