/**************************************************************************\
 * Copyright (c) Kongsberg Oil & Gas Technologies AS
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 * 
 * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 
 * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
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 * this software without specific prior written permission.
 * 
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\**************************************************************************/

#ifndef COIN_INTERNAL
#error this is a private header file
#endif /* !COIN_INTERNAL */

#ifndef SO_POINTLIGHT_GLSL_H
#define SO_POINTLIGHT_GLSL_H

static const char POINTLIGHT_shadersource[] =
  "\n"
  "void PointLight(in int i,\n"
  "                in vec3 eye,\n"
  "                in vec3 ecPosition3,\n"
  "                in vec3 normal,\n"
  "                inout vec4 ambient,\n"
  "                inout vec4 diffuse,\n"
  "                inout vec4 specular)\n"
  "{\n"
  "  float nDotVP;\n"
  "  float nDotHV;\n"
  "  float pf;  \n"
  "  float att;\n"
  "  float d;          \n"
  "  vec3 VP;\n"
  "  vec3 halfvec;\n"
  "\n"
  "  VP = vec3(gl_LightSource[i].position) - ecPosition3;\n"
  "  d = length(VP);\n"
  "  \n"
  "  VP = normalize(VP);\n"
  "  \n"
  "  att = 1.0 / (gl_LightSource[i].constantAttenuation +\n"
  "               gl_LightSource[i].linearAttenuation * d +\n"
  "               gl_LightSource[i].quadraticAttenuation * d * d);\n"
  "  \n"
  "  halfvec = normalize(VP + eye);\n"
  "  nDotVP = max(0.0, dot(normal, VP));\n"
  "  nDotHV = max(0.0, dot(normal, halfvec));\n"
  "  \n"
  "  float shininess = gl_FrontMaterial.shininess;\n"
  "\n"
  "  if (nDotVP == 0.0)\n"
  "    pf = 0.0;\n"
  "  else \n"
  "    pf = pow(nDotHV, shininess);\n"
  "  \n"
  "  ambient += gl_LightSource[i].ambient * att;\n"
  "  diffuse += gl_LightSource[i].diffuse * nDotVP * att;\n"
  "  specular += gl_LightSource[i].specular * pf * att;\n"
  "}\n";

#endif /* ! SO_POINTLIGHT_GLSL_H */
