430 lines
19 KiB
Text
430 lines
19 KiB
Text
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#version 150 compatibility
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uniform bool local_viewer = false;
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uniform int lights_enabled[gl_MaxLights]; // tells about the state of the lights (whether they are enabled or not)
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/**
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* Computes the lighting calculations for a directional light.
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*
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* \param lightSource the light source for which to do the lighting
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* \param lightModelProduct the light product for the light source
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* \param normal the surface normal for the fragment
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* \param ambient the ambient factor in which to write the new ambient factor
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* \param diffuse the diffuse factor in which to write the new diffuse factor
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* \param specular the specular factor in which to write the new specular factor
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*/
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void computeDirectionalLight(in gl_LightSourceParameters lightSource,
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in gl_LightProducts lightProduct,
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in vec3 normal,
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inout vec4 ambient,
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inout vec4 diffuse,
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inout vec4 specular)
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{
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float diffuseFactor = max(dot(normal, normalize(vec3(lightSource.position))), 0.0);
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float specularFactor = 0.0;
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if (diffuseFactor > 0.0)
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{
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specularFactor = max(dot(normal, vec3(lightSource.halfVector)), 0.0);
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specularFactor = pow(specularFactor, gl_FrontMaterial.shininess);
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}
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ambient += lightProduct.ambient;
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diffuse += lightSource.diffuse * diffuseFactor;
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specular += lightProduct.specular * specularFactor;
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}
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/**
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* Computes the lighting calculations for a directional light in the Phong illumination modell.
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*
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* \param lightSource the light source for which to do the lighting
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* \param lightModelProduct the light product for the light source
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* \param normal the surface normal for the fragment
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* \param ambient the ambient factor in which to write the new ambient factor
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* \param diffuse the diffuse factor in which to write the new diffuse factor
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* \param specular the specular factor in which to write the new specular factor
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*/
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void computeDirectionalLightPhong(in gl_LightSourceParameters lightSource,
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in gl_LightProducts lightProduct,
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in vec3 viewVector,
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in vec3 normal,
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inout vec4 ambient,
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inout vec4 diffuse,
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inout vec4 specular)
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{
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vec3 lightVector = normalize(vec3(lightSource.position));
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float diffuseFactor = max(dot(normal, lightVector), 0.0);
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float specularFactor = 0.0;
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if (diffuseFactor > 0.0)
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{
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vec3 reflectVector = 2.0*dot(normal,lightVector)*normal - lightVector;
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specularFactor = max(dot(reflectVector, viewVector), 0.0);
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specularFactor = pow(specularFactor, gl_FrontMaterial.shininess);
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}
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ambient += lightProduct.ambient;
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diffuse += lightSource.diffuse * diffuseFactor;
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specular += lightProduct.specular * specularFactor;
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}
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/**
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* Computes the lighting calculations for a point light.
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*
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* \param lightSource the light source for which to do the lighting
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* \param lightModelProduct the light product for the light source
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* \param viewVector the viewing vector
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* \param position the position of the fragment in eye coordinate space
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* \param normal the surface normal for the fragment
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* \param ambient the ambient factor in which to write the new ambient factor
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* \param diffuse the diffuse factor in which to write the new diffuse factor
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* \param specular the specular factor in which to write the new specular factor
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*/
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void computePointLight(in gl_LightSourceParameters lightSource,
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in gl_LightProducts lightProduct,
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in vec3 viewVector,
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in vec3 position,
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in vec3 normal,
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inout vec4 ambient,
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inout vec4 diffuse,
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inout vec4 specular)
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{
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vec3 lightVec = lightSource.position.xyz / lightSource.position.w - position; // vector from fragment to light source
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float distance = length(lightVec); // distance between surface and light position
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lightVec = normalize(lightVec);
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// attenuation factor
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float attenuation = 1.0 / (lightSource.constantAttenuation +
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lightSource.linearAttenuation * distance +
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lightSource.quadraticAttenuation * distance * distance);
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float diffuseFactor = max(dot(normal, lightVec), 0.0);
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float specularFactor = 0.0;
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if (diffuseFactor > 0.0)
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{
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vec3 halfVector = normalize(lightVec + viewVector);
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specularFactor = max(dot(normal, halfVector), 0.0);
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specularFactor = pow(specularFactor, gl_FrontMaterial.shininess);
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}
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ambient += lightProduct.ambient * attenuation;
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diffuse += lightSource.diffuse * diffuseFactor * attenuation;
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specular += lightProduct.specular * specularFactor * attenuation;
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}
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/**
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* Computes the lighting calculations for a point light.
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*
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* \param lightSource the light source for which to do the lighting
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* \param lightModelProduct the light product for the light source
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* \param viewVector the viewing vector
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* \param position the position of the fragment in eye coordinate space
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* \param normal the surface normal for the fragment
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* \param ambient the ambient factor in which to write the new ambient factor
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* \param diffuse the diffuse factor in which to write the new diffuse factor
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* \param specular the specular factor in which to write the new specular factor
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*/
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void computePointLightPhong(in gl_LightSourceParameters lightSource,
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in gl_LightProducts lightProduct,
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in vec3 viewVector,
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in vec3 position,
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in vec3 normal,
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inout vec4 ambient,
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inout vec4 diffuse,
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inout vec4 specular)
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{
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vec3 lightVec = lightSource.position.xyz / lightSource.position.w - position; // vector from fragment to light source
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float distance = length(lightVec); // distance between surface and light position
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lightVec = normalize(lightVec);
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// attenuation factor
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float attenuation = 1.0 / (lightSource.constantAttenuation +
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lightSource.linearAttenuation * distance +
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lightSource.quadraticAttenuation * distance * distance);
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float diffuseFactor = max(dot(normal, lightVec), 0.0);
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float specularFactor = 0.0;
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if (diffuseFactor > 0.0)
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{
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vec3 reflectVector = 2.0*dot(normal,lightVec)*normal - lightVec;
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specularFactor = max(dot(reflectVector, viewVector), 0.0);
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specularFactor = pow(specularFactor, gl_FrontMaterial.shininess);
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}
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ambient += lightProduct.ambient * attenuation;
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diffuse += lightSource.diffuse * diffuseFactor * attenuation;
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specular += lightProduct.specular * specularFactor * attenuation;
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}
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/**
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* Computes the lighting calculations for a spot light.
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*
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* \param lightSource the light source for which to do the lighting
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* \param lightModelProduct the light product for the light source
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* \param viewVector the viewing vector
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* \param position the position of the fragment in eye coordinate space
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* \param normal the surface normal for the fragment
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* \param ambient the ambient factor in which to write the new ambient factor
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* \param diffuse the diffuse factor in which to write the new diffuse factor
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* \param specular the specular factor in which to write the new specular factor
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*/
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void computeSpotLight(in gl_LightSourceParameters lightSource,
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in gl_LightProducts lightProduct,
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in vec3 viewVector,
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in vec3 position,
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in vec3 normal,
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inout vec4 ambient,
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inout vec4 diffuse,
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inout vec4 specular)
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{
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vec3 lightVec = lightSource.position.xyz / lightSource.position.w - position; // vector from fragment to light source
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float distance = length(lightVec); // distance between surface and light position
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lightVec = normalize(lightVec);
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// see if point on surface is inside cone of illumination
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float spotDot = dot(-lightVec, normalize(lightSource.spotDirection));
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if (spotDot >= lightSource.spotCosCutoff)
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{ // light adds contribution
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// attenuation factor
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float attenuation = 1.0 / (lightSource.constantAttenuation +
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lightSource.linearAttenuation * distance +
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lightSource.quadraticAttenuation * distance * distance);
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// combine the spotlight and distance attenuation
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if (lightSource.spotExponent != 0.0)
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attenuation *= pow(spotDot, lightSource.spotExponent);
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float diffuseFactor = max(0.0, dot(normal, lightVec));
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float specularFactor = 0.0;
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if (diffuseFactor > 0.0)
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{
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vec3 halfVector = normalize(lightVec + viewVector);
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specularFactor = max(0.0, dot(normal, halfVector));
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specularFactor = pow(specularFactor, gl_FrontMaterial.shininess);
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}
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ambient += lightProduct.ambient * attenuation;
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diffuse += lightSource.diffuse * diffuseFactor * attenuation;
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specular += lightProduct.specular * specularFactor * attenuation;
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}
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}
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/**
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* Computes the lighting calculations for a spot light.
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*
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* \param lightSource the light source for which to do the lighting
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* \param lightModelProduct the light product for the light source
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* \param viewVector the viewing vector
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* \param position the position of the fragment in eye coordinate space
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* \param normal the surface normal for the fragment
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* \param ambient the ambient factor in which to write the new ambient factor
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* \param diffuse the diffuse factor in which to write the new diffuse factor
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* \param specular the specular factor in which to write the new specular factor
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*/
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void computeSpotLightPhong(in gl_LightSourceParameters lightSource,
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in gl_LightProducts lightProduct,
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in vec3 viewVector,
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in vec3 position,
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in vec3 normal,
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inout vec4 ambient,
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inout vec4 diffuse,
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inout vec4 specular)
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{
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vec3 lightVec = lightSource.position.xyz / lightSource.position.w - position; // vector from fragment to light source
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float distance = length(lightVec); // distance between surface and light position
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lightVec = normalize(lightVec);
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// see if point on surface is inside cone of illumination
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float spotDot = dot(-lightVec, normalize(lightSource.spotDirection));
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if (spotDot >= lightSource.spotCosCutoff)
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{ // light adds contribution
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// attenuation factor
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float attenuation = 1.0 / (lightSource.constantAttenuation +
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lightSource.linearAttenuation * distance +
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lightSource.quadraticAttenuation * distance * distance);
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// combine the spotlight and distance attenuation
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if (lightSource.spotExponent != 0.0)
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attenuation *= pow(spotDot, lightSource.spotExponent);
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float diffuseFactor = max(0.0, dot(normal, lightVec));
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float specularFactor = 0.0;
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if (diffuseFactor > 0.0)
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{
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vec3 reflectVector = 2.0*dot(normal,lightVec)*normal - lightVec;
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specularFactor = max(dot(reflectVector, viewVector), 0.0);
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specularFactor = pow(specularFactor, gl_FrontMaterial.shininess);
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}
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ambient += lightProduct.ambient * attenuation;
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diffuse += lightSource.diffuse * diffuseFactor * attenuation;
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specular += lightProduct.specular * specularFactor * attenuation;
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}
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}
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/**
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* Does the lighting calculation.
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*
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* \param position the position of the fragment in eye coordinates
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* \param normal the normal of the fragment in eye coordinates
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* \param diffuseMaterial the diffuse material color
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* \return the fragment color resulting from illumination computations
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*/
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vec4 doTwoSidedLighting(vec3 position, vec3 normal, vec4 diffuseMaterial, int side)
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{
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// http://www.opengl.org/sdk/docs/man/xhtml/glNormal.xml
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normal = normalize(normal); // if GL_NORMALIZE is enabled (Page 217); makes no sense here
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// normal = normal * gl_NormalScale; // if GL_RESCALE_NORMAL is enabled (Page 217); makes no sense here
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// http://www.opengl.org/sdk/docs/man/xhtml/glLightModel.xml
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vec3 viewVector = vec3(0.0, 0.0, 1.0); // not local viewer
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if (local_viewer)
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viewVector = -normalize(position); // if GL_LIGHT_MODEL_LOCAL_VIEWER is set to != 0 (Page 222)
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vec4 ambient = vec4(0.0); // ambient color (variant 1) / factor (variant 2)
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vec4 diffuse = vec4(0.0); // diffuse color (variant 1) / factor (variant 2)
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vec4 specular = vec4(0.0); // specular color (variant 1) / factor (variant 2)
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for (int i = 0; i < gl_MaxLights; i++)
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{
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//if (enabled[i] == 1)
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if (lights_enabled[i] == 1)
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{
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if (gl_LightSource[i].position.w == 0.0)
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computeDirectionalLight(gl_LightSource[i], side == 1 ? gl_FrontLightProduct[i] : gl_BackLightProduct[i], normal, ambient, diffuse, specular);
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else if (gl_LightSource[i].spotCutoff == 180.0)
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computePointLight(gl_LightSource[i], side == 1 ? gl_FrontLightProduct[i] : gl_BackLightProduct[i], viewVector, position, normal, ambient, diffuse, specular);
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else
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computeSpotLight(gl_LightSource[i], side == 1 ? gl_FrontLightProduct[i] : gl_BackLightProduct[i], viewVector, position, normal, ambient, diffuse, specular);
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}
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}
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// sceneColor = Ecm + Acm * Acs
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// 'Ecm' == gl_FrontMaterial.emission
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// 'Acm' == gl_FrontMaterial.ambient
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// 'Acs' = ambient color of scene (set through 'glLightModelfv(GL_LIGHT_MODEL_AMBIENT, sceneAmbient);')
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return (side == 1 ? gl_FrontLightModelProduct.sceneColor : gl_BackLightModelProduct.sceneColor) + ambient + diffuseMaterial * diffuse + specular;
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}
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/**
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* Does the lighting calculation.
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*
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* \param position the position of the fragment in eye coordinates
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* \param normal the normal of the fragment in eye coordinates
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* \param diffuseMaterial the diffuse material color
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* \return the fragment color resulting from illumination computations
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*/
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vec4 doLightingAmb(vec3 position, vec3 normal, vec4 ambientMaterial, vec4 diffuseMaterial)
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{
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// http://www.opengl.org/sdk/docs/man/xhtml/glNormal.xml
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normal = normalize(normal); // if GL_NORMALIZE is enabled (Page 217); makes no sense here
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// normal = normal * gl_NormalScale; // if GL_RESCALE_NORMAL is enabled (Page 217); makes no sense here
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// http://www.opengl.org/sdk/docs/man/xhtml/glLightModel.xml
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vec3 viewVector = vec3(0.0, 0.0, 1.0); // not local viewer
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if (local_viewer)
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viewVector = -normalize(position); // if GL_LIGHT_MODEL_LOCAL_VIEWER is set to != 0 (Page 222)
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vec4 ambient = vec4(0.0); // ambient color (variant 1) / factor (variant 2)
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vec4 diffuse = vec4(0.0); // diffuse color (variant 1) / factor (variant 2)
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vec4 specular = vec4(0.0); // specular color (variant 1) / factor (variant 2)
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for (int i = 0; i < gl_MaxLights; i++)
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{
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//if (enabled[i] == 1)
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if (lights_enabled[i] == 1)
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{
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if (gl_LightSource[i].position.w == 0.0)
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computeDirectionalLight(gl_LightSource[i], gl_FrontLightProduct[i], normal, ambient, diffuse, specular);
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else if (gl_LightSource[i].spotCutoff == 180.0)
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computePointLight(gl_LightSource[i], gl_FrontLightProduct[i], viewVector, position, normal, ambient, diffuse, specular);
|
||
|
|
else
|
||
|
|
computeSpotLight(gl_LightSource[i], gl_FrontLightProduct[i], viewVector, position, normal, ambient, diffuse, specular);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// sceneColor = Ecm + Acm * Acs
|
||
|
|
// 'Ecm' == gl_FrontMaterial.emission
|
||
|
|
// 'Acm' == gl_FrontMaterial.ambient
|
||
|
|
// 'Acs' = ambient color of scene (set through 'glLightModelfv(GL_LIGHT_MODEL_AMBIENT, sceneAmbient);')
|
||
|
|
return gl_FrontLightModelProduct.sceneColor + ambientMaterial * ambient + diffuseMaterial * diffuse + specular;
|
||
|
|
}
|
||
|
|
|
||
|
|
vec4 doLighting(vec3 position, vec3 normal, vec4 diffuseMaterial)
|
||
|
|
{
|
||
|
|
// http://www.opengl.org/sdk/docs/man/xhtml/glNormal.xml
|
||
|
|
normal = normalize(normal); // if GL_NORMALIZE is enabled (Page 217); makes no sense here
|
||
|
|
// normal = normal * gl_NormalScale; // if GL_RESCALE_NORMAL is enabled (Page 217); makes no sense here
|
||
|
|
|
||
|
|
// http://www.opengl.org/sdk/docs/man/xhtml/glLightModel.xml
|
||
|
|
vec3 viewVector = vec3(0.0, 0.0, 1.0); // not local viewer
|
||
|
|
if (local_viewer)
|
||
|
|
viewVector = -normalize(position); // if GL_LIGHT_MODEL_LOCAL_VIEWER is set to != 0 (Page 222)
|
||
|
|
|
||
|
|
vec4 ambient = vec4(0.0); // ambient color (variant 1) / factor (variant 2)
|
||
|
|
vec4 diffuse = vec4(0.0); // diffuse color (variant 1) / factor (variant 2)
|
||
|
|
vec4 specular = vec4(0.0); // specular color (variant 1) / factor (variant 2)
|
||
|
|
|
||
|
|
for (int i = 0; i < gl_MaxLights; i++)
|
||
|
|
{
|
||
|
|
//if (enabled[i] == 1)
|
||
|
|
if (lights_enabled[i] == 1)
|
||
|
|
{
|
||
|
|
if (gl_LightSource[i].position.w == 0.0)
|
||
|
|
computeDirectionalLight(gl_LightSource[i], gl_FrontLightProduct[i], normal, ambient, diffuse, specular);
|
||
|
|
else if (gl_LightSource[i].spotCutoff == 180.0)
|
||
|
|
computePointLight(gl_LightSource[i], gl_FrontLightProduct[i], viewVector, position, normal, ambient, diffuse, specular);
|
||
|
|
else
|
||
|
|
computeSpotLight(gl_LightSource[i], gl_FrontLightProduct[i], viewVector, position, normal, ambient, diffuse, specular);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
// sceneColor = Ecm + Acm * Acs
|
||
|
|
// 'Ecm' == gl_FrontMaterial.emission
|
||
|
|
// 'Acm' == gl_FrontMaterial.ambient
|
||
|
|
// 'Acs' = ambient color of scene (set through 'glLightModelfv(GL_LIGHT_MODEL_AMBIENT, sceneAmbient);')
|
||
|
|
return gl_FrontLightModelProduct.sceneColor + ambient + diffuseMaterial * diffuse + specular;
|
||
|
|
}
|
||
|
|
/**
|
||
|
|
* Does the lighting calculation with the Phong Illumination model.
|
||
|
|
*
|
||
|
|
* \param position the position of the fragment in eye coordinates
|
||
|
|
* \param normal the normal of the fragment in eye coordinates
|
||
|
|
* \param diffuseMaterial the diffuse material color
|
||
|
|
* \return the fragment color resulting from illumination computations
|
||
|
|
*/
|
||
|
|
vec4 doPhongLighting(vec3 position, vec3 normal, vec4 diffuseMaterial)
|
||
|
|
{
|
||
|
|
// http://www.opengl.org/sdk/docs/man/xhtml/glNormal.xml
|
||
|
|
normal = normalize(normal); // if GL_NORMALIZE is enabled (Page 217); makes no sense here
|
||
|
|
// normal = normal * gl_NormalScale; // if GL_RESCALE_NORMAL is enabled (Page 217); makes no sense here
|
||
|
|
|
||
|
|
// http://www.opengl.org/sdk/docs/man/xhtml/glLightModel.xml
|
||
|
|
vec3 viewVector = vec3(0.0, 0.0, 1.0); // not local viewer
|
||
|
|
if (local_viewer)
|
||
|
|
viewVector = -normalize(position); // if GL_LIGHT_MODEL_LOCAL_VIEWER is set to != 0 (Page 222)
|
||
|
|
|
||
|
|
vec4 ambient = vec4(0.0); // ambient color (variant 1) / factor (variant 2)
|
||
|
|
vec4 diffuse = vec4(0.0); // diffuse color (variant 1) / factor (variant 2)
|
||
|
|
vec4 specular = vec4(0.0); // specular color (variant 1) / factor (variant 2)
|
||
|
|
|
||
|
|
for (int i = 0; i < gl_MaxLights; i++)
|
||
|
|
{
|
||
|
|
//if (enabled[i] == 1)
|
||
|
|
if (lights_enabled[i] == 1)
|
||
|
|
{
|
||
|
|
if (gl_LightSource[i].position.w == 0.0)
|
||
|
|
computeDirectionalLightPhong(gl_LightSource[i], gl_FrontLightProduct[i], viewVector, normal, ambient, diffuse, specular);
|
||
|
|
else if (gl_LightSource[i].spotCutoff == 180.0)
|
||
|
|
computePointLightPhong(gl_LightSource[i], gl_FrontLightProduct[i], viewVector, position, normal, ambient, diffuse, specular);
|
||
|
|
else
|
||
|
|
computeSpotLightPhong(gl_LightSource[i], gl_FrontLightProduct[i], viewVector, position, normal, ambient, diffuse, specular);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// sceneColor = Ecm + Acm * Acs
|
||
|
|
// 'Ecm' == gl_FrontMaterial.emission
|
||
|
|
// 'Acm' == gl_FrontMaterial.ambient
|
||
|
|
// 'Acs' = ambient color of scene (set through 'glLightModelfv(GL_LIGHT_MODEL_AMBIENT, sceneAmbient);')
|
||
|
|
return gl_FrontLightModelProduct.sceneColor + ambient + diffuseMaterial * diffuse + specular;
|
||
|
|
}
|