source: data/branches/Shader_HS18/programs/GLSL120/Instancing.frag @ 12115

//---------------------------------------------------------------------------
//These materials/shaders are part of the NEW InstanceManager implementation
//Written by Matias N. Goldberg ("dark_sylinc")
//---------------------------------------------------------------------------

uniform sampler2D diffuseMap;

uniform vec4    lightPosition;
uniform vec3    cameraPosition;
uniform vec3    lightAmbient;
uniform vec3    lightDiffuse;
uniform vec3    lightSpecular;
uniform vec4    lightAttenuation;
uniform float   lightGloss;

#if DEPTH_SHADOWRECEIVER
uniform float invShadowMapSize;
uniform sampler2DShadow shadowMap;

//declare external function
//vec4 calcDepthShadow(in vec4 inColour, in float lum);
float calcDepthShadow(sampler2DShadow shadowMap, vec4 uv, float invShadowMapSize);
#endif

varying vec2 _uv0;
varying vec3 oNormal;
varying vec3 oVPos;
#if DEPTH_SHADOWRECEIVER
        varying vec4 oLightSpacePos;
#endif

//---------------------------------------------
//Main Pixel Shader
//---------------------------------------------
void main(void)
{
        vec4 color = texture2D( diffuseMap, _uv0 );

        float fShadow = 1.0;
#if DEPTH_SHADOWRECEIVER
        fShadow = calcDepthShadow( shadowMap, oLightSpacePos, invShadowMapSize );
#endif

        vec4 baseColour = texture2D( diffuseMap, _uv0 );

        //Blinn-Phong lighting
        vec3 normal     = normalize( oNormal );
        vec3 lightDir           = lightPosition.xyz - oVPos * lightPosition.w;
        vec3 eyeDir                     = normalize( cameraPosition - oVPos );

        float fLength   = length( lightDir );
        lightDir                        = normalize( lightDir );

        float NdotL     = max( 0.0, dot( normal, lightDir ) );
        vec3 halfVector         = normalize(lightDir + eyeDir);
        float HdotN     = max( 0.0, dot( halfVector, normal ) );
        
        vec3 ambient  = lightAmbient * baseColour.xyz;
        vec3 diffuse  = lightDiffuse * NdotL * baseColour.xyz;
        vec3 specular = lightSpecular * pow( HdotN, lightGloss );
        
        vec3 directLighting = (diffuse + specular) * fShadow;
        
        gl_FragColor = vec4( directLighting + ambient, baseColour.a );
        //gl_FragColor = baseColour;
}