source: GTP/trunk/App/Demos/Vis/FriendlyCulling/src/shaders/deferred.cg @ 2887

struct fragment
{
         // normalized screen position
        float4 pos: WPOS;
        float4 texCoord: TEXCOORD0; 
        float3 view: COLOR0;
};


struct pixel
{
        float4 color: COLOR0;
};



/** function for standard deferred shading
*/
float4 shade(fragment IN, 
                         uniform float4 color,
                         uniform float4 position,
                         uniform float3 normal,
                         uniform float amb)
{
        float4 lightDir = float4(0.8f, -1.0f, 0.7f, 0.0f);
        //float4 lightDir = float4(0.0f, 1.0f, 0.0f, 0.0f);
        float4 lightDir2 = float4(-0.5f, 0.5f, 0.4f, 0.0f);

        // global ambient
        const float4 ambient = 0.25f;

        // float3 L = normalize(lightPosition - position);
        float3 light = normalize(lightDir.xyz);
        float3 light2 = normalize(lightDir2.xyz);

        float diffuseLight = saturate(dot(normal, light));
        float diffuseLight2 = saturate(dot(normal, light2));

        float diffuse = diffuseLight + diffuseLight2;

        return (ambient + diffuse) * color * (1.0f - amb) + amb * color;
}



/** The mrt shader for standard rendering
*/
pixel main(fragment IN, 
                   uniform sampler2D colors,
                   uniform sampler2D positions,
                   uniform sampler2D normals
                   )
{
        pixel OUT;

        float4 norm = tex2D(normals, IN.texCoord.xy);
        float4 color = tex2Dlod(colors, float4(IN.texCoord.xy, 0, 0));
        float4 position = tex2D(positions, IN.texCoord.xy);

        // an ambient color term
        float amb = norm.w;

        // expand normal
        float3 normal = normalize(norm.xyz);// * 2.0f - float4(1.0f));

        float4 col = shade(IN, color, position, normal, amb);
        
        //OUT.color = float4(1.0f);
        OUT.color = col;
        OUT.color.w = color.w;

        return OUT;
}