source: GTP/trunk/App/Demos/Vis/FriendlyCulling/src/shaders/combineSsao.cg @ 3109

#include "../shaderenv.h"


struct fragment
{
        float2 texCoord: TEXCOORD0; 
        float3 view: TEXCOORD1;
};


struct pixel
{
        float4 illum_col: COLOR0;
};



float Filter(float2 texCoord, 
                         uniform sampler2D ssaoTex,
                         uniform float2 filterOffs[NUM_SSAO_FILTERSAMPLES],
                         uniform float filterWeights[NUM_SSAO_FILTERSAMPLES])
{
        float average = .0f;
        float w = .0f;

        for (int i = 0; i < NUM_SSAO_FILTERSAMPLES; ++ i)
        {
                average += filterWeights[i] * tex2Dlod(ssaoTex, float4(texCoord + filterOffs[i], 0, 0)).x;
                w += filterWeights[i];
        }

        average *= 1.0f / (float)w;

        return average;
}


float BilateralFilter(float2 texCoord,
                                          float4 ao,
                                          uniform sampler2D ssaoTex,
                                          uniform sampler2D normalsTex,
                                          uniform float2 filterOffs[NUM_SSAO_FILTERSAMPLES],
                                          uniform float filterWeights[NUM_SSAO_FILTERSAMPLES])
{
        float average = .0f;
        float total_w = .0f;

        //const float eyeSpaceDepth = ao.w;
        const float3 norm = normalize(tex2Dlod(normalsTex, float4(texCoord, 0, 0)).xyz);

        float4 aoSample;
        float3 sampleNorm;
        float w;

        for (int i = 0; i < NUM_SSAO_FILTERSAMPLES; ++ i)
        {
                float4 offs = float4(texCoord + filterOffs[i], 0, 0);
                aoSample = tex2Dlod(ssaoTex, offs);
                //aoSample = tex2D(ssaoTex, texCoord + filterOffs[i]);
                //float sampleEyeSpaceDepth = aoSample.w;
                //factor = abs(eyeSpaceDepth - sampleEyeSpaceDepth) / eyeSpaceDepth;
                sampleNorm = normalize(tex2Dlod(normalsTex, offs).xyz);
                //sampleNorm = tex2Dlod(normalsTex, offs).xyz;

                w = filterWeights[i] * max(dot(sampleNorm, norm), .0f);

                average += w * aoSample.x;
                total_w += w;
        }

        average *= 1.0f / max(total_w, 1e-5f);

        return average;
}


pixel combine(fragment IN, 
                          uniform sampler2D colorsTex,
                          uniform sampler2D ssaoTex,
                          uniform sampler2D normalsTex,
                          uniform float2 filterOffs[NUM_SSAO_FILTERSAMPLES],
                          uniform float filterWeights[NUM_SSAO_FILTERSAMPLES]
                          )
{
        pixel OUT;

        float4 col = tex2Dlod(colorsTex, float4(IN.texCoord, 0, 0));
        float4 ao = tex2Dlod(ssaoTex, float4(IN.texCoord, 0, 0));

        //if (ao.y < 10.0f) ao.x = Filter(IN.texCoord, ssaoTex, filterOffs, filterWeights);
        //if (ao.y < 10.0f) ao.x = BilateralFilter(IN.texCoord, ao, ssaoTex, normalsTex, filterOffs, filterWeights);

        //OUT.illum_col = col * ao.x;
        //OUT.illum_col = float4(ao.x, ao.y, ao.z, col.w);
        OUT.illum_col = float4(ao.x, ao.x, ao.x, col.w);
        //OUT.illum_col.xyz = float3(1.0f - ao.x, 1.0f - ao.y * 1e-2f, 1);
        //OUT.illum_col.xyz = float3(1.0f - ao.x, ao.y, 0);
        OUT.illum_col.w = col.w;

        return OUT;
}