RogueLegacy1/RogueCastle/Shaders/BrightPass.fx

uniform extern float BloomThreshold;
float2 halfPixel;
sampler TextureSampler : register(s0);
float4 BrightPassPS(float2 texCoord : TEXCOORD0) : COLOR0
{
    texCoord -= halfPixel;
    // Look up the original image color.
    float4 c = tex2D(TextureSampler, texCoord);
    // Adjust it to keep only values brighter than the specified threshold.
    return saturate((c - BloomThreshold) / (1 - BloomThreshold));
}
technique BloomExtract
{
    pass P0
    {
        PixelShader = compile ps_2_0 BrightPassPS();
    }
}