sampler2D textureSampler : register(s0);

float4 backgroundColor;

float4 PixelShaderFunction(float2 coords : TEXCOORD0) : COLOR0
{
    float4 cutoutColor = tex2D(textureSampler, coords);

    float4 finalColor = cutoutColor;

    if (cutoutColor.r > 0 || cutoutColor.g > 0 || cutoutColor.b > 0)
        finalColor = cutoutColor.a = 0;
    else
        finalColor = backgroundColor;

    return finalColor;
}

technique Technique0
{
    pass Pass0
    {
        PixelShader = compile ps_3_0 PixelShaderFunction();
    }
}