sampler2D samp0 : register(s0);

const float3 const0 : register(c0);
const float4 const4 : register(c4);

struct PSInput
{
    float4 v0 : COLOR0; // vertex color + vertex alpha
    float4 v1 : COLOR1; // blend color (used in xfc)
    float2 t0 : TEXCOORD0; // texcoord
    float4 t1 : TEXCOORD1; // fog being passed from VS to PS
};

float4 xfc(in float4 s0, in float3 s1, in float4 s2, in float4 s3, in float s6)
{
    const float3 outRGB = (s0 * s1 + (1.0f - s0) * s2 + s3).rgb;
    const float outA = s6;
    return float4(outRGB, outA);
}

float4 main(PSInput input) : COLOR0
{
    const float4 texColor = tex2D(samp0, input.t0); // tex t0
    const float3 multipliedColor = texColor.rgb * const0; // mul t0.rgb, t0.rgb, c0.rgb
    const float3 vertexCombinedColor = (input.v0.rgb * multipliedColor) * 4.0f; // mul_x4 r0.rgb, v0.rgb, t0.rgb
    const float multipliedAlpha = (input.v0.a * texColor.a) * 2.0f; // mul_x2 r0.a, v0.a, t0.a
    const float4 combinedResult = float4(vertexCombinedColor, multipliedAlpha);
    const float4 fog = input.t1;
    return xfc( (1 - fog.a) * const4, // prod = s4 * s5
               fog.rgb, // fog.rgb
               combinedResult + input.v1, // sum = r0 + v1
               0.0f, // zero
               multipliedAlpha); // r0.a
}