struct VS_out { float4 Position : POSITION; float3 TexCoord0 : TEXCOORD0; float2 TexCoord1 : TEXCOORD1; float4 Color : COLOR0; }; sampler2D diffTex : register(s0); sampler2D envTex : register(s1); float4 fogColor : register(c0); float shininess : register(c1); float4 colorClamp : register(c2); float4 main(VS_out input) : COLOR { float4 pass1 = input.Color; #ifdef TEX pass1 *= tex2D(diffTex, input.TexCoord0.xy); #endif float4 envColor = max(pass1, colorClamp); float4 pass2 = envColor*shininess*tex2D(envTex, input.TexCoord1.xy); pass1.rgb = lerp(fogColor.rgb, pass1.rgb, input.TexCoord0.z); // We simulate drawing this in two passes. // First pass with standard blending, second with addition // We premultiply alpha so render state should be one. float4 color; color.rgb = pass1.rgb*pass1.a + pass2.rgb; color.a = pass1.a; return color; }