float4x4 mvp : ModelViewProjection;
float4x4 mv : ModelView;
float4x4 mvit : ModelViewIT;

samplerCUBE skybox : SKYBOX;

sampler2D amberTex <string fileName = "amber.jpg";> = sampler_state {
  minFilter = Linear;
  magFilter = Linear;
  wrapS = Repeat;
  wrapT = Repeat;
};

float4 vertex(uniform float4x4 modelViewProj,
              uniform float4x4 modelView,
              uniform float4x4 modelViewIT,
              float4 P : POSITION,
              float4 N : NORMAL,
	          float2 uvIn : TEXCOORD0,
		   in float4 Cin : COLOR0,
              out float4 CC : COLOR0,
              out float3 Pcam : TEXCOORD1,
              out float3 Ncam : TEXCOORD2,
	      out float2 uv : TEXCOORD0) : POSITION
{
    CC.xyz =  normalize(N.xyz);
    Pcam = mul(modelView, P).xyz;
    float3x3 rotation = (float3x3)modelView;
    Ncam.xyz = mul(rotation,N.xyz);
    uv = uvIn;
    return mul(modelViewProj, P);
}


float4 light(in float3 texcoord,
                float3 Pcam : TEXCOORD1, 
                float3 Ncam : TEXCOORD2) : COLOR 
{
   float3 Nn = normalize(Ncam);

   // Reflection and refraction.
   float3 refl = reflect(Pcam,Nn);
   float3 refrRed = refract(Pcam,Nn, 1.3);
   float3 refrYellow = refract(Pcam,Nn,1.5);
    
   float3 reflCol = texCUBE(skybox,refl).rgb;
   reflCol.b = 0;
   
   float3 refrRedCol; 
   refrRedCol.r = texCUBE(skybox,refrRed).r;
   
   float3 refrYellowCol;
   refrYellowCol.r = texCUBE(skybox,refrYellow).r;
   refrYellowCol.g = texCUBE(skybox,refrYellow).g;
   
   float3 refCol = (reflCol + refrRedCol + refrYellowCol) / 3.0;
   
   // Amber Texture:
   float3 amberCol = tex2D(amberTex, texcoord);
   
   // Random factor:
   float3 randomCol = normalize(Pcam);
   randomCol.b *= .25;

   float3 finalCol = (5.0 * refCol + 5.0 * amberCol + 0.0 * randomCol) / 10.0;
   return float4(finalCol, 1);
}

technique red <string target = "both";>
{
	pass p0
	{
 		VertexProgram = compile arbvp1 vertex(mvp, mv, mvit);
 		FragmentProgram = compile arbfp1 light();
	}
}