// object shader

#include "hdr.cg"

struct v2f 
{
    float4 HPosition : POSITION;
    float4 P         : TEXCOORD0; // position
    float3 N         : TEXCOORD1; // normal
    float3 I         : TEXCOORD2; // incident vector
};

half4 main(v2f In,
           uniform samplerCUBE envMap : TEXUNIT0) : COLOR
{
    half3 I = normalize(half3(In.I));
    half3 N = normalize(half3(In.N));

    half3 R = reflect(I, N);
//    half3 T = refract(I, N, 0.9);
    half fresnel = my_fresnel(-I, N, 5.0, 0.98, 0.02);

    half3 Creflect = texCUBE(envMap, R).rgb; // lookup reflection in HDR cube map
//    half3 Crefract = texCUBE(envMap, T).rgb; // refraction

//    half3 Cout = lerp(Crefract, Creflect, fresnel);
//    return half4(Cout, fresnel*0.5 + 0.5);

    return half4(Creflect * fresnel, 1.0);
}