#include "Macros.fxh" // from FNA

DECLARE_TEXTURE(gPosition, 0);
DECLARE_TEXTURE(gAlbedo, 1);

BEGIN_CONSTANTS

float3 AmbientLightColor _ps(c0)   _cb(c0);

END_CONSTANTS

struct VertexInput
{
    float4 Position : POSITION;
    float2 TexCoord : TEXCOORD;
};

struct PixelInput
{
    float4 Position : SV_POSITION;
    float2 TexCoord : TEXCOORD0;
};

PixelInput main_vs(VertexInput input)
{
    PixelInput output;

    output.Position = input.Position;
    output.TexCoord = input.TexCoord;

    return output;
}

float4 ComputeColor(
    float3 worldPosition,
    float3 albedo
) {
    float3 color = AmbientLightColor * albedo;
    return float4(color, 1.0);
}

float4 main_ps(PixelInput input) : SV_TARGET0
{
    float3 worldPosition = SAMPLE_TEXTURE(gPosition, input.TexCoord).rgb;
    float3 albedo = SAMPLE_TEXTURE(gAlbedo, input.TexCoord).rgb;

    return ComputeColor(
        worldPosition,
        albedo
    );
}

Technique DeferredPBR_Ambient
{
    Pass
    {
        VertexShader = compile vs_3_0 main_vs();
        PixelShader = compile ps_3_0 main_ps();
    }
}