#ifndef _SHADERS_DEFERREDAMBIENT_INC_FX_
#define _SHADERS_DEFERREDAMBIENT_INC_FX_
#include "Ambient.inc.fx"
#if defined(XBOX360_TARGET) || defined(PS3_TARGET)
#define READ_3D_TEXTURES
#endif
#define PROBE_VOLUME_SIZE_Z 17
#define LINEARZSPACING 3.5f
float3 GetUnifiedVolumeUVW(in float3 worldSpacePosition, float baseZ)
{
// Figure out where we stand in the our 3x3 grid (128m per tile).
float2 distFromCenter = worldSpacePosition.xy - VolumeCentreGlobal.xy;
float2 uv = (distFromCenter / (256.0f / 23.0f * 120.0f)) + 0.5f;
// Since we have 24x24 probes, but we have 1 row/column of redundancy between
// tiles, we need to introduce a 1px offset for each tile as we move away
// from the center.
uv += round(distFromCenter / 256.0f) / 120.0f;
float w = saturate((worldSpacePosition.z - baseZ) / LINEARZSPACING / PROBE_VOLUME_SIZE_Z);
return float3(uv, w);
}
// This is al ultra dumbed-down version of what there is in DeferredAmbient.fx,
// designed for rain light. Assumes normal pointing up and no floor correction.
float3 GetRainLightProbeAmbient( float3 worldSpacePos )
{
float3 volumeUVW = GetUnifiedVolumeUVW(worldSpacePos.xyz, CenterBaseZ);
float4 finalUVW4 = float4(volumeUVW, 0);
finalUVW4.z += (0.5f / PROBE_VOLUME_SIZE_Z);
#ifdef READ_3D_TEXTURES
#ifdef NOMAD_PLATFORM_XENON
// On XBOX, since the texture filtering is good, we stick to
// 8-bit texture. We dont use gamma because this would require us
// to use one of the _AS_16 format the the shader becomes
// texture cache stall bound. We opt for a manual (non-gamma-correct)
// filtering using a sqrt() for encoding and x^2 for decoding.
float4 encodedUpperColor = tex3Dlod(BigProbeVolumeTextureUpperColor3D,finalUVW4);
float3 upperColor = (encodedUpperColor.rgb * encodedUpperColor.rgb) / (encodedUpperColor.a * RelightingMultiplier.y);
#else
float3 upperColor = tex3Dlod(BigProbeVolumeTextureUpperColor3D,finalUVW4).xyz;
#endif
#else
// This is PC only, who cares.
float3 upperColor = DefaultProbeUpperColor;
#endif
return upperColor;
}
#endif // _SHADERS_DEFERREDAMBIENT_INC_FX_
