// Copyright 1998-2014 Epic Games, Inc. All Rights Reserved.

/*=============================================================================
	BasePassCommon.usf: Base pass definitions used by both vertex and pixel shader
=============================================================================*/

#undef NEEDS_LIGHTMAP_COORDINATE

#define NEEDS_LIGHTMAP_COORDINATE		(HQ_TEXTURE_LIGHTMAP || LQ_TEXTURE_LIGHTMAP)
// Translucent materials need to compute fogging in the forward shading pass
// Materials that read from scene color skip getting fogged, because the contents of the scene color lookup have already been fogged
// This is not foolproof, as any additional color the material adds will then not be fogged correctly
#define NEEDS_BASEPASS_FOGGING			(ENABLE_TRANSLUCENCY_VERTEX_FOG && ((MATERIALBLENDING_TRANSLUCENT || MATERIALBLENDING_ADDITIVE || MATERIALBLENDING_MODULATE) && !MATERIAL_USES_SCENE_COLOR_COPY))
#define NEEDS_LIGHTMAP					(NEEDS_LIGHTMAP_COORDINATE)

struct FSharedBasePassInterpolants
{
	//for texture-lightmapped translucency we can pass the vertex fog in its own interpolator
	#if NEEDS_BASEPASS_FOGGING
		float4 VertexFog		: TEXCOORD6;
	#endif

	#if !PC_D3D && !GL4_PROFILE
		float4 PixelPosition	: TEXCOORD7;

#if USE_WORLD_POSITION_EXCLUDING_SHADER_OFFSETS
		float4 PixelPositionExcludingWPO : TEXCOORD8;
#endif

	#endif
};

#if PC_D3D || GL4_PROFILE

/** Interpolants passed from the vertex shader to the pixel shader. */
struct FBasePassInterpolantsVSToPS : FSharedBasePassInterpolants
{
	float4 PixelPosition	: TEXCOORD7;

#if USE_WORLD_POSITION_EXCLUDING_SHADER_OFFSETS
	float4 PixelPositionExcludingWPO : TEXCOORD8;
#endif
};

/** Interpolants passed from the vertex shader to the domain shader. */
struct FBasePassInterpolantsVSToDS : FSharedBasePassInterpolants
{
#if USE_WORLD_POSITION_EXCLUDING_SHADER_OFFSETS
	float3 WorldPositionExcludingWPO : TEXCOORD8;
#endif
};

#else

// Only the PC shader compiler supports HLSL inheritance
#define FBasePassInterpolantsVSToPS FSharedBasePassInterpolants

#endif