// Copyright Epic Games, Inc. All Rights Reserved.

// Include required for platform TANGENT_RWBUFFER_FORMAT.
#include "/Engine/Private/GpuSkinCommon.ush"

uint {DataInterfaceName}_NumVertices;

Buffer<float> {DataInterfaceName}_PositionBufferSRV;
Buffer<TANGENT_RWBUFFER_FORMAT> {DataInterfaceName}_TangentBufferSRV;
Buffer<UNORM float4> {DataInterfaceName}_ColorBufferSRV;

Buffer<float> {DataInterfaceName}_PositionStaticBuffer;
Buffer<TANGENT_RWBUFFER_FORMAT> {DataInterfaceName}_TangentStaticBuffer;
Buffer<UNORM float4> {DataInterfaceName}_ColorStaticBuffer;
uint {DataInterfaceName}_ColorIndexMask;

uint ReadNumVertices_{DataInterfaceName}()
{
	return {DataInterfaceName}_NumVertices;
}

float3 ReadPosition_{DataInterfaceName}(uint VertexIndex)
{
	uint BufferIndex = (VertexIndex) * 3;

#if READABLE_OUTPUT_BUFFERS & OPTIMUS_SKINNED_MESH_READ_POSITION
	return float3(
		{DataInterfaceName}_PositionBufferSRV[BufferIndex + 0], 
		{DataInterfaceName}_PositionBufferSRV[BufferIndex + 1],
		{DataInterfaceName}_PositionBufferSRV[BufferIndex + 2]);
#else
	return float3(
		{DataInterfaceName}_PositionStaticBuffer[BufferIndex + 0], 
		{DataInterfaceName}_PositionStaticBuffer[BufferIndex + 1],
		{DataInterfaceName}_PositionStaticBuffer[BufferIndex + 2]);
#endif 
}

float4 ReadTangentX_{DataInterfaceName}(uint VertexIndex)
{
	uint BufferIndex = (VertexIndex) * 2;
	
#if READABLE_OUTPUT_BUFFERS & OPTIMUS_SKINNED_MESH_READ_TANGENTS
	return TangentBias_SkinCache({DataInterfaceName}_TangentBufferSRV[BufferIndex]) ;
#else	
	return TangentBias_SkinCache({DataInterfaceName}_TangentStaticBuffer[BufferIndex]) ;
#endif
}

float4 ReadTangentZ_{DataInterfaceName}(uint VertexIndex)
{
	uint BufferIndex = (VertexIndex) * 2;
#if READABLE_OUTPUT_BUFFERS & OPTIMUS_SKINNED_MESH_READ_TANGENTS
	return TangentBias_SkinCache({DataInterfaceName}_TangentBufferSRV[BufferIndex + 1]) ;
#else	
	return TangentBias_SkinCache({DataInterfaceName}_TangentStaticBuffer[BufferIndex + 1]) ;
#endif
}

float4 ReadColor_{DataInterfaceName}(uint VertexIndex)
{
	// Index Mask is used here in case ColorStaticBuffer is bound to the GWhiteVertexBufferWithSRV that is only a few bytes
	uint BufferIndex = (VertexIndex) & ({DataInterfaceName}_ColorIndexMask);
#if READABLE_OUTPUT_BUFFERS & OPTIMUS_SKINNED_MESH_READ_COLOR
	return {DataInterfaceName}_ColorBufferSRV[BufferIndex] FMANUALFETCH_COLOR_COMPONENT_SWIZZLE;
#else	
	return {DataInterfaceName}_ColorStaticBuffer[BufferIndex] FMANUALFETCH_COLOR_COMPONENT_SWIZZLE;
#endif	
}