UnrealEngineUWP/Engine/Source/Runtime/RenderCore/Private/ShaderParameterMetadataBuilder.cpp

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

#include "ShaderParameterMetadataBuilder.h"

void FShaderParametersMetadataBuilder::AddReferencedStruct(
	const TCHAR* Name,
	const FShaderParametersMetadata* StructMetadata,
	EShaderPrecisionModifier::Type Precision
)
{
	NextMemberOffset = Align(NextMemberOffset, SHADER_PARAMETER_STRUCT_ALIGNMENT);

	new(Members) FShaderParametersMetadata::FMember(
		Name,
		StructMetadata->GetStructTypeName(),
		__LINE__,
		NextMemberOffset,
		UBMT_REFERENCED_STRUCT,
		Precision,
		1,
		1,
		0,
		StructMetadata
	);

	NextMemberOffset += Align(StructMetadata->GetSize(), SHADER_PARAMETER_STRUCT_ALIGNMENT);
}

uint32 FShaderParametersMetadataBuilder::AddNestedStruct(
	const TCHAR* Name,
	const FShaderParametersMetadata* StructMetadata,
	EShaderPrecisionModifier::Type Precision /* = EShaderPrecisionModifier::Float */
)
{
	NextMemberOffset = Align(NextMemberOffset, SHADER_PARAMETER_STRUCT_ALIGNMENT);
	const uint32 ThisMemberOffset = NextMemberOffset;

	new(Members) FShaderParametersMetadata::FMember(
		Name,
		TEXT(""),
		__LINE__,
		NextMemberOffset,
		UBMT_NESTED_STRUCT,
		Precision,
		1,
		1,
		0,
		StructMetadata
	);

	NextMemberOffset += Align(StructMetadata->GetSize(), SHADER_PARAMETER_STRUCT_ALIGNMENT);
	return ThisMemberOffset;
}

void FShaderParametersMetadataBuilder::AddBufferSRV(
	const TCHAR* Name,
	const TCHAR* ShaderType,
	EShaderPrecisionModifier::Type Precision /* = EShaderPrecisionModifier::Float */
)
{
	NextMemberOffset = Align(NextMemberOffset, SHADER_PARAMETER_POINTER_ALIGNMENT);

	new(Members) FShaderParametersMetadata::FMember(
		Name,
		ShaderType,
		__LINE__,
		NextMemberOffset,
		UBMT_SRV,
		Precision,
		TShaderResourceParameterTypeInfo<FRHIShaderResourceView*>::NumRows,
		TShaderResourceParameterTypeInfo<FRHIShaderResourceView*>::NumColumns,
		TShaderResourceParameterTypeInfo<FRHIShaderResourceView*>::NumElements,
		TShaderResourceParameterTypeInfo<FRHIShaderResourceView*>::GetStructMetadata()
	);

	NextMemberOffset += SHADER_PARAMETER_POINTER_ALIGNMENT;
}

void FShaderParametersMetadataBuilder::AddBufferUAV(
	const TCHAR* Name,
	const TCHAR* ShaderType,
	EShaderPrecisionModifier::Type Precision /* = EShaderPrecisionModifier::Float */
)
{
	NextMemberOffset = Align(NextMemberOffset, SHADER_PARAMETER_POINTER_ALIGNMENT);

	new(Members) FShaderParametersMetadata::FMember(
		Name,
		ShaderType,
		__LINE__,
		NextMemberOffset,
		UBMT_UAV,
		Precision,
		TShaderResourceParameterTypeInfo<FRHIUnorderedAccessView*>::NumRows,
		TShaderResourceParameterTypeInfo<FRHIUnorderedAccessView*>::NumColumns,
		TShaderResourceParameterTypeInfo<FRHIUnorderedAccessView*>::NumElements,
		TShaderResourceParameterTypeInfo<FRHIUnorderedAccessView*>::GetStructMetadata()
	);

	NextMemberOffset += SHADER_PARAMETER_POINTER_ALIGNMENT;
}

void FShaderParametersMetadataBuilder::AddRDGBufferSRV(
	const TCHAR* Name,
	const TCHAR* ShaderType,
	EShaderPrecisionModifier::Type Precision /* = EShaderPrecisionModifier::Float */
	)
{
	NextMemberOffset = Align(NextMemberOffset, SHADER_PARAMETER_POINTER_ALIGNMENT);

	new(Members) FShaderParametersMetadata::FMember(
		Name,
		ShaderType,
		__LINE__,
		NextMemberOffset,
		UBMT_RDG_BUFFER_SRV,
		Precision,
 		TShaderResourceParameterTypeInfo<FRDGBufferSRV*>::NumRows,
 		TShaderResourceParameterTypeInfo<FRDGBufferSRV*>::NumColumns,
 		TShaderResourceParameterTypeInfo<FRDGBufferSRV*>::NumElements,
 		TShaderResourceParameterTypeInfo<FRDGBufferSRV*>::GetStructMetadata()
	);

	NextMemberOffset += SHADER_PARAMETER_POINTER_ALIGNMENT;
}

void FShaderParametersMetadataBuilder::AddRDGBufferUAV(
	const TCHAR* Name,
	const TCHAR* ShaderType,
	EShaderPrecisionModifier::Type Precision /* = EShaderPrecisionModifier::Float */
	)
{
	NextMemberOffset = Align(NextMemberOffset, SHADER_PARAMETER_POINTER_ALIGNMENT);

	new(Members) FShaderParametersMetadata::FMember(
		Name,
		ShaderType,
		__LINE__,
		NextMemberOffset,
		UBMT_RDG_BUFFER_UAV,
		Precision,
 		TShaderResourceParameterTypeInfo<FRDGBufferUAV*>::NumRows,
 		TShaderResourceParameterTypeInfo<FRDGBufferUAV*>::NumColumns,
 		TShaderResourceParameterTypeInfo<FRDGBufferUAV*>::NumElements,
 		TShaderResourceParameterTypeInfo<FRDGBufferUAV*>::GetStructMetadata()
		);

	NextMemberOffset += SHADER_PARAMETER_POINTER_ALIGNMENT;
}

FShaderParametersMetadata* FShaderParametersMetadataBuilder::Build(
	FShaderParametersMetadata::EUseCase UseCase,
	const TCHAR* ShaderParameterName
	)
{
	const uint32 StructSize = Align(NextMemberOffset, SHADER_PARAMETER_STRUCT_ALIGNMENT);

	FShaderParametersMetadata* ShaderParameterMetadata = new FShaderParametersMetadata(
		UseCase,
		EUniformBufferBindingFlags::Shader,
		ShaderParameterName,
		ShaderParameterName,
		nullptr,
		nullptr,
		__FILE__,
		__LINE__,
		StructSize,
		Members
		);

	return ShaderParameterMetadata;
}