UnrealEngineUWP/Engine/Plugins/Runtime/Metasound/Source/MetasoundStandardNodes/Private/MetasoundDecibelsToLinearGain.cpp

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

#include "Internationalization/Text.h"
#include "MetasoundFacade.h"
#include "MetasoundExecutableOperator.h"
#include "MetasoundNodeRegistrationMacro.h"
#include "MetasoundPrimitives.h"
#include "MetasoundStandardNodesNames.h"
#include "MetasoundStandardNodesCategories.h"
#include "DSP/Dsp.h"
#include "MetasoundParamHelper.h"

#define LOCTEXT_NAMESPACE "MetasoundStandardNodes_DecibelsToLinearGain"

namespace Metasound
{

	namespace DecibelsToLinearGainVertexNames
	{
		METASOUND_PARAM(InputDecibelGain, "Decibels", "Input logarithmic (dB) gain.");

		METASOUND_PARAM(OutputLinearGain, "Linear Gain", "Output corresponding linear gain.");
	}


	class FDecibelsToLinearGainOperator : public TExecutableOperator<FDecibelsToLinearGainOperator>
	{
	public:

		static const FNodeClassMetadata& GetNodeInfo();
		static const FVertexInterface& GetVertexInterface();
		static TUniquePtr<IOperator> CreateOperator(const FCreateOperatorParams& InParams, FBuildErrorArray& OutErrors);

		FDecibelsToLinearGainOperator(const FOperatorSettings& InSettings, const FFloatReadRef& InDecibelGain);

		virtual FDataReferenceCollection GetInputs() const override;
		virtual FDataReferenceCollection GetOutputs() const override;
		void Execute();

	private:
		// The input dB value
		FFloatReadRef DecibelGainInput;

		// The output linear gain
		FFloatWriteRef LinearGainOutput;
	};

	FDecibelsToLinearGainOperator::FDecibelsToLinearGainOperator(const FOperatorSettings& InSettings, const FFloatReadRef& InDecibelGain)
		: DecibelGainInput(InDecibelGain)
		, LinearGainOutput(FFloatWriteRef::CreateNew(Audio::ConvertToLinear(*InDecibelGain)))
	{
	}

	
	FDataReferenceCollection FDecibelsToLinearGainOperator::GetInputs() const
	{
		using namespace DecibelsToLinearGainVertexNames;

		FDataReferenceCollection InputDataReferences;
		InputDataReferences.AddDataReadReference(METASOUND_GET_PARAM_NAME(InputDecibelGain), DecibelGainInput);

		return InputDataReferences;
	}

	FDataReferenceCollection FDecibelsToLinearGainOperator::GetOutputs() const
	{
		using namespace DecibelsToLinearGainVertexNames;

		FDataReferenceCollection OutputDataReferences;
		OutputDataReferences.AddDataReadReference(METASOUND_GET_PARAM_NAME(OutputLinearGain), LinearGainOutput);
		return OutputDataReferences;
	}

	void FDecibelsToLinearGainOperator::Execute()
	{
		*LinearGainOutput = Audio::ConvertToLinear(*DecibelGainInput);
	}

	const FVertexInterface& FDecibelsToLinearGainOperator::GetVertexInterface()
	{
		using namespace DecibelsToLinearGainVertexNames;

		static const FVertexInterface Interface(
			FInputVertexInterface(
				TInputDataVertex<float>(METASOUND_GET_PARAM_NAME_AND_METADATA(InputDecibelGain), 0.0f)
			),
			FOutputVertexInterface(
				TOutputDataVertex<float>(METASOUND_GET_PARAM_NAME_AND_METADATA(OutputLinearGain))
			)
		);

		return Interface;
	}

	const FNodeClassMetadata& FDecibelsToLinearGainOperator::GetNodeInfo()
	{
		auto InitNodeInfo = []() -> FNodeClassMetadata
		{
			const FName DataTypeName = GetMetasoundDataTypeName<float>();
			const FName OperatorName = TEXT("Decibels to Linear Gain");
			const FText NodeDisplayName = METASOUND_LOCTEXT("Metasound_DecibelsToLinearGainName", "Decibels to Linear Gain");
			const FText NodeDescription = METASOUND_LOCTEXT("Metasound_DecibelsToLinearGainDescription", "Converts a logarithmic (dB) gain value to a linear gain value.");

			FNodeClassMetadata Info;
			Info.ClassName = { StandardNodes::Namespace, OperatorName, DataTypeName };
			Info.MajorVersion = 1;
			Info.MinorVersion = 0;
			Info.DisplayName = NodeDisplayName;
			Info.Description = NodeDescription;
			Info.Author = PluginAuthor;
			Info.PromptIfMissing = PluginNodeMissingPrompt;
			Info.DefaultInterface = GetVertexInterface();
			Info.CategoryHierarchy.Emplace(NodeCategories::Dynamics);

			return Info;
		};

		static const FNodeClassMetadata Info = InitNodeInfo();

		return Info;
	}

	TUniquePtr<IOperator> FDecibelsToLinearGainOperator::CreateOperator(const FCreateOperatorParams& InParams, FBuildErrorArray& OutErrors)
	{
		using namespace DecibelsToLinearGainVertexNames;

		const FDataReferenceCollection& InputCollection = InParams.InputDataReferences;
		const FInputVertexInterface& InputInterface = GetVertexInterface().GetInputInterface();

		FFloatReadRef InDecibelGain = InputCollection.GetDataReadReferenceOrConstructWithVertexDefault<float>(InputInterface, METASOUND_GET_PARAM_NAME(InputDecibelGain), InParams.OperatorSettings);

		return MakeUnique<FDecibelsToLinearGainOperator>(InParams.OperatorSettings, InDecibelGain);
	}

	class METASOUNDSTANDARDNODES_API FDecibelsToLinearGainNode : public FNodeFacade
	{
	public:
		/**
		 * Constructor used by the Metasound Frontend.
		 */
		FDecibelsToLinearGainNode(const FNodeInitData& InitData)
			: FNodeFacade(InitData.InstanceName, InitData.InstanceID, TFacadeOperatorClass <FDecibelsToLinearGainOperator>())
		{
		}
	};

	METASOUND_REGISTER_NODE(FDecibelsToLinearGainNode)
}

#undef LOCTEXT_NAMESPACE