UnrealEngineUWP/Engine/Source/Runtime/InteractiveToolsFramework/Public/TargetInterfaces/MeshDescriptionCommitter.h

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

#pragma once

#include "CoreMinimal.h"

#include "MeshDescription.h"
#include "UObject/Interface.h"

#include "MeshDescriptionCommitter.generated.h"

UINTERFACE()
class INTERACTIVETOOLSFRAMEWORK_API UMeshDescriptionCommitter : public UInterface
{
	GENERATED_BODY()
};

class INTERACTIVETOOLSFRAMEWORK_API IMeshDescriptionCommitter
{
	GENERATED_BODY()

public:

	struct FCommitterParams
	{
		/** 
		 * Mesh description that should be populated/updated by the passed-in function and which
		 * will be committed to the target.
		 */
		FMeshDescription* MeshDescriptionOut  = nullptr;
	};
	using  FCommitter = TFunction<void(const FCommitterParams&)>;

	/** 
	 * Commit a mesh description. The mesh description to be committed will be passed to the
	 * given function as a parameter, and it is up to the function to update it properly.
	 *
	 * @param Committer A function that takes in const IMeshDescriptionCommitter::FCommitParams&
	 *  and populates the FMeshDescription pointed to by the MeshDescription pointer inside.
	 */
	virtual void CommitMeshDescription(const FCommitter& Committer) = 0;

	/**
	 * Commits the given FMeshDescription.
	 */
	virtual void CommitMeshDescription(const FMeshDescription& Mesh)
	{
		// It seems reasonable to have this function, but we'll go ahead and give a default implementation
		// if users want to just implement the other one.

		CommitMeshDescription([&Mesh](const FCommitterParams& CommitParams)
		{
			if (CommitParams.MeshDescriptionOut)
			{
				*CommitParams.MeshDescriptionOut = Mesh;
			}
		});
	}
};