MeshModelingToolset: Cleanup UV Unwrap tool

#rb ryan.schmidt
#preflight 61a6d63b6c7d8a7295f405a2, 61a92f32fc3f6823e8d2bac7

#ROBOMERGE-AUTHOR: michael.balzer
#ROBOMERGE-SOURCE: CL 18357442 in //UE5/Release-5.0/... via CL 18357499
#ROBOMERGE-BOT: STARSHIP (Release-Engine-Staging -> Release-Engine-Test) (v895-18170469)

[CL 18357514 by michael balzer in ue5-release-engine-test branch]

Engine/Plugins/Runtime/MeshModelingToolset/Source/MeshModelingTools/Public/Properties/MeshUVChannelProperties.h

@@ -0,0 +1,46 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#pragma once
+
+#include "CoreMinimal.h"
+#include "InteractiveTool.h"
+#include "GeometryBase.h"
+#include "MeshUVChannelProperties.generated.h"
+
+struct FMeshDescription;
+PREDECLARE_USE_GEOMETRY_CLASS(FDynamicMesh3);
+
+
+UCLASS()
+class MESHMODELINGTOOLS_API UMeshUVChannelProperties : public UInteractiveToolPropertySet
+{
+	GENERATED_BODY()
+public:
+
+	/** Select UV channel in the mesh */
+	UPROPERTY(EditAnywhere, Category = "UV Channel", meta = (DisplayName = "UV Channel", GetOptions = GetUVChannelNamesFunc, NoResetToDefault))
+	FString UVChannel;
+
+	UFUNCTION()
+	const TArray<FString>& GetUVChannelNamesFunc() const;
+
+	UPROPERTY(meta = (TransientToolProperty))
+	TArray<FString> UVChannelNamesList;
+
+	void Initialize(int32 NumUVChannels, bool bInitializeSelection = true);
+	void Initialize(const FMeshDescription* MeshDescription, bool bInitializeSelection = true);
+	void Initialize(const FDynamicMesh3* Mesh, bool bInitializeSelection = true);
+
+	/**
+	 * Verify that the UV channel selection is valid
+	 * @param bUpdateIfInvalid if selection is not valid, reset UVChannel to UV0 or empty if no UV channels exist
+	 * @return true if selection in UVChannel is an entry in UVChannelNamesList.
+	 */
+	bool ValidateSelection(bool bUpdateIfInvalid);
+
+	/**
+	 * @param bForceToZeroOnFailure if true, then instead of returning -1 we return 0 so calling code can fallback to default UV paths
+	 * @return selected UV channel index, or -1 if invalid selection, or 0 if invalid selection and bool bForceToZeroOnFailure = true
+	 */
+	int32 GetSelectedChannelIndex(bool bForceToZeroOnFailure = false);
+};

Engine/Plugins/Runtime/MeshModelingToolset/Source/MeshModelingTools/Public/RecomputeUVsTool.h

@@ -0,0 +1,93 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#pragma once
+
+#include "CoreMinimal.h"
+#include "BaseTools/SingleSelectionMeshEditingTool.h"
+#include "DynamicMesh/DynamicMesh3.h"
+#include "MeshOpPreviewHelpers.h"
+#include "Properties/MeshMaterialProperties.h"
+#include "Properties/MeshUVChannelProperties.h"
+#include "Properties/RecomputeUVsProperties.h"
+#include "PropertySets/PolygroupLayersProperties.h"
+#include "Polygroups/PolygroupSet.h"
+#include "Drawing/UVLayoutPreview.h"
+
+#include "RecomputeUVsTool.generated.h"
+
+
+// Forward declarations
+class UDynamicMeshComponent;
+class UMaterialInterface;
+class UMaterialInstanceDynamic;
+class RecomputeUVsOp;
+class URecomputeUVsOpFactory;
+
+
+/**
+ *
+ */
+UCLASS()
+class MESHMODELINGTOOLS_API URecomputeUVsToolBuilder : public USingleSelectionMeshEditingToolBuilder
+{
+	GENERATED_BODY()
+
+public:
+	virtual USingleSelectionMeshEditingTool* CreateNewTool(const FToolBuilderState& SceneState) const override;
+};
+
+
+/**
+ * URecomputeUVsTool Recomputes UVs based on existing segmentations of the mesh
+ */
+UCLASS()
+class MESHMODELINGTOOLS_API URecomputeUVsTool : public USingleSelectionMeshEditingTool
+{
+	GENERATED_BODY()
+
+public:
+	virtual void Setup() override;
+	virtual void Shutdown(EToolShutdownType ShutdownType) override;
+
+	virtual void Render(IToolsContextRenderAPI* RenderAPI) override;
+	virtual void OnTick(float DeltaTime) override;
+
+	virtual bool HasCancel() const override { return true; }
+	virtual bool HasAccept() const override { return true; }
+	virtual bool CanAccept() const override;
+
+	virtual void OnPropertyModified(UObject* PropertySet, FProperty* Property) override;
+
+protected:
+	UPROPERTY()
+	TObjectPtr<UMeshUVChannelProperties> UVChannelProperties = nullptr;
+
+	UPROPERTY()
+	TObjectPtr<URecomputeUVsToolProperties> Settings = nullptr;
+
+	UPROPERTY()
+	TObjectPtr<UPolygroupLayersProperties> PolygroupLayerProperties = nullptr;
+
+	UPROPERTY()
+	TObjectPtr<UExistingMeshMaterialProperties> MaterialSettings = nullptr;
+
+	UPROPERTY()
+	bool bCreateUVLayoutViewOnSetup = true;
+
+	UPROPERTY()
+	TObjectPtr<UUVLayoutPreview> UVLayoutView = nullptr;
+
+	UPROPERTY()
+	TObjectPtr<URecomputeUVsOpFactory> RecomputeUVsOpFactory;
+
+	UPROPERTY()
+	TObjectPtr<UMeshOpPreviewWithBackgroundCompute> Preview = nullptr;
+
+	TSharedPtr<UE::Geometry::FDynamicMesh3, ESPMode::ThreadSafe> InputMesh;
+
+	TSharedPtr<UE::Geometry::FPolygroupSet, ESPMode::ThreadSafe> ActiveGroupSet;
+	void OnSelectedGroupLayerChanged();
+	void UpdateActiveGroupLayer();
+	int32 GetSelectedUVChannel() const;
+	void OnPreviewMeshUpdated();
+};