A primitive skin weights paint tool for skeletal meshes.

#jira UE-93689
#rb ryan.schmidt
#preflight 60942eeb4a6341000184add9

[CL 16321464 by halfdan ingvarsson in ue5-main branch]

Engine/Plugins/Experimental/MeshModelingToolset/Source/MeshModelingTools/MeshModelingTools.Build.cs

@@ -14,14 +14,12 @@ public class MeshModelingTools : ModuleRules
 			}
 			);
 				
-		
-		PrivateIncludePaths.AddRange(
+		PublicIncludePathModuleNames.AddRange(
 			new string[] {
-				// ... add other private include paths required here ...
+				"AnimationCore",			// For the BoneWeights.h include
 			}
-			);
-			
-		
+		);
+	
 		PublicDependencyModuleNames.AddRange(
 			new string[]
 			{
@@ -42,6 +40,7 @@ public class MeshModelingTools : ModuleRules
 				"MeshConversion",
 				"MeshDescription",
                 "StaticMeshDescription",
+                "SkeletalMeshDescription",
 				"ModelingComponents",
 				"ModelingOperators",
 
@@ -75,7 +74,8 @@ public class MeshModelingTools : ModuleRules
 				"RenderCore",
 				"ModelingOperators",
 				"InputCore",
-				"PhysicsCore"
+				"PhysicsCore",
+
 				// ... add private dependencies that you statically link with here ...
 			}
 			);

Engine/Plugins/Experimental/MeshModelingToolset/Source/MeshModelingTools/Public/SkinWeightsPaintTool.h

@@ -0,0 +1,172 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#pragma once
+
+#include "DynamicMeshBrushTool.h"
+#include "Changes/ValueWatcher.h"
+#include "MeshDescription.h"
+#include "DynamicVerticesOctree3.h"
+#include "BoneContainer.h"
+#include "Interfaces/Interface_BoneReferenceSkeletonProvider.h"
+#include "Misc/Optional.h"
+#include "Containers/Map.h"
+#include "TargetInterfaces/MeshDescriptionCommitter.h"
+
+#include "SkinWeightsPaintTool.generated.h"
+
+
+struct FMeshDescription;
+class USkinWeightsPaintTool;
+class IMeshDescriptionCommitter;
+
+
+
+class MESHMODELINGTOOLS_API FMeshSkinWeightsChange : public FToolCommandChange
+{
+public:
+	FMeshSkinWeightsChange(const FName& InBoneName) :
+		FToolCommandChange(),
+		BoneName(InBoneName)
+	{ }
+
+	virtual FString ToString() const override
+	{
+		return FString(TEXT("Paint Skin Weights"));
+	}
+
+	void Apply(UObject* Object) override;
+
+	void Revert(UObject* Object) override;
+
+	void UpdateValues(const TArray<int32>& Indices, const TArray<float>& OldValues, const TArray<float>& NewValues);
+
+private:
+	FName BoneName;
+	TMap<int32, float> OldWeights;
+	TMap<int32, float> NewWeights;
+};
+
+
+/**
+ *
+ */
+UCLASS()
+class MESHMODELINGTOOLS_API USkinWeightsPaintToolBuilder : public UMeshSurfacePointToolBuilder
+{
+	GENERATED_BODY()
+
+public:
+	UMeshSurfacePointTool* CreateNewTool(const FToolBuilderState& SceneState) const override;
+};
+
+
+UCLASS()
+class MESHMODELINGTOOLS_API USkinWeightsPaintToolProperties : 
+	public UInteractiveToolPropertySet,
+	public IBoneReferenceSkeletonProvider
+{
+	GENERATED_BODY()
+public:
+	UPROPERTY(VisibleAnywhere, Category = Skeleton)
+	FBoneReference CurrentBone;
+
+	// IBoneReferenceSkeletonProvider
+	USkeleton* GetSkeleton(bool& bInvalidSkeletonIsError) override;
+
+	TObjectPtr<USkeletalMesh> SkeletalMesh;
+};
+
+
+/**
+ *
+ */
+UCLASS()
+class MESHMODELINGTOOLS_API USkinWeightsPaintTool : public UDynamicMeshBrushTool
+{
+	GENERATED_BODY()
+
+public:
+	void RegisterActions(FInteractiveToolActionSet& ActionSet) override;
+
+	void Setup() override;
+	void Render(IToolsContextRenderAPI* RenderAPI) override;
+
+	bool HasCancel() const override { return true; }
+	bool HasAccept() const override { return true; }
+	bool CanAccept() const override { return true; }
+
+	// UBaseBrushTool overrides
+	bool HitTest(const FRay& Ray, FHitResult& OutHit) override;
+	void OnBeginDrag(const FRay& Ray) override;
+	void OnUpdateDrag(const FRay& Ray) override;
+	void OnEndDrag(const FRay& Ray) override;
+	bool OnUpdateHover(const FInputDeviceRay& DevicePos) override;
+
+protected:
+
+	virtual void ApplyStamp(const FBrushStampData& Stamp);
+
+	void OnShutdown(EToolShutdownType ShutdownType) override;
+	void OnTick(float DeltaTime) override;
+
+	double CalculateBrushFalloff(double Distance) const;
+	void CalculateVertexROI(const FBrushStampData& Stamp, TArray<int>& VertexROI);
+
+	UPROPERTY()
+	USkinWeightsPaintToolProperties* ToolProps;
+
+	TValueWatcher<FBoneReference> CurrentBoneWatcher;
+
+	bool bInRemoveStroke = false;
+	bool bInSmoothStroke = false;
+	FBrushStampData StartStamp;
+	FBrushStampData LastStamp;
+	bool bStampPending;
+
+	TUniquePtr<FMeshDescription> EditedMesh;
+
+	FBoneContainer BoneContainer;
+
+	UE::Geometry::TDynamicVerticesOctree3<FDynamicMesh3> VerticesOctree;
+	TArray<int> PreviewBrushROI;
+
+	using BoneInfluenceMapType = TMap<FName, TArray<float>>;
+	BoneInfluenceMapType SkinWeightsMap;
+	FName CurrentBone = NAME_None;
+	TOptional<FName> PendingCurrentBone;
+
+
+	bool bVisibleWeightsValid = false;
+
+	static FVector4f WeightToColor(float Value);
+	
+	void InitializeSkinWeights();
+	void UpdateBoneVisualization();
+	void UpdateCurrentBone(const FName &BoneName);
+
+	void ExternalUpdateAttributes(TUniquePtr<TAttributesSet<FVertexID>>& NewAttrib, int32 NewSelecedIndex);
+
+	struct FBonePositionInfo
+	{
+		FName BoneName;
+		int32 ParentBoneIndex;
+		FVector Position;
+		float Radius;
+		TMap<FName, int32> ChildBones;
+	};
+	TArray<FBonePositionInfo> BonePositionInfos;
+	float MaxDrawRadius;
+
+	void UpdateBonePositionInfos(float MinRadius);
+	void RenderBonePositions(FPrimitiveDrawInterface *PDI);
+
+	TUniquePtr<FMeshSkinWeightsChange> ActiveChange;
+
+	void BeginChange();
+	TUniquePtr<FMeshSkinWeightsChange> EndChange();
+
+	friend class FMeshSkinWeightsChange;
+	void ExternalUpdateValues(const FName &BoneName, const TMap<int32, float>& IndexValues);
+
+	void CommitSkinWeights(const IMeshDescriptionCommitter::FCommitterParams& CommitParams);
+};

Engine/Plugins/Experimental/ModelingToolsEditorMode/Source/ModelingToolsEditorMode/Private/ModelingToolsManagerActions.cpp

@@ -101,6 +101,8 @@ void FModelingToolsManagerCommands::RegisterCommands()
 	UI_COMMAND(BeginBakeMeshAttributeMapsTool, "BakeTx", "Bake Image Maps for Target Mesh (optionally from second Source Mesh)", EUserInterfaceActionType::ToggleButton, FInputChord());
 	UI_COMMAND(BeginUVSeamEditTool, "SeamEd", "Add UV Seams to Mesh", EUserInterfaceActionType::ToggleButton, FInputChord());
 
+	UI_COMMAND(BeginSkinWeightsPaintTool, "SkinWts", "Start the Paint Skin Weights Tool", EUserInterfaceActionType::Button, FInputChord());
+
 	UI_COMMAND(BeginGroomToMeshTool, "Helmet", "Generate Helmet Mesh for Selected Groom", EUserInterfaceActionType::ToggleButton, FInputChord());
 	UI_COMMAND(BeginGenerateLODMeshesTool, "HlmLOD", "Generate LODS for Hair Helmet", EUserInterfaceActionType::ToggleButton, FInputChord());
 	UI_COMMAND(BeginGroomCardsToMeshTool, "CardsToMesh", "Hair Cards to Mesh Tool", EUserInterfaceActionType::ToggleButton, FInputChord());

Engine/Plugins/Experimental/ModelingToolsEditorMode/Source/ModelingToolsEditorMode/Public/ModelingToolsManagerActions.h

@@ -92,6 +92,7 @@ public:
 	TSharedPtr<FUICommandInfo> BeginEditMeshMaterialsTool;
 	TSharedPtr<FUICommandInfo> BeginTransformUVIslandsTool;
 	TSharedPtr<FUICommandInfo> BeginMeshAttributePaintTool;
+	TSharedPtr<FUICommandInfo> BeginSkinWeightsPaintTool;
 	TSharedPtr<FUICommandInfo> BeginAttributeEditorTool;
 	TSharedPtr<FUICommandInfo> BeginBakeMeshAttributeMapsTool;
 	TSharedPtr<FUICommandInfo> BeginUVSeamEditTool;