Fixes left hand not animating correctly when not mirrored

JasonShaojiesun · Jun 1, 2024 · 883efb9 · 883efb9
1 parent aa9e169
commit 883efb9
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Showing 3 changed files with 33 additions and 7 deletions.
diff --git a/OpenXRExpansionPlugin/Source/OpenXRExpansionPlugin/Private/AnimNode_ApplyOpenXRHandPose.cpp b/OpenXRExpansionPlugin/Source/OpenXRExpansionPlugin/Private/AnimNode_ApplyOpenXRHandPose.cpp
@@ -29,9 +29,28 @@ void FAnimNode_ApplyOpenXRHandPose::OnInitializeAnimInstance(const FAnimInstance
 {
 	Super::OnInitializeAnimInstance(InProxy, InAnimInstance);
 
-	if (const UOpenXRAnimInstance * animInst = Cast<UOpenXRAnimInstance>(InAnimInstance))
+	if (const UOpenXRAnimInstance * OpenXRAnimInstance = Cast<UOpenXRAnimInstance>(InAnimInstance))
 	{
 		bIsOpenInputAnimationInstance = true;
+
+		if (OpenXRAnimInstance->AnimInstanceProxy.HandSkeletalActionData.Num())
+		{
+			for (int i = 0; i < OpenXRAnimInstance->AnimInstanceProxy.HandSkeletalActionData.Num(); ++i)
+			{
+				EVRSkeletalHandIndex TargetHand = OpenXRAnimInstance->AnimInstanceProxy.HandSkeletalActionData[i].TargetHand;
+
+				if (OpenXRAnimInstance->AnimInstanceProxy.HandSkeletalActionData[i].bMirrorLeftRight)
+				{
+					TargetHand = (TargetHand == EVRSkeletalHandIndex::EActionHandIndex_Left) ? EVRSkeletalHandIndex::EActionHandIndex_Right : EVRSkeletalHandIndex::EActionHandIndex_Left;
+				}
+
+				if (TargetHand == MappedBonePairs.TargetHand)
+				{
+					bIsMirroringHand = OpenXRAnimInstance->AnimInstanceProxy.HandSkeletalActionData[i].bMirrorLeftRight;
+					break;
+				}
+			}
+		}
 	}
 }
 
@@ -168,7 +187,16 @@ void FAnimNode_ApplyOpenXRHandPose::CalculateOpenXRAdjustment()
 
 	// Side direction
 	// Do I need to flip this for left hand?
-	static FVector OpenXRSideDirection = FVector(0.f, 1.f, 0.f); 
+
+	bool bUseLeftHandOffsets = false;
+	if ((!bIsMirroringHand && MappedBonePairs.TargetHand == EVRSkeletalHandIndex::EActionHandIndex_Left) ||
+		(bIsMirroringHand && MappedBonePairs.TargetHand == EVRSkeletalHandIndex::EActionHandIndex_Right))
+	{
+		bUseLeftHandOffsets = true;
+	}
+
+	//static FVector OpenXRSideDirection = FVector(0.f, 1.f, 0.f);
+	FVector OpenXRSideDirection = bUseLeftHandOffsets ? FVector(0.f, -1.f, 0.f) : FVector(0.f, 1.f, 0.f);
 
 	// Align forward vectors, openXR once in engine is X+ forward
 	FQuat AlignmentRot = FQuat::FindBetweenNormals(WristForwardLS_UE, OpenXRForwardDirection);
@@ -380,9 +408,6 @@ void FAnimNode_ApplyOpenXRHandPose::EvaluateSkeletalControl_AnyThread(FComponent
 		return;
 	}
 
-
-
-
 	FTransform trans = FTransform::Identity;
 	OutBoneTransforms.Reserve(MappedBonePairs.BonePairs.Num());
 	TArray<FBoneTransform> TransBones;

diff --git a/OpenXRExpansionPlugin/Source/OpenXRExpansionPlugin/Public/AnimNode_ApplyOpenXRHandPose.h b/OpenXRExpansionPlugin/Source/OpenXRExpansionPlugin/Public/AnimNode_ApplyOpenXRHandPose.h
@@ -42,7 +42,8 @@ struct OPENXREXPANSIONPLUGIN_API FAnimNode_ApplyOpenXRHandPose : public FAnimNod
 	UPROPERTY(EditAnywhere, Category = Skeletal, meta = (PinHiddenByDefault))
 		FBPOpenXRSkeletalMappingData MappedBonePairs;
 
-	bool bIsOpenInputAnimationInstance;
+	bool bIsOpenInputAnimationInstance = false;
+	bool bIsMirroringHand = false;
 
 	void ConvertHandTransformsSpace(TArray<FTransform>& OutTransforms, const TArray<FTransform>& WorldTransforms, FTransform AddTrans, bool bMirrorLeftRight, bool bMergeMissingUE4Bones);
 

diff --git a/OpenXRExpansionPlugin/Source/OpenXRExpansionPlugin/Public/OpenXRExpansionTypes.h b/OpenXRExpansionPlugin/Source/OpenXRExpansionPlugin/Public/OpenXRExpansionTypes.h
@@ -103,7 +103,7 @@ struct OPENXREXPANSIONPLUGIN_API FBPOpenXRActionSkeletalData
 	UPROPERTY(EditAnywhere, NotReplicated, BlueprintReadWrite, Category = Default)
 		bool bAllowDeformingMesh;
 
-	// If true then the bones will be mirrored from left/right, to allow you to swap a hand mesh or apply to a full body mesh
+	// If true then the bones will be mirrored from left/right, to allow you to swap a hand mesh to the other hand
 	UPROPERTY(EditAnywhere, NotReplicated, BlueprintReadWrite, Category = Default)
 		bool bMirrorLeftRight;