UnrealEngineUWP/Engine/Source/Runtime/AnimGraphRuntime/Private/BoneControllers/AnimNode_SkeletalControlBase.cpp

// Copyright 1998-2015 Epic Games, Inc. All Rights Reserved.

#include "AnimGraphRuntimePrivatePCH.h"
#include "BoneControllers/AnimNode_SkeletalControlBase.h"
#include "AnimationUtils.h"
#include "AnimationRuntime.h"

/////////////////////////////////////////////////////
// FAnimNode_SkeletalControlBase

void FAnimNode_SkeletalControlBase::Initialize(const FAnimationInitializeContext& Context)
{
	ComponentPose.Initialize(Context);
}

void FAnimNode_SkeletalControlBase::CacheBones(const FAnimationCacheBonesContext& Context) 
{
	InitializeBoneReferences(Context.AnimInstance->RequiredBones);
	ComponentPose.CacheBones(Context);
}

void FAnimNode_SkeletalControlBase::Update(const FAnimationUpdateContext& Context)
{
	ComponentPose.Update(Context);
	EvaluateGraphExposedInputs.Execute(Context);
}

bool ContainsNaN(const TArray<FBoneTransform> & BoneTransforms)
{
	for (int32 i = 0; i < BoneTransforms.Num(); ++i)
	{
		if (BoneTransforms[i].Transform.ContainsNaN())
		{
			return true;
		}
	}

	return false;
}

void FAnimNode_SkeletalControlBase::EvaluateComponentSpace(FComponentSpacePoseContext& Output)
{
	// Evaluate the input
	ComponentPose.EvaluateComponentSpace(Output);

	// Apply the skeletal control if it's valid
	const float ActualAlpha = AlphaScaleBias.ApplyTo(Alpha);
	if ((ActualAlpha >= ZERO_ANIMWEIGHT_THRESH) && IsValidToEvaluate(Output.AnimInstance->CurrentSkeleton, Output.AnimInstance->RequiredBones))
	{
		USkeletalMeshComponent* Component = Output.AnimInstance->GetSkelMeshComponent();

#if WITH_EDITORONLY_DATA
		// save current pose before applying skeletal control to compute the exact gizmo location in AnimGraphNode
		ForwardedPose = Output.Pose;
#endif // #if WITH_EDITORONLY_DATA

		TArray<FBoneTransform> BoneTransforms;
		EvaluateBoneTransforms(Component, Output.Pose, BoneTransforms);

		checkSlow(!ContainsNaN(BoneTransforms));

		if (BoneTransforms.Num() > 0)
		{
			const float BlendWeight = FMath::Clamp<float>(ActualAlpha, 0.f, 1.f);
			Output.Pose.LocalBlendCSBoneTransforms(BoneTransforms, BlendWeight);
		}
	}
}

void FAnimNode_SkeletalControlBase::AddDebugNodeData(FString& OutDebugData)
{
	const float ActualAlpha = AlphaScaleBias.ApplyTo(Alpha);
	OutDebugData += FString::Printf(TEXT("Alpha: %.1f%%"), ActualAlpha*100.f);
}