C++ FQuat::IsNormalized方法代码示例

FQuat FAnimNode_RotationMultiplier::ExtractAngle(const TArray<FTransform> & RefPoseTransforms, FA2CSPose & MeshBases, const EBoneAxis Axis,  int32 SourceBoneIndex)
{
	// local bone transform
	const FTransform & LocalBoneTransform = MeshBases.GetLocalSpaceTransform(SourceBoneIndex);
	// local bone transform with reference rotation
	FTransform ReferenceBoneTransform = RefPoseTransforms[SourceBoneIndex];
	ReferenceBoneTransform.SetTranslation(LocalBoneTransform.GetTranslation());

	// find delta angle between the two quaternions X Axis.
	const FVector RotationAxis = GetAxisVector(Axis);
	const FVector LocalRotationVector = LocalBoneTransform.GetRotation().RotateVector(RotationAxis);
	const FVector ReferenceRotationVector = ReferenceBoneTransform.GetRotation().RotateVector(RotationAxis);

	const FQuat LocalToRefQuat = FQuat::FindBetween(LocalRotationVector, ReferenceRotationVector);
	checkSlow( LocalToRefQuat.IsNormalized() );

	// Rotate parent bone atom from position in local space to reference skeleton
	// Since our rotation rotates both vectors with shortest arc
	// we're essentially left with a quaternion that has angle difference with reference skeleton version
	const FQuat BoneQuatAligned = LocalToRefQuat * LocalBoneTransform.GetRotation();
	checkSlow( BoneQuatAligned.IsNormalized() );

	// Find that delta angle
	const FQuat DeltaQuat = (ReferenceBoneTransform.GetRotation().Inverse()) * BoneQuatAligned;
	checkSlow( DeltaQuat.IsNormalized() );

#if 0 //DEBUG_TWISTBONECONTROLLER
	UE_LOG(LogSkeletalControl, Log, TEXT("\t ExtractAngle, Bone: %s (%d)"), 
		*SourceBone.BoneName.ToString(), SourceBoneIndex);
	UE_LOG(LogSkeletalControl, Log, TEXT("\t\t Bone Quat: %s, Rot: %s, AxisX: %s"), *LocalBoneTransform.GetRotation().ToString(), *LocalBoneTransform.GetRotation().Rotator().ToString(), *LocalRotationVector.ToString() );
	UE_LOG(LogSkeletalControl, Log, TEXT("\t\t BoneRef Quat: %s, Rot: %s, AxisX: %s"), *ReferenceBoneTransform.GetRotation().ToString(), *ReferenceBoneTransform.GetRotation().Rotator().ToString(), *ReferenceRotationVector.ToString() );
	UE_LOG(LogSkeletalControl, Log, TEXT("\t\t LocalToRefQuat Quat: %s, Rot: %s"), *LocalToRefQuat.ToString(), *LocalToRefQuat.Rotator().ToString() );

	const FVector BoneQuatAlignedX = LocalBoneTransform.GetRotation().RotateVector(RotationAxis);
	UE_LOG(LogSkeletalControl, Log, TEXT("\t\t BoneQuatAligned Quat: %s, Rot: %s, AxisX: %s"), *BoneQuatAligned.ToString(), *BoneQuatAligned.Rotator().ToString(), *BoneQuatAlignedX.ToString() );
	UE_LOG(LogSkeletalControl, Log, TEXT("\t\t DeltaQuat Quat: %s, Rot: %s"), *DeltaQuat.ToString(), *DeltaQuat.Rotator().ToString() );

	FTransform BoneAtomAligned(BoneQuatAligned, ReferenceBoneTransform.GetTranslation());
	const FQuat DeltaQuatAligned = FQuat::FindBetween(BoneAtomAligned.GetScaledAxis( EAxis::X ), ReferenceBoneTransform.GetScaledAxis( EAxis::X ));
	UE_LOG(LogSkeletalControl, Log, TEXT("\t\t DeltaQuatAligned Quat: %s, Rot: %s"), *DeltaQuatAligned.ToString(), *DeltaQuatAligned.Rotator().ToString() );
	FVector DeltaAxis;
	float	DeltaAngle;
	DeltaQuat.ToAxisAndAngle(DeltaAxis, DeltaAngle);
	UE_LOG(LogSkeletalControl, Log, TEXT("\t\t DeltaAxis: %s, DeltaAngle: %f"), *DeltaAxis.ToString(), DeltaAngle );
#endif

	return DeltaQuat;
}

//.........这里部分代码省略.........
				{
					FABRIKChainLink & CurrentLink = Chain[LinkIndex];
					FABRIKChainLink const & ChildLink = Chain[LinkIndex + 1];

					CurrentLink.Position = ChildLink.Position + (CurrentLink.Position - ChildLink.Position).GetUnsafeNormal() * ChildLink.Length;
				}

				// "Backward Reaching" stage - adjust bones from root.
				for (int32 LinkIndex = 1; LinkIndex < TipBoneLinkIndex; LinkIndex++)
				{
					FABRIKChainLink const & ParentLink = Chain[LinkIndex - 1];
					FABRIKChainLink & CurrentLink = Chain[LinkIndex];

					CurrentLink.Position = ParentLink.Position + (CurrentLink.Position - ParentLink.Position).GetUnsafeNormal() * CurrentLink.Length;
				}

				// Re-check distance between tip location and effector location
				// Since we're keeping tip on top of effector location, check with its parent bone.
				Slop = FMath::Abs(Chain[TipBoneLinkIndex].Length - FVector::Dist(Chain[TipBoneLinkIndex - 1].Position, CSEffectorLocation));
			}

			// Place tip bone based on how close we got to target.
			{
				FABRIKChainLink const & ParentLink = Chain[TipBoneLinkIndex - 1];
				FABRIKChainLink & CurrentLink = Chain[TipBoneLinkIndex];

				CurrentLink.Position = ParentLink.Position + (CurrentLink.Position - ParentLink.Position).GetUnsafeNormal() * CurrentLink.Length;
			}

			bBoneLocationUpdated = true;
		}
	}

	// If we moved some bones, update bone transforms.
	if (bBoneLocationUpdated)
	{
		// First step: update bone transform positions from chain links.
		for (int32 LinkIndex = 0; LinkIndex < NumChainLinks; LinkIndex++)
		{
			FABRIKChainLink const & ChainLink = Chain[LinkIndex];
			OutBoneTransforms[ChainLink.TransformIndex].Transform.SetTranslation(ChainLink.Position);

			// If there are any zero length children, update position of those
			int32 const NumChildren = ChainLink.ChildZeroLengthTransformIndices.Num();
			for (int32 ChildIndex = 0; ChildIndex < NumChildren; ChildIndex++)
			{
				OutBoneTransforms[ChainLink.ChildZeroLengthTransformIndices[ChildIndex]].Transform.SetTranslation(ChainLink.Position);
			}
		}

		// FABRIK algorithm - re-orientation of bone local axes after translation calculation
		for (int32 LinkIndex = 0; LinkIndex < NumChainLinks - 1; LinkIndex++)
		{
			FABRIKChainLink const & CurrentLink = Chain[LinkIndex];
			FABRIKChainLink const & ChildLink = Chain[LinkIndex + 1];

			// Calculate pre-translation vector between this bone and child
			FVector const OldDir = (GetCurrentLocation(MeshBases, ChildLink.BoneIndex) - GetCurrentLocation(MeshBases, CurrentLink.BoneIndex)).GetUnsafeNormal();

			// Get vector from the post-translation bone to it's child
			FVector const NewDir = (ChildLink.Position - CurrentLink.Position).GetUnsafeNormal();

			// Calculate axis of rotation from pre-translation vector to post-translation vector
			FVector const RotationAxis = FVector::CrossProduct(OldDir, NewDir).GetSafeNormal();
			float const RotationAngle = FMath::Acos(FVector::DotProduct(OldDir, NewDir));
			FQuat const DeltaRotation = FQuat(RotationAxis, RotationAngle);
			// We're going to multiply it, in order to not have to re-normalize the final quaternion, it has to be a unit quaternion.
			checkSlow(DeltaRotation.IsNormalized());

			// Calculate absolute rotation and set it
			FTransform& CurrentBoneTransform = OutBoneTransforms[CurrentLink.TransformIndex].Transform;
			CurrentBoneTransform.SetRotation(DeltaRotation * CurrentBoneTransform.GetRotation());

			// Update zero length children if any
			int32 const NumChildren = CurrentLink.ChildZeroLengthTransformIndices.Num();
			for (int32 ChildIndex = 0; ChildIndex < NumChildren; ChildIndex++)
			{
				FTransform& ChildBoneTransform = OutBoneTransforms[CurrentLink.ChildZeroLengthTransformIndices[ChildIndex]].Transform;
				ChildBoneTransform.SetRotation(DeltaRotation * ChildBoneTransform.GetRotation());
			}
		}
	}

	// Special handling for tip bone's rotation.
	int32 const TipBoneTransformIndex = OutBoneTransforms.Num() - 1;
	switch (EffectorRotationSource)
	{
	case BRS_KeepLocalSpaceRotation:
		OutBoneTransforms[TipBoneTransformIndex].Transform = MeshBases.GetLocalSpaceTransform(BoneIndices[TipBoneTransformIndex]) * OutBoneTransforms[TipBoneTransformIndex - 1].Transform;
		break;
	case BRS_CopyFromTarget:
		OutBoneTransforms[TipBoneTransformIndex].Transform.SetRotation(CSEffectorTransform.GetRotation());
		break;
	case BRS_KeepComponentSpaceRotation:
		// Don't change the orientation at all
		break;
	default:
		break;
	}
}