void FAnimationRuntime::ConvertPoseToMeshRotation(FCompactPose& LocalPose)
{
// Convert all rotations to mesh space
// only the root bone doesn't have a parent. So skip it to save a branch in the iteration.
for (FCompactPoseBoneIndex BoneIndex(1); BoneIndex < LocalPose.GetNumBones(); ++BoneIndex)
{
const FCompactPoseBoneIndex ParentIndex = LocalPose.GetParentBoneIndex(BoneIndex);
const FQuat MeshSpaceRotation = LocalPose[ParentIndex].GetRotation() * LocalPose[BoneIndex].GetRotation();
LocalPose[BoneIndex].SetRotation(MeshSpaceRotation);
}
}
void FAnimationRuntime::ConvertMeshRotationPoseToLocalSpace(FCompactPose& Pose)
{
// Convert all rotations to mesh space
// only the root bone doesn't have a parent. So skip it to save a branch in the iteration.
for (FCompactPoseBoneIndex BoneIndex(Pose.GetNumBones()-1); BoneIndex > 0; --BoneIndex)
{
const FCompactPoseBoneIndex ParentIndex = Pose.GetParentBoneIndex(BoneIndex);
FQuat LocalSpaceRotation = Pose[ParentIndex].GetRotation().Inverse() * Pose[BoneIndex].GetRotation();
Pose[BoneIndex].SetRotation(LocalSpaceRotation);
}
}
void FAnimationRuntime::BlendPosesTogetherPerBoneInMeshSpace(TArray<FCompactPose>& SourcePoses, const TArray<FBlendedCurve>& SourceCurves, const UBlendSpaceBase* BlendSpace, const TArray<FBlendSampleData>& BlendSampleDataCache, FCompactPose& ResultPose, FBlendedCurve& ResultCurve)
{
FQuat NewRotation;
USkeleton* Skeleton = BlendSpace->GetSkeleton();
// all this is going to do is to convert SourcePoses.Rotation to be mesh space, and then once it goes through BlendPosesTogetherPerBone, convert back to local
for (FCompactPose& Pose : SourcePoses)
{
for (const FCompactPoseBoneIndex BoneIndex : Pose.ForEachBoneIndex())
{
const FCompactPoseBoneIndex ParentIndex = Pose.GetParentBoneIndex(BoneIndex);
if (ParentIndex != INDEX_NONE)
{
NewRotation = Pose[ParentIndex].GetRotation()*Pose[BoneIndex].GetRotation();
NewRotation.Normalize();
}
else
{
NewRotation = Pose[BoneIndex].GetRotation();
}
// now copy back to SourcePoses
Pose[BoneIndex].SetRotation(NewRotation);
}
}
// now we have mesh space rotation, call BlendPosesTogetherPerBone
BlendPosesTogetherPerBone(SourcePoses, SourceCurves, BlendSpace, BlendSampleDataCache, ResultPose, ResultCurve);
// now result atoms has the output with mesh space rotation. Convert back to local space, start from back
for (const FCompactPoseBoneIndex BoneIndex : ResultPose.ForEachBoneIndex())
{
const FCompactPoseBoneIndex ParentIndex = ResultPose.GetParentBoneIndex(BoneIndex);
if (ParentIndex != INDEX_NONE)
{
FQuat LocalBlendQuat = ResultPose[ParentIndex].GetRotation().Inverse()*ResultPose[BoneIndex].GetRotation();
ResultPose[BoneIndex].SetRotation(LocalBlendQuat);
ResultPose[BoneIndex].NormalizeRotation();
}
}
}