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Fix root motion on skeletons with different coordinate system

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#3847
This commit is contained in:
mafiesto4
2026-10-01 22:55:27 +02:00
parent 52620b9d80
commit 093a49c76a
2 changed files with 22 additions and 8 deletions
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Source/Engine/Animations/AnimationData.h
+2
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@@ -96,6 +96,8 @@ API_ENUM(Attributes="Flags") enum class AnimationRootMotionFlags : byte
RootPosition = RootPositionXZ | RootPositionY,
// Root node position and rotation.
RootTransform = RootPosition | RootRotation,
// Marks that the root node position is affected by the skeleton transform and should be extracted with transformed mask. Use this option for models that don't use Y-up coordinate system.
LocalPositionMask = 1 << 3,
};
DECLARE_ENUM_OPERATORS(AnimationRootMotionFlags);
Source/Engine/Animations/Graph/AnimGroup.Animation.cpp
+20 -8
View File
@@ -499,9 +499,23 @@ void AnimGraphExecutor::ProcessAnimation(AnimGraphImpulse* nodes, AnimGraphNode*
const bool motionPositionXZ = EnumHasAnyFlags(anim->Data.RootMotionFlags, AnimationRootMotionFlags::RootPositionXZ);
const bool motionPositionY = EnumHasAnyFlags(anim->Data.RootMotionFlags, AnimationRootMotionFlags::RootPositionY);
const bool motionRotation = EnumHasAnyFlags(anim->Data.RootMotionFlags, AnimationRootMotionFlags::RootRotation);
const Vector3 motionPositionMask(motionPositionXZ ? 1.0f : 0.0f, motionPositionY ? 1.0f : 0.0f, motionPositionXZ ? 1.0f : 0.0f);
const bool motionPosition = motionPositionXZ | motionPositionY;
const Vector3 motionPositionMaskRef(motionPositionXZ ? 1.0f : 0.0f, motionPositionY ? 1.0f : 0.0f, motionPositionXZ ? 1.0f : 0.0f);
Vector3 motionPositionMask = motionPositionMaskRef;
const int32 rootNodeIndex = GetRootNodeIndex(anim);
auto& skeleton = _graph.BaseModel->Skeleton;
if (motionPosition && EnumHasAnyFlags(anim->Data.RootMotionFlags, AnimationRootMotionFlags::LocalPositionMask))
{
// Rotate position mask by the rotation of the root node to extract motion in the local space of the model (eg. when skeleton has different coordinate system)
Quaternion rootOrientation = Quaternion::Identity;
int32 parentIndex = skeleton.Nodes[rootNodeIndex].ParentIndex;
while (parentIndex != -1)
{
rootOrientation = rootOrientation * skeleton.Nodes[parentIndex].LocalTransform.Orientation;
parentIndex = skeleton.Nodes[parentIndex].ParentIndex;
}
Vector3::Transform(motionPositionMask, rootOrientation, motionPositionMask);
}
const Transform& refPose = emptyNodes->Nodes[rootNodeIndex];
Transform& rootNode = nodes->Nodes[rootNodeIndex];
Transform& dstNode = nodes->RootMotion;
@@ -545,12 +559,10 @@ void AnimGraphExecutor::ProcessAnimation(AnimGraphImpulse* nodes, AnimGraphNode*
}
// Convert root motion from local-space to the actor-space (eg. if root node is not actually a root and its parents have rotation/scale)
auto& skeleton = _graph.BaseModel->Skeleton;
int32 parentIndex = skeleton.Nodes[rootNodeIndex].ParentIndex;
while (parentIndex != -1)
{
const Transform& parentNode = nodes->Nodes[parentIndex];
srcNode.Translation = parentNode.LocalToWorld(srcNode.Translation);
srcNode.Translation = nodes->Nodes[parentIndex].LocalToWorld(srcNode.Translation);
parentIndex = skeleton.Nodes[parentIndex].ParentIndex;
}
}
@@ -565,28 +577,28 @@ void AnimGraphExecutor::ProcessAnimation(AnimGraphImpulse* nodes, AnimGraphNode*
if (mode == ProcessAnimationMode::BlendAdditive)
{
if (motionPosition)
dstNode.Translation += srcNode.Translation * weight * motionPositionMask;
dstNode.Translation += srcNode.Translation * weight * motionPositionMaskRef;
if (motionRotation)
BlendAdditiveWeightedRotation(dstNode.Orientation, srcNode.Orientation, weight);
}
else if (mode == ProcessAnimationMode::Add)
{
if (motionPosition)
dstNode.Translation += srcNode.Translation * weight * motionPositionMask;
dstNode.Translation += srcNode.Translation * weight * motionPositionMaskRef;
if (motionRotation)
dstNode.Orientation += srcNode.Orientation * weight;
}
else if (weighted)
{
if (motionPosition)
dstNode.Translation = srcNode.Translation * weight * motionPositionMask;
dstNode.Translation = srcNode.Translation * weight * motionPositionMaskRef;
if (motionRotation)
dstNode.Orientation = srcNode.Orientation * weight;
}
else
{
if (motionPosition)
dstNode.Translation = srcNode.Translation * motionPositionMask;
dstNode.Translation = srcNode.Translation * motionPositionMaskRef;
if (motionRotation)
dstNode.Orientation = srcNode.Orientation;
}