A Simulating Physics component with StartAwake = false will be awoken by a Welded component

UE - Simulation - Physics - Jan 10, 2025

A Simulating Physics component with StartAwake = false will be awoken by a Welded component If a welding occurs during the call to OnCreatePhysicsState, this breaks the start awake disabled flag. Th ...

Unnatural de-overlap occurs when moving inside a mesh-type collision located far from the origin

UE - Simulation - Physics - Jan 8, 2025

The problem appears to occur when the distance from an edge is mixed with positive and negative values in VectorEPA function. The following workaround is suggested that uses absolute values of dista ...

Enabling "ShowFlag.PhysicalMaterialMasks" causes editor crash when physical material masks aren't yet imported.

UE - Simulation - Physics - Dec 3, 2024

When there is a physical material mask asset that has been created and applied to a mesh in the level without having a texture source imported yet, and then "ShowFlag.PhysicalMaterialMasks" is enabl ...

The ChaosCacheManager changes the bSimulatePhysics flag from the ObservedComponents and, if deleted, the change will persist, what can lead to confusion as observed physical entities will inadvertently stop simulating physics

UE - Simulation - Physics - Nov 26, 2024

The ChaosCacheManager (CCM) changes the bSimulatePhysics flag from the ObservedComponents and, if deleted, the change will persist, what can lead to confusion as observed physical entities will inad ...

A welded hierarchy blocks updates to collision settings on all but the root primitive. Calling SetCollisionResponseToChannel on the children won't work.

UE - Simulation - Physics - Nov 22, 2024

A welded hierarchy blocks updates to collision settings on all but the root primitive. Calling SetCollisionResponseToChannel on the children won't work. The licensee noticed that IPhysicsProxyBase* ...

Changing the state of a PrimitiveComponent->BodyInstance while SetSimulatePhysics(false) updates the game thread but does not update the physics behavior

UE - Simulation - Physics - Nov 21, 2024

Changing the state of a PrimitiveComponent->BodyInstance while SetSimulatePhysics(false) updates the game thread but does not update the physics behavior. In the repro project provided (see addl in ...

CharacterMovement doesn't clear velocity

UE - Simulation - Physics - Oct 11, 2024

Velocities are not being cleared when physics simulation set to false.  ...

Physics Linear Velocity functions from UPrimitiveComponent always return (0,0,0) velocity

UE - Simulation - Physics - Jul 30, 2024

In Unreal Engine version 5.4, all Physics Linear Velocity functions inside PrimitiveComponent class are returning always a velocity of (0,0,0), even if the Body Instances are moving. This was workin ...

Geometry Collections don't support any collision visualization modes (Collision, CollisionVisibility or CollisionPawn)

UE - Simulation - Physics - Jun 27, 2024

Geometry collection objects do not display any collision visualization, either collision color or wireframe overlay when the view mode is set to Player Collision or Collision Visibility or when the ...

Get Velocity nodes with a specified bone return incorrect values

UE - Simulation - Physics - Jun 10, 2024

Please note that a similar issue exists [Link Removed], however it is not the same, as this issue requires a bone to be specified in the node to occur. Leaving the Bone Name field as None or Root pr ...