4.6.1 Actor positioning doesn't work if base actor use async scene


Actor positioning doesn’t work if base actor use async scene, repro steps:

  1. Create a sample fps project in 4.6.1
  2. Put somewhere on scene two StaticMesh’/Game/StarterContent/Shapes/Shape_Cube.Shape_Cube’ for example
  3. On the first cube turn on “Simulate Physics” and turn off “Start Awake” options from Physics section of actor properties, then mark Use Async scene
  4. Try drop from content browser another static mesh StaticMesh’/Game/StarterContent/Props/SM_Bush.SM_Bush’ for example on the first and second cube
  5. Observe the issue

I think the problem is here:

FActorPositionTraceResult FActorPositioning::TraceWorldForPosition(const UWorld& InWorld, const FSceneView& InSceneView, const FVector& RayStart, const FVector& RayEnd, const TArray<AActor*>* IgnoreActors)

FCollisionQueryParams Param(TEXT("DragDropTrace"), true);

Param should have set bTraceAsyncScene = true;


Hey -

I followed the repro steps as you described (create 2 cubes, change settings, create 2 bushes) and both bushes were placed on top of the cubes. Could you provide a screenshot to help me understand what you’re seeing if this is not the same behavior happening on your end.


Hi ,
thanks for fast response:)


as you see the bushes is inside the cube.


The bush is at the top of the cube.

This is happening when You dragging something from content browser to scene.


Hey -

I was still unable to get a mesh to end up inside the cube when dragging it from the content browser, however I did notice that when the “End” key is pressed it does not place the bush on top of the cube as expected and I have submitted this report for further investigation (UE-7153).