When using Trace Complex in a LineTraceByChannel node does not give accurate results when object is simulating physics and scaled. The scaled root mesh in the BP will only register its collision rather than detecting any object inside it.

Sample Project attached: 4.8 - CL-2521032

Steps to Reproduce

1. Open UE4
2. Create a BP with two static mesh assets
3. Make the root an asset that is hollowed out and a missing front. (ie. a box that is hollowed with missing or tire-well on a car, like the users AH link)
4. Second mesh can be anything inside the first mesh
5. Setup the player character to do a line trace by channel (see attached Image for BP setup)
6. Place BP with two meshes in the scene
7. Set up the Level BP to simulate physics for the two meshes in the BP on key press
8. PIE
9. Move the line trace between the mesh 1 and mesh 2. You should see them both registered
10. Press key that simulates physics
11. Move the line trace between the two meshes again. Should only register the root mesh so long as the collision is larger than the interior mesh.

1. Open Sample project attached
2. PIE
3. Move line over the sphere and the box. You will see two different meshes registered
4. Press G to simulate physics
5. Move the line trace over the box and the sphere. You should only see collision for the box and no longer detecting the sphere.

Results: When the BP is simulating physics on the objects Trace Complex no longer seems to look beyond the collision of the box and at the geometry.

Expected: When simulating physics and using trace complex the mesh geometry should be used like when not simulating physics.

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ComponentUE - Gameplay
Affects Versions4.7
Target Fix4.9
Fix Commit2565625
CreatedApr 27, 2015
ResolvedMay 26, 2015
UpdatedApr 27, 2018