Odd Foliage Paint Behavior with World Collision On

[anonymous_user_7e0ab2aa]

Does anyone have an idea of why this landscape is painting this way, and how to resolve it? (Details follow.)

The behavior is triggered when painting foliage on a landscape using a foliage type with “Collision with World” enabled. Notice that the boundary of the behavior always lines up with tile boundaries.

Steps used to get this behavior:

1. Create a new 4.12 project using the blueprint third person template.
2. Add “Open World Demo Collection” to the project.
3. Create a new default level and delete the floor mesh.
4. Create a new landscape. Use the default settings except change “Sections Per Component” to 2x2.
5. Create a new Foliage Type and assign HillTree_Tall_02.
6. Set the foliage brush to maximum size and density and test paint on the landscape. Coverage should be full with no unexpected behavior.
7. Undo the test paint.
8. In the Foliage Type, toggle “Collision with World” on.
9. Paint the landscape again. (I get the above behavior.)

Ideas?