The foliage instanced mesh, as well as ISM and HISM components both appears to be unable to export navmesh data for generation once we introduce a change in the contents. This error only shows up in a packaged game,

This was reported and tested in 4.22.2 (CL-6574378) and reproduced in 4.23 (CL-6836100)

Steps to Reproduce

You will need a Source Build of the Engine for this issue

  1. Download and open the attached project in a Source Build
  2. Setup a custom Project Launcher profile based off the attached screenshot
  3. Launch the Custom Profile
  4. Open the project in Windows Explorer and run "start_server_client.bat"
  5. Press any key when prompted

Results: Once you introduce a change (eg Update Transform) in the instanced mesh tree the navmesh will ignore the instanced meshes, so the AI will not be able to navigate properly in these areas.

Expected: The navmesh will be properly regenerated around the ISM (foliage) exactly as it is happening in the Editor.

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Won't Fix
ComponentUE - AI
Affects Versions4.
CreatedJun 6, 2019
ResolvedAug 27, 2021
UpdatedAug 27, 2021