When using precomputed visibility on device for occlusion culling the landscape does not take the cameras view into account for culling objects when out of view of the camera and inside a visibility cell. Checking this against how Static Meshes work the static meshes behind will be culled.
Using the freezerendering cvar can demonstrate this like the images below.
1. Open UE4
2. Enable Precomputed Visibility in the World Settings
3. Add a landscape to the scene and make a large mound for occlusion
4. Place a large lightmass importance volume and Precomputed Visibility volume around the area.
5. Place some cubes behind the landscape mound.
6. use the build button in the Toolbar to build the vis cells and lighting
7. launch on mobile device (in editor still uses dynamic occlusion culling to cull objects)
results: The landscape does not cull objects when using precomputed visibility on mobile. It will only cull if another static mesh is blocking the view of the other static meshes.
expected: the landscape should help cull objects when using precomputed visibility, much like it does with the static meshes blocking other static meshes based on the camera view in the visibility cells
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