When the Umbra plugin is loaded and Umbra data for the level exists, the renderer will by default use Umbra culling in all viewports both in editor and game views.
The following console commands are available for adjusting Umbra operation:
|r.UseUmbraCulling (0/1)||Toggles Umbra culling on and off.|
|r.UmbraParallelVisibilityTasks (1-64)||(Dev) Number of async tasks to launch for each query.|
|r.UmbraAccurateOcclusionDistance (world distance)||(Dev) Query time vs quality scale.|
Statistics for Umbra culling can be viewed in the stats category "UmbraCulling":
Umbra and occlusion queries
Umbra and UE4 occlusion queries can be enabled independently. When both are enabled, Umbra reduces the amount of occlusion queries and latent culling artifacts, improving handling of larger areas and big object counts, and also levels out spikes in frame time. Umbra visibility query is executed parallely and ideally introduces no latency for game or render thread.