One new side effect we have noticed is errors in foliage lighting what were not present in 4.4
The foliage in the screenshots were lighting properly before we upgraded. Now you can see some strange bright clumps of foliage and some black. Level lighting setup has not changed.
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Thank you.
There have been several adjustments to how lighting works with foliage in 4.6, specifically:
"Static Lighting on Foliage
Precomputed lighting and shadows are now supported on foliage objects and instanced meshes! This allows for very efficient rendering in scenes with Stationary or Static lights.
This Image Was Automatically Resized by using the Screenshot Tag. Click to view the full version
Static lighting is appropriate for medium sized levels but does not scale up to huge scenes in build times or memory requirements. Be sure to use very small lightmap resolutions on meshes that will be instanced many times.
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You can find more information on changes made to the editor here: