Shaded view. Notice dark artifacts around the objects' edges caused by the UV overlaps. UV Overlap debug view. Notice the lack of overlaps in the image on the right. Overview This feature was developed by Rasmus Rønn Nielsen (@rasmusn). In the Mesh Importer users have the ability to automatically generate lightmap UVs. Traditionally, we had a setting called Pack Margin. One could use this setting to deal with texel bleeding across lightmap islands. However, for various reasons this setting is extremely difficult to use and is generally disliked. This feature introduces a new way to work with lightmap UV margins. The new method allows the user to set Min Lightmap Resolution and Min Object Scale. These can be thought of as "a contract". As long as the imported model is used in scenes that has a lightmap resolution of at least [Min Lightmap Resolution] and as long as instantiations of the object is scaled to at least [Min Object Scale], then Unity will guarantee no bleeding across islands. This is achieved by conservatively calculating a pack margin that is large enough to avoid leaks. Unfortunately, larger margins can of course also cause lower texture utilization. There's no free lunch, but at least we now get correctness. Setup instructions New pack margin options are available in the Mesh Importer window. Select your mesh, and make sure that Generate Lightmap UVs flag is enabled. Unfold Lightmap UVs settings, and set the Margin Method to Calculate to access the feature: Feature access & feedback You can get access to the feature by downloading the latest 2020.1 alpha build via the Unity Hub, or via this link. We are looking forward to hearing your feedback!