I am starting testing of the internal use of Unity 3D lightmap. Some initial results show that the use of internal lightmap tool is very competent and powerful, but its configuration is not simple to do.
The first tests performed used to generate Occlusion Maps closed for a scenario where only one directional light was responsible for creating the shadows. During my tests, some objects simply disappeared from the scene (both in Design and during game play). I am studying the problem, which must be caused by using textures with transparency.