Can anyone tell me what may i be doing wrong here. I never had this kind of problem but now i cant seem to find a workaround past this. When i create a lightmap everything is fine. But after i make a build of a project the lightmap gets weird artifacts. Also after making a build the editor version looks ugly too. Only way to get a good lightmaps back is to bake another set of maps. But there is no point because the artifacts will come back after i create another build.
I added a before and after pictures to illustrate my problem.
The degradation in quality is compression artifacts when built. To see the artifacts in the editor make sure “Compress Textures When Importing” is checked in the Preferences. If you don’t want any artifacts on solid color surfaces like your white wall there it might be necessary to set the lightmaps to “True Color” to avoid DXT compression artifacts. This of course has disadvantages of larger file sizes and memory consumption.
I think you should find a way to keep the compression though. It will allow you to use higher res lightmaps without using a lot of ram. More noisy texturing in general can hide the artifats pretty well, although if you are going for the clean arch viz style then I guess you have to use uncompressed.
