As Belido say GG does not support specular/normal in multi-texture model, just _D file, so if you have multi-texture house:
roof_D.dds
walls_D.dds
floor_D.dds
frame_windows_D.dds
frame_door_D.dds
winglass_D.dds
and so on.
I know unwrapp coming quite handy for the perfomance, (at least while it being a mandatory), but I can get many nice efects with just uvmapping, than I can't with unwrapp.
Wonder myself if GG can work multi-textures like texture sheet does, I'm thinking now about 2x2 or 4x4 texture sheet, like Bond1 does with their tv, a sheet containing ie the above dds maps, but into one texture sheet, so the firts row being "roof_D.dds", second row being "walls_D.dds", and so on, so engine knows than it has to apply to my roof the texture sitting in the col1-row1, and so on; so GG work with just one texture like it want, and artist work with more possibilities, and less "unwrapp bothering", and less time to make model. Just my crazzy thoughts.
3com
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