As seen in the screenshot below, the walls for my interior (And the floor) are covered in these stretched, weird-looking shadowy streaks (Only on some walls, not all). I thought this was to do with the lightmap error I kept getting, but the building shell wasn't one of the objects it mentioned. I've been at this for around 3 days now, and have turned up nothing and therefore have come here for some guidance. What exactly causes this, and how do I improve the lighting environment using GI and baked lightmaps? Is this a UV issue?