I have made a building that I will use in my unity video game. The building has a door way that is open yo you can get inside and all no windows so you can get inside through the windows too. The building I four stories tall and each story has 3 rooms and one hallway. So basically what I’m trying to say is it’s not just a rectangle sticking up out of the ground so I can’t just slap a side of a building texture on it 
so I want to use a uv map but when I make a map 3000 by 3000 it is still looks very pixelated in the game. But if I use a map with 10000 by 10000 it slows down my computer really badly when I try to paint it but I don’t see any pixles. If there is no way to make the pixels unoticeable without the lag I guess I will just need to deal with it. But my models are not professional so I wanted to make up form hat with good texture quality and not pixles. thank you for reading and if you have any solutions please share them 