Fantastic that viewer. The quality of the render is very good.
What's the size of the textures you are using, and also, how much "customized" each texture map is to each part of the model: do you create a map specificaly for a certain piece or you have a "general wall" texture that you apply to everything?
What's the size of the textures you are using, and also, how much "customized" each texture map is to each part of the model: do you create a map specificaly for a certain piece or you have a "general wall" texture that you apply to everything?