Ok, so lets say that i have a complex mesh, like a house. I have dragged it into unity and i can now see it. How do i apply texture for diffrent things. The walls will be white, the beems will be wooden and so on. The model is one object and if i apply the wall texture, will it colour the whole house like the wall texture? or how do i do it so it only applies to the part you want? Any ideas? Do i have to do something in blender? And how should i save it in blender?
Or is it easier just to make all parts as separate models and apply their texture to them and then build the house togheter in unity?
What you need to do is make your house in separate objects in Blender (select parts you want with one texture and press ctrl+P).
After that export house in any format you want.
Import your house in Unity and you should have multiple house parts as childs of imported object. Then just drag and drop materials on those objects.
Or you can texture whole house in Blender.
P.S. sorry if i complicated it too much.
It is possible to add several materials to the same mesh in Blender and assign the list of materials in Unity. Whenever the mesh is rendered in Unity it will always render all the materials so it is better to have one material per mesh to preserve draw-calls whenever possible.