Hello All,
I have modeled a character which has about 4000 quads, so 8000 tris in it. There are roughly 4000 vertices in the model as well. The quads are spread across 2 materials, so as characters go, this one is not terribly complex.
Now, when I import the model into a Unity scene, there are about 22000 tris.??? Is this normal, for Unity to add so many triangles to your models? If so, what import settings can be used to, at least, minimize the number of polygons that result in Unity?
Vertices need to be split depending on normals and UVs, plus multiple lights can multiply triangle count, and using multiple materials will increase it as well.
–Eric
You need to think about it in terms of what data an individual vertex can contain, when sent to the graphics card. It can have one uv coordinate per set (and in Unity you can have two sets). So if you have a vertex on the edge between two seperate uv patches, it will have to be split (become two seperate vertices, sharing position in 3d space) in order to be on both coordinates.
And a vertex can only have one normal defined. So if you have a vertex along a hard edge, this means it has to be split into two, each with its own normal. The same goes for material Id’s.
It’s the same for all engines, as it really is the graphics cards inner workings defining these data structures of a mesh.
And all the 3D packages does the same internally (at least if they use the graphics card for rendering the viewport, and not some software rendering), but for some odd reason they doesn’t show you the actual numbers (at lest 3ds Max doesn’t), but instead a “polished” version. Beyond me.
Here are some great info about the splitting subject, plus general info about optimization: Beautiful, Yet Friendly Part 2: Maximizing Efficiency