3D Model for Game Question. Does more UV shells affect performance?
I'm new to to game dev and creating game assets. Just wanna ask.. if all the faces in UV map is cut (1 face = 1 shell), will it affect the performance? Just wondering since if that does not affect anything then I guess I won't be meticulously sew everything.
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it would mean that a 10,000 face model would have 30,000 verts in game where an "efficient" model could be a low as 5000, so that's "in theory" 1/6th the time to transform in the gpu (though 6 times very little is still very little) it would be considered bad practice.
The real question is what is your texturing going to be. Like you might not even need to flatten everything all that intelligently if you are packing UVs into some swatches and gradients for some stylized looks.
If you are intending to do stuff like bake normal maps from a high poly character sculpt, you'll just have a bad time if you don't spend 10mins UVing.
Splitting all UV faces won't even work well for using tiling textures and trims in environment art most of the time. At least smooth the mesh to 45-60 degree and press the button that flattens the UV based on those edges. It'll take the same anount of time as pressing break and then flattening.
^^^ all that, plus, the more shells you have, the blurrier your textures will be.
You need empty space between shells for "padding" which helps avoid color bleed.
The more shells there are, the more pixels have to be used by padding, and the less pixels will be available inside the shells.
More about that here http://wiki.polycount.com/wiki/Edge_padding