UV mapping adding vertices?

Does anyone know why UV mapping something makes it take up way more vertices? Because I have a model that when not UV mapped is just under 300 vertices, but when UV mapped it's like 450. Is there any way to UV map without getting the extra vertices added? Because under 300 will batch while my new ones wont batch. Is there any way around this? or anyway to add a texture without UV mapping? Thanks.

 

No one?

 

Could be any number of things. Say your base mesh has 200 vertices. Add two pixel lights to your scene and those have to be rendered two more times, suddenly you have 600, each light that casts shadows does the same, and then any smoothing groups you have on your model, the vertices at the edges are doubled at the seams. Same with multiple materials on a mesh. The verts at the seams of the materials are doubled up too.

So you can easily end up with more than 1000 verts being rendered in Unity whilst your original mesh in your modeling tool only showed 200. Your modeling tool only counts the verts you manipulate on the modeler, not the result of all the combined render passes.

 

Yeah but it's in the exact same scene as the first model was in, the only difference is that one is UV mapped and one isn't.

 

Two differnt UV set (same mesh) does not give the same "Vert" count. Detach a tri in the UV and you get 2 extra verts.
Usually this does not show in the vert amount in your 3D application.

 

So, is there a way to add textures to an object without UV mapping the object? or is there a way to UV map it without adding all the extra vertices? Otherwise I may have to go with just a plain material (which I would prefer not to).

 

It's impossible have textures without UV mapping. If you map the object in such a way as to minimize UV seams, then it won't add as many vertices.

--Eric

 

What if I didn't add any UV seams?

 

UV seams are basically the outside edges of the shapes that are laid flat in the UV editor. (Highlighted green) Not the visual representation of seams used for pelt mapping etc which are cyan/blue.