Do I need to split my mesh up to properly UV texture it?

[cobertos]

I’m procedurally generating meshes for my game and I have a few questions.

Say I have a cylinder with a top, bottom, and sides. I need to assign different UV values to the vertices shared by the top and sides. Does splitting up these vertices, so that there may be two in the same place, have any noticeable impact on performance or resource usage? Is there a better way to do this? Is this standard across all engines (do most game engines want you to split up your vertices like this)?

In addition to the questions above, do I need to split up my mesh into multiple mesh’s (multiple mesh filters) to apply multiple materials to it? Can I keep the one mesh together and texture different triangles differently?

[Benproductions1]

To answer your first question: The only reason gameEngines split up some, but not other vertices, is because of Normal Interpolation. If the vertices were combined, it would result in every edge being smoothed. When this is not a desired effect, the vertices are split. Unless your working in the millions, there is no noticeable difference.

For the second Question: You need to split up your mesh into submeshes in order to apply different materials to different parts. You can’t have more than 1 Mesh Renderer on one object

Hope this helps Benproductions1