Does anyone know how to calculate number of vertice of different shape? for example a cube suppose has 8 vertices, why do we need to mutiply it by 3 to build in Unity? The same question to a “torus”, why not just multiply “number of sides” and “number of segments” to get the vertices of torus instead of (side+1)*(segment+1) which works correctly on Unity?
It would be nice if someone can explain.
Thank you in advance.
A cube only has 8 vertices if you use the same normal for the vertices shared by 3 sides, which leads to incorrect lighting. You need to split vertices if you expect to use correct normals, since the faces of a cube are flat and need different normals on all sides. You’d also need to split vertices because of UVs. So there isn’t any specific answer, since it depends on what you’re doing with normals and UVs and whether that allows for shared vertices.
–Eric