I started working on some metrics about my render engine and i cant figure out how to count the actual number of triangles/vertexes drawn. I have the total number of mesh vertexes from the moment i load the obj model.

I found some answers but most of them were that i have to count them myself. Yes, i understand that is is not a OpenGL API call but how do i count them when i use culling or other mesh is behind the wall ?? It is obvious that i am not rendering all the mesh that i have on the screen.

Do i need to use like atomic counters to count how many times vertex shader runs.

NOTE :: I am trying to avoid OpenGL 4 until i start working with learning tessellation.

Thanks