[jo_]

I remember being surprised that the bottleneck for some modern devices (like cell phones) wasn't the number of vertices one could push, but rather the fill rate and number of draw calls. Do consoles these days hit performance bounds as a function of the number of draw calls rather than the number of polygons/vertices?

I ask because I can completely understand how doubling the number of draw calls could be problematic in a VR situation.

[modeless]

Mobile devices are often limited by memory bandwidth, and by OpenGL driver overhead. Consoles have very little driver overhead, so number of draw calls is not as big a problem, but state changes are still costly, so doubling the number of state changes hurts performance. I could imagine some clever techniques to avoid doubling the number of state changes (perhaps a geometry shader that duplicates triangles to render both eyes at once) but I don't know how well that would work. VR rendering is still mostly unexplored!