Why PSM port is so slow ?

Hi !

I recently did some tests with the PSM port of monogame and everything is working fine (including my engine and my game). The problem is it’s extremly slow ! Monogame seems to start lagging after 400 draw calls. Sony Spritebatch demo supports 4096 sprites without even a frame drop. I don’t understand why monogame is so laggy. I want to help but if someone can explain me what is actually wrong, it would be helpful.

I suspect it has to do with the rather dumb combined vertex and index buffer type within the PSM API. This causes a proper API like in XNA or MonoGame to jump thru extra hoops to make it seem like vertex buffers and index buffers are interchangeable. See…


The PSM demos don’t have to jump thru these hoops.

It is telling that this is the only platform where we have this problem.