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Using double buffer and the buffer swap function to end the draw loop, SDL_GL_SwapWindow, when I set the Vsync to Off through: 

SDL_GL_SetSwapInterval(0); //returns 0 so the vsync option is set correctly

Looks like the VSync is still on on this device.

I've tested the same code in iOS, other android devices including tablets, pcs and mac with a very simple scene and all of them go from about 60 fps with VSync to +400 without it.

The only device that seems to keep the VSync is the Note 4 because the fps are the same.

This is why I'm asking if there any reason for this. I've looked for the device specifications and checked the display and developer options in case there was some kind of VSync locked option there but I found nothing related to this.

EDIT: Same behaviour with a Samsung Galaxy S4 (VSync won't turn off)

genpfault
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  • VSync is outside of OpenGL specification. It's device vendor's decision whether to provide an way to control it or not (i.e. you can't assume that it will be available everywhere). I'd check with SDL developers since you are using their library. – n0rd Sep 02 '15 at 17:27
  • It's the window system that does this. It's also interesting to note that some drivers (on desktop systems) these days are implementing framerate limiting in multiple layers. On Windows, if you turn VSYNC completely off you may still be limited by driver settings to 60 FPS (AMD and NV call this a "target framerate" in their latest drivers), this saves electricity and lets the cards run cooler and quieter. That is a poweruser setting though, AMD/NV GPUs don't come configured that way out of the box - but I am using it to illustrate that framerate limitation is not necessarily due to VSYNC. – Andon M. Coleman Sep 02 '15 at 17:37

1 Answers1

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As clarified in comments and documentation, there are drivers and hardware setups that limit the framerate regardless of the vsync configuration/framerate specific management.

In particular, the framerate is limited in most new Android devices.

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