Ogre Forums

I know this maybe has nothing to do with ogre (that's why I post here). It is somewhat funny actually.

When rendering very simple scenes, even some of the ogre samples, the window gets extremely choppy meaning the image gets updated very irregularly, looks like it's stuck, but fps are actually very high, around 2500 in my case. OIS input get choppy too. Anyway it's not a big deal cause everything returns to normal when fps lower to reasonable velocities. It also disappears when turning vsync on.

This happens on Ubuntu 11 with an Nvidia geforce 275 gtx and of course the latest official Nvidia drivers (275.21) which by the way is the only driver that can make my autodesk maya work.

Just sharing...

yeah this is what vsync is for to slow down the rendering

Dont worry : it is the same on windows . This is why I turn vsync when not in fullscreen mode for my tutorials. What is more, everybody gets the same framerate that way.

also there is no reason to go above the monitors refresh rate as you never see the frames anyway

Hi, there's no reason to render faster than the monitor's refresh rate. You're just burning cycles and wasting more power and heat.
Also read this and make sure you understand it.

The reason it gets choppy is because at single precision floating point, 1/2500 = 0.0004. With almost everything being multiplied by 0.0004; some floating point inaccuracies (specially those that accumulate from frame to frame) may start to show up. Insane high framerate can cause this, make sure you provide a framerate cap. At some point theoretically it might be so high that timeSinceLast gets rounded to 0; therefore nothing advances.

And seriously, read it. I mean read it. Don't forget to read it! It will save you a lot of headaches.

Cheers
Dark Sylinc

PS: Another reason (very unlikely) might be that there's an OS bug or HW fault that shows up when 100% resources are being used. Very unlikely.

Hear, hear

dark_sylinc wrote:Hi, there's no reason to render faster than the monitor's refresh rate. You're just burning cycles and wasting more power and heat.

Well yeah, that is reasonable. I want to be green on release! Lol. But when developing I like to keep the track of my fps. I end up writing down how much I gain or loose when adding new assets, shaders, logic code, etc. It makes me very aware of any bottleneck. For instance, just recently I discovered how extremely beneficial it was to use gpu skeletal animations. Or maybe using an expensive shader isn't that hurtful after all. I have learned a lot just by looking at my fps