mac version: VSync only double buffered/page flipped

[thedreadedgman]

I've been playing around with the settings on OS X Portal to try and get better performance, and noticed when VSync is on, you're locked to multiples of the refresh rate (60, 30, 15) etc

so that tells me that Portal's VSync implementation is only double-buffered (or page flipped)...

So I went back to my Win 7 machine, and tried Portal on there, with VSync enabled, I can see 42FPS, up to 60FPS... which tells me that Windows Portal is using triple buffering for it's VSync...

If Mac Portal was upgraded to use Triple Buffering, I think the performance would be a LOT better...

I'm just saying because I really dislike playing games with VSync disabled, screen tearing really bothers me...

Since the performance of the Source engine under OS X is fairly low so far, it only makes sense to use Triple-buffering because otherwise even if you're getting 40 or 50 FPS, you will actually only see 30 FPS...

thoughts?

[thedreadedgman]

to better illustrate my point here is a chart:

http://img517.imageshack.us/img517/2615/fpschart.png

[warren_toronto]

Well when playing on my iMac 24" aluminum, the windows performance (using bootcamp) is about four times as high as the Mac version. I had to drop to half of native resolution to be playable. Without vsync, the tearing is wicked, and with it, the frame rate seems about 20 fps when the scenes are simple and 10 fps when the scenes get complicated. The energy-globes and any lightning or particle effects drop it down. I played all the way through last night, and while I'm glad Portal (and Source) are on the Mac now, I hope that by the time they get the HL2 Mac version out, that the source engine performance is about four times the current one, or I'll have to boot into Windows just because the Source engine on Mac OS X is not nearly as good as the native Win version.

But I'm sure that something this huge is a major R&D effort. That it works (moving from DirectX to OpenGL) is a massive cool hack on the part of the Valve team, and my praises (and slack-jawed amazement) shall never cease. All hail, mighty Valve. Ye all rock, verily, and mightily.

W

[The Comfy Chair]

Originally Posted by warren_toronto

Well when playing on my iMac 24" aluminum, the windows performance (using bootcamp) is about four times as high as the Mac version. I had to drop to half of native resolution to be playable. Without vsync, the tearing is wicked, and with it, the frame rate seems about 20 fps when the scenes are simple and 10 fps when the scenes get complicated. The energy-globes and any lightning or particle effects drop it down. I played all the way through last night, and while I'm glad Portal (and Source) are on the Mac now, I hope that by the time they get the HL2 Mac version out, that the source engine performance is about four times the current one, or I'll have to boot into Windows just because the Source engine on Mac OS X is not nearly as good as the native Win version.

But I'm sure that something this huge is a major R&D effort. That it works (moving from DirectX to OpenGL) is a massive cool hack on the part of the Valve team, and my praises (and slack-jawed amazement) shall never cease. All hail, mighty Valve. Ye all rock, verily, and mightily.

W

Indeed, i do feel that source has never been particularly happy on OpenGL (the performance on the ps3 version of portal was fairly dismal), so i'm hoping that they get it more and more optimised

However due to some features on mac that never get locked out from the GPU like on windows (like the 'desktop') you'll always need more gpu oomph to run the game on mac still, no reason to get 25% of the performance though.

Hopefully by the time left 4 dead: mac comes out it'll all be sorted and you can join us all in the zombie slaughter fest ^^

[Timerider42]

I've noticed rather low framerates as well, compared to running Win7 on the same MacBook Pro.

[thedreadedgman]

Originally Posted by warren_toronto

... Without vsync, the tearing is wicked, and with it, the frame rate seems about 20 fps when the scenes are simple and 10 fps when the scenes get complicated...

So by this standard your monitor refresh rate would be 40hz or 80hz... Usually LCD screens are 60hz...
On the Late 2009 iMac (C2D 3.06Ghz 21.5in screen, ATI HD 4670) it is 60hz by default...

remember you can see frame rate:

1. Options > Keyboard > Advanced...
2. Tick box: Enable developer console
3. You can now open the console using the ` (backtick) key next to 1
4. From the console enter: cl_showfps 1
5. Your frames per second will be shown at top right of screen

[MDA400]

Its a shame most affordable macs dont contain Nvidia chips. if you have a standalone mac or a mac pro with an nvidia (say with a GTX 285 for mac), you can force triple buffering for OpenGL applications in the Nvidia control panel (not sure if mac has one but it should).

[thedreadedgman]

Originally Posted by MDA400

Its a shame most affordable macs dont contain Nvidia chips. if you have a standalone mac or a mac pro with an nvidia (say with a GTX 285 for mac), you can force triple buffering for OpenGL applications in the Nvidia control panel (not sure if mac has one but it should).

Mac has.. "limited" options

In fact, if you want to tweak it, probably not the best platform for it... although perhaps there is a force-triple-buffer options somewhere in the config files...