Vsync problem with OpenGL in linux ubuntu

[mrAlmond]

Hi all,

This is my first post in here.
I'm trying to develop a simple application in linux ubuntu using Irrlicht and OpenGL.
My video card is an ATI express 1250.

The major problem for now is a strange flickering/stuttering effect that appears more or less each second. I think that it could be a Vsync problem.
I've tried to activate the Vsync from the ATI catalyst control center (set to "quality", always on), but the bad effect seems to be even more evident.

In irrlicht I've also enabled param.Vsync = true; in createDeviceEx like this:

Code: Select all

irr::SIrrlichtCreationParameters param;

param.DriverType = video::EDT_OPENGL;
param.Fullscreen = true;
param.WindowSize = core::dimension2d<s32>(1024, 768);
param.EventReceiver = &receiver;
param.AntiAlias = true;
param.Bits = 32;
param.Stencilbuffer = true;
param.Vsync = true;

device = createDeviceEx(param);

but unfortunately nothing changes...

Is there a way to fix this issue?

I've also an antialiasing problem...as you can see I've enable it but I keep on seeing 3d cubes edges not smoothed as they must be.

Thank you in advance.

Gianluca

[hybrid]

OpenGL under Windows still has no anti-aliasing, I did not know of any problems under Linux.
VSync should also work, but there had been some driver problems once. Maybe you should try and update your driver and see if this fixes some problems.
Or do you have some frame-rate dependent code or something like that? Is it in the SDK examples, too?

[randomMesh]

ATI, Ubuntu, stuttering... That reminds me of this.

Maybe it helps.

[mrAlmond]

Thank you for your answers...I'll try to update my drivers (but I'm quite sure that I'm using the latest version) and I'll try also to modify my xorg.conf...
I'm not using frame-rate dependent code...

I'll let you know if something is solved...

[mrAlmond]

I've tried to change the xorg configuration but nothing changes...
The same problem is visible using glxgears...but if I use fgl_glxgears everything runs smooth...

[CuteAlien]

I remember that vsync didn't work on linux for me once. Long time ago - so no longer 100% sure how I fixed that. I think it worked after I changed the linuxdevice so that it checks for randr before vidmode. For a quick test if that might be the reason you can change the defaultmode in IrrCompileConfig.h by disabling _IRR_LINUX_X11_VIDMODE_ and enabling _IRR_LINUX_X11_RANDR_ instead.

[mrAlmond]

I've tried also that mod but nothing changes...
However thank you.
The strange thing is that glxgears has the same problem but fgl_glxgears runs smooth...I've tried also the glexcess demo (not using irrlicht) and it also runs smooth....so I think it's only a software issue...I must find the right settings...