Low framerate with 3d mouse

[Nebur98]

Hi,

I noticed that when I change the view with the space navigator the movement appeared somehow jerky.

Further investigation using a software that shows the framerate of DirectX/OpenGL viewports (FRAPS) shows that when rotating/panning with the normal mouse I get exactly the desired 60fps (v-sync!).

In contrast when I move around with the space navigator nx delivers exactly 40fps instead of the expected 60fps!

I performed the tests with parts that surpass 100fps with disabled v-sync, so the GPU horsepower to display the 60fps is easily available.

Made the same test with MastercamX on the same machine/config and there I get 60fps regardless of using the space navigator or the mouse to move/pan, so it must be related to Nx somehow.

Anybody out there with a solution or a similar problem? I know its not a major problem but I would really love to get a smooth movement in sync with the screen refresh rate. It looks like a stepwise movement instead of a flowing motion and I'm used to move the parts around continously when working so it really hurts my eyes.

This is my config:
- Core2Duo 2,4Ghz (cpu throttling intentionally disabled to avoid timing problems in applications that expect a constant clock)
- Quadro Fx3700 with v-sync on
- Win XP 32
- NX7 with MP2(of course 32bit version)
- Space Navigator with latest driver and NX plugin installed (removing the nx plugin did not change anything)

I would appretiate any help.

Cheers,
Nebur

 

[JohnRBaker]

Did you check to see if the 'Fixed Frame Rate' option was set on the...

Preferences -> Visualization Performance...

...dialog. Try unsetting it and see if this helps (I don't know that it will, but it's one of the few things that I can think of that might). Since you seem to be implying that this only appears to be a problem when using the SpaceNavigator, you may also wish to open the 3Dconnexion Control Panel, go to the Advanced Settings tab and max-out the Speed settings on all of the Individual Axes.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.

 

[Nebur98]

Thank you John. Unfortunately I already played with the options you mentioned without any success.
It's weird, the framerate is spot-on and without any variation 40fps when moving the 3d mouse and 60fps using the normal mouse.

I thought that it could be an algorithm inside nx that the polls the 3d mouse movement based on QueryPerformanceCounter() and does not take into account that the cpu clock may change dynamically.

My machine would normally throttle down from 2,4Ghz to 1,6Ghz when idle. That's exactly the same reduction ratio (40/60fps = 2,4/1,6GHz = 2/3) I see on the framerate. So I was pretty sure that disabling the cpu throttling in the BIOS would help but it does not. I verified the CPU clock with a monitoring software and it really stays on 2.4Ghz, still the problem persists. I'm really out of ideas....

Nebur

 

[JohnRBaker]

NX doesn't really do anything special with respect to the 3Dconnexion software as we just leverage whatever the combined graphics hardware/firmware configuration on your system is capable of doing. So if there's an apparent performance issue with the SpaceNavigator it's more likely something to do with their software or how it interfaces with the graphics hardware/firmware than anything NX is doing.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.

 

[Nebur98]

The space navigator and it's driver/software do not interface with the graphics hardware. NX is always in between and applies the motion to the viewport. The big question is why it results in exactly 40 updates per second. Either the 3DConnexion driver does not respond faster (unlikely considering that it works in other applications without limitations and that the framrate is always precisely 40fps in NX) or NX does not accept more than 40 updates/s to the "camera position" (also very unlikely considering that with v-sync off and rotating the part wildly with the 2d mouse NX delivers more than 300fps(!).

Whatever, I was hoping for a special UGII_xyz env variable that would resolve the problem but it seems to be more difficult.

Thanks for your help anyways!

Cheers,
Nebur

 

[Nebur98]

The problem is kind of solved so I thought it could be of use to other to know what was going on:

It is a problem with standby/hibernating of the machine. If the computer was once in one of these power saving modes since the last regular boot the problem happens. Stanby+Resume and the frame rate drops to 40, reboot and it is again 60fps. Strange but at least knowing the workaround it's avoidable.

Cheers,
Nebur