Celestia Forums

I'm not too sure wether this is better posted in the Users forum or the Bugs forum. I'm guesing that since I haven't heard anyone else mention this, it may not be a bug, and just a problem with my setup.

When I am either running time faster than realtime, or am moving from one object to another in the solar system, the display seems to "surge." It will alternately run at a fairly fast rate, then slow down noticably with a period af about 1 second or so. It's not a huge problem, but is very distracting, especially when showing the various flybys that Cassini is going to make, etc.

If anyone has a solution to this, I'd really apprecaite it. I've been using Celestia for over two years now, and haven't seen anything like this before. I have recently acquired a new laptop, and it is this machine that I'm having the problem with.

Running Celestia 1.3.2pre8
Pentium 4HT - 3.02GHz
1 Gb RAM
NVidia GeForce FX Go5200 w/ 64 Mb RAM
Win XP Home
Displayed at full screen (1024x768)

I have run 1.3.2pre7 on my desktop with no problems (1GHz P3, 512 Mb RAM with a NVidia w/ 32 Mb RAM... Win2K PRO). It is surrently in storage after a move, so I am unable to do a direct comparison with pre8 on it for a little while.

Any thoughts or ideas would be appreciated.

Thanks,

Gil

Gil,

Could be just a problem with the laptop. I haven't seen anything like that on my
desktop, and it's just a Gateway.

Take care, Bob

Many new laptops change their clock rates depending on how hard they're being used.

3D graphics chips generate a lot more heat when they're used to generate moving 3D graphics. Could it be that yours has an automatic clock-rate adjustment that slows it down when it gets too hot?

Selden,

It may be, but I'm not so sure. If the computer has been off for a while and I start up Celestia just after starting the computer, I see this happen.

If this is the case, does anyone know a way to force the clock rate on the card to a slightly slower rate so this doesn't happen?

As an additional note (which I said in the subject, but didn't in the message), I'm only noticing this when in our solar system. If I go to an extrasolar planet and turn up the pace to see planets orbiting, or move from star to star, etc. I do not see this effect. It's only "at home" so to speak.

I don't know why, but could the computer by trying to do too much? I even tried running with just normal resolution textures (turning off the virtual textures I have). I do have the additional newly discovered moons of the outer planets installed, but no asteroids, etc. so I am at a loss. It does seem that as soon as the number of objects that it has to deal with (as in an extrasolar system) things run just fine....

Again, any insight anyone can provide would be appreciated.

Thanks,

Gil

Check the filetypes, if you got any PNG files for only 'our' system, than try without them...PNG's are the killer on my setup...

Thanks to all who helped out with this one. I finally have it solved. I updated the NVidia drivers (especially OpenGL) and that took care of the problem.

The moral of this story is even though you have a brand new (3 weeks old) computer, never, ever trust that the latest drivers have been installed!!

Happily simulating away,

Gil