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DarthPsymon
10-30-2010, 04:05 PM
Anyone else getting large drops in frame rate when a larger amount of particle effects are on screen?

Example level, 3-12. all the ice stuff just above spawn combined with the grav flip effect cause brief periods of very low frame rate.

Changing graphics to low made no improvement.

FWIW:
WinXP
AMD X2 2.2GHz
2GB RAM
GTX 260

Ok never mind, I found out what the problem was. Windowed mode.
Changing to full screen fixed it.

Turns out in the low frame rate, the clock continued at normal time, so I was getting much slower times than I should have, making the time achievement on level 3-12 almost impossible.

DJ Cryotek
10-30-2010, 09:07 PM
My netbook can run it, but it is very slow... not low fps so much as it is literally in slow motion. Wish there were more graphics setting available, if I could turn off trails or dynamic lights or something it would probably make a difference.

(I have an HP Mini with Nvidia Ion graphics (good) and Atom processor (slow. bottleneck.).

Sairon
10-31-2010, 06:19 AM
Yeah, the speed of the game depends on the frame rate. The reason for this is otherwise the physics will behave differently across machines, giving certain setups a clear advantage. As it is now one needs 60 FPS, but it doesn't go any higher. I'll see if we can't get it to go a bit faster, as you say the particle effects is a large culprit.

Lazareth
10-31-2010, 04:35 PM
Am I hearing it right that the game clock follows real-time and is unaffected by lagging?

In a game where miliseconds really does count for something, wouldn't it be better to let the time be fixed to the physics ie unaffected by lag?

Edit: of course, tampering so that you essentially play in slow-motion could be an issue...

Sairon
11-01-2010, 05:31 AM
Am I hearing it right that the game clock follows real-time and is unaffected by lagging?

In a game where miliseconds really does count for something, wouldn't it be better to let the time be fixed to the physics ie unaffected by lag?

Edit: of course, tampering so that you essentially play in slow-motion could be an issue...

Yupp, that is the reason. Basically there's 3 different solutions, none that satisfy everyone. The first is to use what's commonly referred to stepping with delta time. This means that between every frame the game calculates how long time has passed, and then use that to calculate new positions, velocities etc. This has the problem that physics vary a lot between different frame rates. In some games, for example Quake 3, it became known that certain frame rates had advantages due to this.

The other way is the way you mentioned, which gives and advantage to slow machines.

The last is how it is now, where you pretty much must have 60 FPS to compete for highscores, but if you do have 60 FPS it's an even playing field.

Lazareth
11-01-2010, 05:36 AM
Is there a way to get the game to show the framerate?

Sairon
11-01-2010, 05:52 AM
There's a trick, if you go to steam/steamapps/common/nimbus/data/GUI/layouts/FPS.layout there's a line that says:
<Property Name="Visible" Value="False" />
Change it to:
<Property Name="Visible" Value="True" />

And you should be getting a FPS meter.

Lazareth
11-01-2010, 05:56 AM
Awesome! Thanks!

Quick question again - doesn't steam deactivate achievements if you fool around with the settings by hand?

Sairon
11-01-2010, 06:03 AM
To be honest I don't know, I don't think so because we're writing log files to the game directories, which steam doesn't seem to be complaining about. Also, when we play at the office we play with custom in development builds, and we still got achievements on the steam accounts we use while developing. I can't guarantee anything though.

Saijin_Naib
11-01-2010, 10:34 AM
Sairon, what about using a fixed tic rate like used in IDTECH 4 engines?

DarthPsymon
11-01-2010, 10:37 AM
There's a trick, if you go to steam/steamapps/common/nimbus/data/GUI/layouts/FPS.layout there's a line that says:
<Property Name="Visible" Value="False" />
Change it to:
<Property Name="Visible" Value="True" />

And you should be getting a FPS meter.

This pleases me :D

Sairon
11-01-2010, 02:04 PM
Sairon, what about using a fixed tic rate like used in IDTECH 4 engines?

From my understanding they do it the same way we do it, with the exception of stepping physics in favor of rendering. This would decrease the perceivable frame rate more than now, but would allow the game to run the physics simulation at the same speed even on slower machines. I'll do some experimentation with this and see how large of a difference it makes, physics isn't that heavy on most levels anyway so it could perhaps work out nicely.

Saijin_Naib
11-01-2010, 02:51 PM
Interesting :) I like reading about this stuff. Of course, a settings menu which allows full control over effects,etc would help greatly as people could turn on and off what they want without "cheating" the game.

DJ Cryotek
11-01-2010, 07:30 PM
I just realized that there was an option to turn off trails, simply by picking the 'empty' trail selection. I'll see if that helps on the netbook when I get a chance.

DarthPsymon
11-02-2010, 04:55 PM
My fullscreen 'fix' isn't cutting it anymore. World 4-9 would drop me to 40fps in places :C

Sairon
11-03-2010, 10:41 AM
We've been able to do some optimizations on the particle front which should grant a couple of extra FPS in most areas, we still have some way to go in order for stable 60 across the field though.

I've been toying some with the fixed rate approach Saijin_Naib suggested, but it's kind of choppy at the moment so won't make it into the first patch, but hopefully the second. We should be able to get the first patch out by Friday. It will fix the most pressing issues and some minor enhancements.