Generic network prediction

re: Generic network prediction

Promit — Fri, 26 Jun 2009 05:05:46 GMT

Nothing specific to say, but comments seem to have fallen off recently and I thought that was sad. It's nice to know you have readership, so I thought I'd say hi.

re: Generic network prediction

Asa — Fri, 26 Jun 2009 17:15:15 GMT

This is perfect. I'm mulling over networking in my DBP entry and this is exactly the kind of stuff I was confused about.

As with everything you've posted for the community, thank you so much man!

re: Generic network prediction

Matt — Fri, 26 Jun 2009 18:01:33 GMT

I agree. I never post, but read every blog. Thanks for all the info, Shawn!

re: Generic network prediction

dpramel — Sun, 28 Jun 2009 21:58:43 GMT

Ok, and now make a whole game on the xbox and see how the garbage collector kills performance when more than 2 players are in the session...

MS really needs to do something here. My game produces ZERO garbage without networking but a s soon as i turn it on it does a lot. Even using the unsafe code sample found in the forums didn't help much. As soon as you write float or Vectors in the session, the problem occurs.

Nevertheless a good sample - didn't know the where-syntax ;)

re: Generic network prediction

ShawnHargreaves — Sun, 28 Jun 2009 22:23:56 GMT

dpramel: it is entirely possible to make a network game with zero garbage. Have you used CLR Profiler on Windows to see exactly where your garbage is coming from? If you do that and can't work out how to avoid this, I would recommend posting about this on the creators.xna.com forums where I'm sure someone will be able to assist you.

re: Generic network prediction

dpramel — Mon, 29 Jun 2009 08:41:40 GMT

Hi Shawn,

have you seen this thread?

http://forums.xna.com/forums/p/13255/83721.aspx

But ok, i will profile it again. Thought it would be the packet writer (and was pretty sure it was...)

Daniel

re: Generic network prediction

ShawnHargreaves — Mon, 29 Jun 2009 18:17:46 GMT

That's a very old thread: the issue it is talking about no longer exists for the last two Game Studio versions.

re: Generic network prediction

Crag — Thu, 02 Jul 2009 16:02:50 GMT

You couldn't by any chance post the ' // Ship physics goes here.' bit :p

re: Generic network prediction

ShawnHargreaves — Fri, 03 Jul 2009 05:14:26 GMT

> You couldn't by any chance post the ' // Ship physics goes here.' bit :p

I don't know that that would make much sense without a ton of the supporting code. I actually filed a bug for our dev-ed team to consider if we could release any of the appweek products as mini-games, but I don't know if/when that might go anywhere.

My physics wasn't really that interesting, though. It all started with the Tank On A Heightmap sample, then I added some inertia and simple spring model for the ship to make it hover a bit above the ground plane, but so it would gradually bounce to new heights when flying over rough ground.

re: Generic network prediction

Crag — Fri, 03 Jul 2009 08:38:30 GMT

Ok. I noticed you have the Front and Up vectors in the State structure so I guessed you are using Vector math to control the Ships direction/movement. Thats the part I'm interested in because I want to use Vector math for my ship control but I can't find any simple, boiled down explanation of exactly how to manage it. e.g. Is it better to maintain a separate Forward, Up vector apart from the WorldMatrix or maybe its better to just have the Matrix and rebuild that directly. I'm unsure which method to use. I guess with the networking stuff it is better to maintain them separately as it would be a waste to send the whole matrix over the network. Maybe it is already in the Tank On a Heightmap sample. I'll take a look there. Thanks.

re: Generic network prediction

George Birbilis — Mon, 05 Oct 2009 02:45:18 GMT

haven't read through your code, but sounds like what is called "dead reckoning" in robotics etc.