VROC: Virtual Racers' Online Connection

Technical Notes

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Table of Contents

Problems Connecting

Question: When I get to GPL's multiplayer screen, I only get COM ports (3 and 4) as the connection alternatives, not the "TCP/IP node". Are there any core.ini files that would work in this situation?

Most likely you need to have GPL look up the IP address of your machine using an alternate method.

DSL and cable connections often need to use an alternate IP address lookup method with GPL. This also happens with AOL dialup connections and may happen with any connection in which the ISP uses DHCP to assign the customers' IP addresses.

Using a text editor such as Notepad, simply create a file called core.ini in your main GPL folder (if you installed GPL in the default location, this will be C:\SIERRA\gpl). Then add these lines to that file:

[ Communications ]
alternate_ip_addr_lookup = 1  ; Find IP addresses another way

There are details about this parameter in GPL's readme.txt file. You'll find this in your main GPL folder.

Question: Sometimes when I connect to a server, I get to the Weekend screen in GPL but there's no green button, and then I get kicked back to the Multiplayer screen.

This is a known problem in GPL. Usually you can simply try to connect again, and the connection will be made properly.

Note: on the Track Selection screen, after you connect, the Practice Remaining field will first show the initial number specified by the host (usually a round number like 15:00, or 30:00) and then changes to 0:00. When the initial handshaking is complete this number will switch to the time actually remaining, and start counting down. It's a good idea to wait until the number starts counting down before hitting the green button to advance to the Weekend screen.

If the Practice remaining doesn't start counting down within about 30 seconds, either the handshake has failed, and you'll get kicked back to the Multiplayer screen, or practice is over, and you can advance to the Weekend screen. If practice is over, you won't get a green button at the Weekend screen. In this case, simply wait for the session to switch to race, and then advance to the grid.

If you fail to connect consistently to a certain server, try another server. If you fail to connect to many servers, you may have a problem with your Internet connection. See Alison's GPL Online FAQ for information about how to tune your DUN and modem settings, and try new ISP's until you get good pings.

Problems When Racing

Problems you man encounter when racing online include disconnects, reduced frame rate, frame stuttering, warping, winking out, screen flashes, and giant warps. These problems can usually be resolved by taking a few simple steps. This section should give you the background to do so.

If you find you want more information, see Eagle Woman's GPL Online FAQ and our Development Notes.

If you've raced on VROC for long, you'll have noticed a number of issues that seem to affect online racing. These include:

  1. Some people disconnect frequently, and sometimes when such people join a session, other people get disconnected.
  2. Sometimes people do impossibly fast lap times, like one or two seconds or less.
  3. Sometimes people get disqualified for going backwards, or get a black flag for cutting the course, even when they haven't.
  4. Sometimes other cars disappear and reappear a large distance away. If you're a client, this may be associated with an abrupt flash of the screen, and a strange interruption in the sound of your car. Sometimes the other players' cars make strange warbles in their sound too.
  5. When races start, if there is a collision, suddenly cars start disappearing and reappearing all over the place, and crashes seem to be crazily violent.
  6. Sometimes the sim pauses right in the middle of driving, or runs horribly slowly, or does other nasty things related to system memory.

Below are suggestions about what you can do to prevent these things, followed by a discussion which explains why they happen. Following that is an explanation of how to save longer replays on machines with 64 mb of memory.

What to Do

To address problems 1 through 4 above, read Alison's GPL Online FAQ and follow my advice! If you don't have time to read the entire FAQ, here's a synopsis:

  • Download and install the GPL Disco Fix.
  • When hosting, use VROC's recommended Bandwidth Settings.
  • If you can, switch to a high speed digital Internet connection, such as cable modem, ADSL, or ISDN (preferably not using the serial port!) If that's not possible, please seriously consider a USB modem or an Internet Gaming Modem!
  • Adjust your graphics and sound settings in the sim's Options, and/or upgrade your hardware, so you get 36 fps all the time when you are racing online! A digital sound card can make a big difference here.
  • If you have a Winmodem, discard it immediately in favor of a real modem! Winmodems lack certain critical components, instead offloading more communications workload onto the CPU - exactly what you don't want for online racing!
  • Only join races on the VROC race list that show ping times consistently below 500-600 ms, and preferably below 300 ms.
  • If you rarely or never see races which meet the above requirement, tune your DUN and modem settings (see Alison's GPL Online FAQ and Doc Wynne's advice about setting MTU size)
  • Try new ISP's until you get good pings.

To avoid collisions at the start, do the following:

  • Practice standing starts offline until you can get a good start, keeping the car going dead straight, every time. You should be able to consistently make it to the first turn without losing more than two or three positions to AI cars in single player races.
  • Drive very carefully at the start, and make every effort to avoid a collision. Remember that the information you are getting about the cars ahead of and around you may be almost a second old, so leave plenty of room ahead and to the side.
  • Listen for other cars around you at the start.
  • If you have appropriate buttons on your controller, assign them to your sim's Look Left/Look Right functions, and use them!

To avoid pauses and other memory-related issues, see Doc Wynne's advice about Windows 95 memory on the next page.

Changing Replay Length in GPL

I'm not sure who wrote this but it sounds like it came from someone at Papyrus:

We use a conservative heuristic to determine how large a replay buffer to allocate to reduce the likelihood of paging during gameplay. GPL will always allocate a replay buffer of at least 2M, however, even if the heuristic says that's too much. On a 64M machine, you'll pretty much always be in this 2M zone. You're welcome to experiment with larger replay buffers, but I found that even doubling the buffer to 4M on a 64M machine lead to significant paging.

Play with this at your own risk.

In the same directory as the gpl.exe program, use Notepad (or another plain text editor) to create a text file named core.ini In this file, add the following two lines:

[ Replay ]

replayMemoryOverride = X

where X is the number of Kbytes of memory you want to dedicate to the replay buffer.

Several people have reported increasing memory for replays with no ill effects. However, keep in mind Doc Wynne's comments on memory allocation in Windows on the next page.

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