Networked Mame Games?

[Kilroy01]

Excuse the nube question....  but...

I know that over the years there have been various two player games where each player has his own screen.  These usually allow each to be played as a separate game or allowed playing head to head.  Is there a way of linking two MAME cabs to allow this?  Has MAME added this capability or plan on doing so in the future?

[vrf]

That would be a really cool feature, although it probably wouldn't be official MAME since it wouldn't really jive with the "documentation" thing.

I'd love to hook my single-player cab up to a second one for head-to-head games.

And then... Internet tournaments? 

[Kilroy01]

To clarify my first post, I have already come across MAMEK and Kaillera.  From what I understand, they allow basically two people to see the same game on their individual screens.  I'm talking about the capability such as a racing game where each player sees the race from their own perspective.  Not just the same image on both monitors.

VRF...   I know that the official MAME project is to document video games so that they are not lost over time.  But if that was followed strictly, why make them playable?  Just dumping the roms alone would make them "technically" archived.  MAME is intended to also allow access to these games by making them playable.  In that case, wouldn't emulating the multiplayer feature of these games serve the same purpose?

[KenToad]

A big can of worms there, I would just search a little before saying anything for discussions relating to this topic, whatever that may be.   

[Kilroy01]

Not trying to step on toes or re-kindle old flame wars.  I'm just asking a question.  If the MAME devs, feel that this is not in line with their goals, so be it.  That is their choice.  They are the one that have made all of this possible. 

I'm just trying to learn what has been done or is planned for the future. 

I have run searches on the subject before posting.  Maybe I just didn't come across the one that you are alluding to.  I know that there are topics that are "touchy", but that doesn't mean that we should act if they don't exist.  We just shouldn't fight over them.

[Kilroy01]

I misspoke earlier,  according to mame.net...

"the main purpose of the project is to document the hardware (and software) of the arcade games."

In this case, the emulator that makes them playable is documenting the functions of the hardware that was in the cab.  I'm just asking if the "networked" games that were made have been included, as this was a function of their hardware.  I'm not looking for hacked versions of MAME to allow things that were never originally possible.

This question originated as I recently was looking at buying an old dual-screen cab that was intended as just such a set-up.  Just wanted to know if it was possible to set it up using MAME.

[tetsu96]

To clarify my first post, I have already come across MAMEK and Kaillera.  From what I understand, they allow basically two people to see the same game on their individual screens.  I'm talking about the capability such as a racing game where each player sees the race from their own perspective.  Not just the same image on both monitors.

Well, for the most part, MAMEDEV wants nothing to do with netplay.  Kalliera and similar are considered as blasphemy to most of the core MAMEDEV.  Chief reason being they add complexity and functionality to games that was not present (it's not just mirroring a display - it's making net code, code to sync the games, handling, etc.  A lot more than you think).

I doubt they all hate it, but you can ask at the MAME forums if you want to shake the hornet's nest.  Easier to just search as they have that chat on the forums every so often anyhow (you're not the first and won't be the last to ask).

VRF...   I know that the official MAME project is to document video games so that they are not lost over time.  But if that was followed strictly, why make them playable?  Just dumping the roms alone would make them "technically" archived.  MAME is intended to also allow access to these games by making them playable.  In that case, wouldn't emulating the multiplayer feature of these games serve the same purpose?

Just dumping the roms archives the games themselves, but not the corresponding hardware.  Further, without being able to run the games, how can the behavor of the games be checked?  Roms aren't always dumped right the first time, and bugs / anomolies in emulation of the core of systems isn't always found until put to gaming.  Strictly speaking they don't need to LEAVE playability in for our sake, but why take it out when it bring so much joy to the masses?

[tetsu96]

This question originated as I recently was looking at buying an old dual-screen cab that was intended as just such a set-up.  Just wanted to know if it was possible to set it up using MAME.

Maybe the game wasn't networked.  Some games are dual screen but each screen is for a single player (lode runner comes to mind, others too).  That's all 1 system when it comes to emulation.

Others, like Crusin' USA, are actually seperate systems linked together and I'm not sure what is done in that case (they're using proprietary communications so just implementing "netplay" thru TCP/IP wouldn't be accurate most likely)..

[Kremmit]

First, to the people talking about the MAMEdevs not wanting to implement any kind of net play:  I'm sure they don't want to add it to games like Mario Bros or Street Fighter II, as those games didn't have it to begin with.  But I've got to believe that once they start emulating games like Cyber Sled or The Grid, they'll want to tackle this- it's fundamental to the games.  You just can't play a multi-player, multi-POV game with only one person on one computer.  What're you going to do, run around and shoot at the walls?

Multi-monitor games already exist in MAME; like Punch Out! and Darius.  It stitches all montor's views together as one big screen- check MAME's output of these games to see what I'm talking about.  A Windows PC with multiple monitors can be configured to split these screens back up.

There's no reason this can't be done with multi-monitor head-to-head type games, as long as they run on a single set of game boards.  The problem is with games that network across multiple cabs- one solution would be for the MAMEDevs  to find a way to carry the game's native communication protocol over TCP/IP.  It could probably be made to work for computers networked locally, but the lag would probably make in unworkable for 'net play.

The other way to make it work would be to run multiple instances of MAME on one PC, and virtualize the networking between MAME instances.  I don't think current consumer-grade PC hardware is up to that task yet, considering the games we're talking about now are all fairly modern, and slow in emulation already.

Still, it'd be fun- I'd like to play Cyber Sled at home.

[vrf]

I was thinking older games. It would be fun to play The Simpsons or Tetris or SFII with another person in another city. Like Xbox Live Arcade.

[Kilroy01]

Thanks Kremmit.  That is the answer that I have been looking for.  Guess I should have specified dual-POV games.

I know that even the fastest PC's can't handle some games, much less run dual-instances of the games, but has any attempt been made toward the games that ran on singular hardware?

 

[tetsu96]

The problem is with games that network across multiple cabs- one solution would be for the MAMEDevs  to find a way to carry the game's native communication protocol over TCP/IP.  It could probably be made to work for computers networked locally, but the lag would probably make in unworkable for 'net play.

The other way to make it work would be to run multiple instances of MAME on one PC, and virtualize the networking between MAME instances.  I don't think current consumer-grade PC hardware is up to that task yet, considering the games we're talking about now are all fairly modern, and slow in emulation already.

Still, it'd be fun- I'd like to play Cyber Sled at home.

I hear ya there and yeah, they'll probably be networking those together at some point (I thought it sounded like I was talking multiplayer with just single cabs since I made the reference to Crusin USA - that was multiple cabs linked together (and Cybersled is, and Daytona when that gets emulated, and I don't think I played the grid but I get the point, etc).  The issue comes to how to emulate the link because of the proprietary communications.  Is the best approach to use TCP/IP and tunnel the proprietary protocol through that?  Link machines together using USB or Parallel Ports?

I actually thought that the linking code in Cruisin was emulated but just connected to null via code.  Maybe someone who keeps track can give the scoop.

And who knows as far as multiple instances on one box.  I was about to say I doubt that'll happen, but with dual core getting more popular and memory / CPU increases, who knows.

[Kilroy01]

Went back and checked and the cab was originally a Time Crisis II cab.  It's what got me interested in the subject.

According the mamedatabase.com, it is in the works, but still listed as unplayable.  The screen resolution is listed as 1024x480, so I'm assuming that's covering both screens.  Isn't this games a dual-POV?  According to KLOV, it allowed for solo play or linked play, but it says that solo in 1st player locks out the other player.  Wasn't it just locked out of joining the 1st game but able to start and play a 2nd game independently, but simultaneous with the 1st? 

I never got to play this one, so I am unfamiliar with it. 

[KenToad]

Still, it'd be fun- I'd like to play Cyber Sled at home.

True, Cybersled is not a bad game and I did throw a few Alladin's Castle tokens in there once upon a time.

[SavannahLion]

Maybe a dumb thought here, correct me if I'm wrong.

Haven't we reached the point now where some of the more modern arcades run a stripped down Windows? I've seen BSODs on more than a few machines lately.

The segment of games that would require linking emulation would be relatively small. As more and more modern games are run on top of an OS like Windows, then there would be no doubt that the networking code (if any existed) would be TCP/IP or something similar.

Of course, if that were true, then the MAMEDEV team has a bigger project on their hands since they might end up having to emulate the OS when newer versions drop legacy support. The WINE and Cedega teams has a hard enough time keeping their ---Cleveland steamer--- together during updates.

Of course, I could be completely wrong about the BSOD's and what I saw were just bootleg systems running Windows.

[u_rebelscum]

Adding emulation of any arcade-networking raises a lot of issues.

The first was demonstrated in this thread: confusion between netplay (any game, bad to mamedev) and net emulation (emulate connections original game had).  When mame gets net emulation (and the news gets out), people with think that mame has netplay, and get mad when they find out it doesn't.  Imagine something like this thread, except not so nice, with 1000 mad newbies complaining over at mame.net.  This is enough for most of mameDev to want to stay away.

Next is lag, or "ping time".  Most systems that connected directly to each other had very short lag times, even if the speed (bandwidth) wasn't anything near gigabit.  The games were written so that they need that short lag to stay synced, etc.  There are extra steps due to emulation (emulation of arcade "netcard" & protocol (x2, one per computer), PC OS & driver limitations (x2), PC card limitations (x2), and the network limitations, each adding to the lag time.  The only saving grace on this is the original speeds were mostly around the 1 to 10 megabit level.  This makes it possible that the faster 100 Mb & 1 Gb networks may catch up for added lag time.  Even so, I doubt any internet connections will have low enough lag times to work in most cases. 

The exception to the lag time problem are the internet or modem connected games.  However, this often was just to trade scores or profiles, which needed a central location to connect to, and didn't show in the play. 


Next is the emulation (of course).  And, no, the PC network card can't be used to do the emulating just like video cards can't.  The hardware token rings and other non-ethernet networks as well as the now stardard tcp/ip ethernet were used, and each will need to be emulated.

[SavannahLion]

Next is the emulation (of course).  And, no, the PC network card can't be used to do the emulating just like video cards can't.  The hardware token rings and other non-ethernet networks as well as the now stardard tcp/ip ethernet were used, and each will need to be emulated.

Taht would be interesting if my cache of token-ring cards actually become valuable and needed again 

[u_rebelscum]

Haven't we reached the point now where some of the more modern arcades run a stripped down Windows? I've seen BSODs on more than a few machines lately.

The segment of games that would require linking emulation would be relatively small. As more and more modern games are run on top of an OS like Windows, then there would be no doubt that the networking code (if any existed) would be TCP/IP or something similar.

Yes, but you're not thinking on the right level.

Mame emulates the hardware (CPU, video card, sound card, and if ever network card). 

The ROMs contain the software.  That means the ROMs for these games would include windows + drivers only for the specific network card in the cab.  Much like the voodoo video card, it doesn't help mame.

If mame correctly emulated the network card, mame would not worry about protocols at all.  The game packets the info in whatever protocol and sends it to the card.  Mame emulates the card, pretending to send like normal, but really just embeding the packet in a tcp/ip (or udp or whatever) packet.  When the packet gets to the other side, mame gets the packet and gives the game the packet the game expects in the protocol it expects.

OTOH, mame could fake emulate the card (think sound samples), but then mame would need to know the different protocols.  Harder to code IMO, and not as in tune with mame's goals as emulating the card.

That said, knowing the protocols would really help in emulating the network cards.  And it probably will be easier to emulate a tcp/ip over ethernet than a token ring over ethernet.

[SavannahLion]

I think I see your point, but doesn't it go in the other direction too?

Someone mentioned that some controls are being sold standard with integrated USB controllers because the arcade cabs themselves are becoming more PC-like. On Happs, I see they sell what appears to be standard HDD's (Killer Instinct?), CD/DVD drives (Golden Tee), SIMMs and I'm sure a whole gammut of other components that were originally found only on PCs.

If these components are so readily interchangeable (correct me if I'm wrong), wouldn't the logic extend to NIC's as well? A 3Dfx GPU is a brand name as well as part of a very specific tool suite. It's not like you can plunk in a nVidia and expect it to run code specific for a 3Dfx GPU. But I doubt most people popping tokens is going to care about whether the NIC in a particular cab is from Linksys or 3Com. Linux has about a dozen core drivers that works for nearly every NIC.

I'm really making a lot of assumptions here. If the NIC is just a straight IC on the mainboard and the arcade manufacturer went with one supplier instead of the cheapest, then this discussion is probably moot and I'll kindly step out.

I'm not trying to be an ass or anything, I'm just trying to get my facts straight here.

[u_rebelscum]

I think I see your point, but doesn't it go in the other direction too?

Someone mentioned that some controls are being sold standard with integrated USB controllers because the arcade cabs themselves are becoming more PC-like. On Happs, I see they sell what appears to be standard HDD's (Killer Instinct?), CD/DVD drives (Golden Tee), SIMMs and I'm sure a whole gammut of other components that were originally found only on PCs.

If these components are so readily interchangeable (correct me if I'm wrong), wouldn't the logic extend to NIC's as well? A 3Dfx GPU is a brand name as well as part of a very specific tool suite. It's not like you can plunk in a nVidia and expect it to run code specific for a 3Dfx GPU. But I doubt most people popping tokens is going to care about whether the NIC in a particular cab is from Linksys or 3Com. Linux has about a dozen core drivers that works for nearly every NIC.

I'm really making a lot of assumptions here. If the NIC is just a straight IC on the mainboard and the arcade manufacturer went with one supplier instead of the cheapest, then this discussion is probably moot and I'll kindly step out.

I'm not trying to be an ass or anything, I'm just trying to get my facts straight here.

You're not being an ass.   It's just that mame and mamedev have a certain view that does not focus on short term fixes (usually ) or speed, but instead on ease of long term upkeep, OS independency, ease of understanding the code, and most of all "documentation of the original hardware over playablity".  Once you understand the "mamedev view", you can see why mame won't directly access the NIC.

Let me try a simple example:

Some arcade machines used 386 CPUs.  Does mame let the game directly use the PC CPU?  No, it emulates the 386 just like all other CPUs it emulates.  The same applies for all video cards, sound cards, hard drives, CD drives, joysticks, buttons, spinners and everything else (including NICs once they're added). 

If mame adds support for arcade NICs, mame will emulate the original hardware, and use an OS independent method of transferring the information.  Mame won't try to use the PC NIC to offload any emulation; the PC NIC will just be for transporting the encased info. 

And while it's possible to do it closer like you describe (as some emulators might try), it would be OS dependent, not portable, multiply the complexity of the networking code ( # NICs emulated *  # PC NICs supported), and probably too much a hack to even be close to be "emulation".