Stella over the net?

[toymailman]

I have a question. Does the Stella emulator work over the internet? It would be cool to enjoy some of the two-player games again. Having an emulator that can "connect" up Atari fans around the world would be too cool!

 

If not are there any plans to have this made. IMO it would be the best feature possible.

[SeaGtGruff]

I have a question. Does the Stella emulator work over the internet? It would be cool to enjoy some of the two-player games again. Having an emulator that can "connect" up Atari fans around the world would be too cool!

 

If not are there any plans to have this made. IMO it would be the best feature possible.

You can play Atari 2600 games on a web site using (if I remember correctly) JStella, which is a Java version of Stella. But I don't know of anyone who's been able to get a "multi-player online" setup working, like two people playing against each other online at "Combat," or four people playing "Warlords," etc.

 

Michael

[Nukey Shay]

Yup...AFAIK, there was only 1 emulator that was supposed to have 2600 netplay. But I've long since given up searching for (apparently) non-existant dll's that it required.

[+batari]

There has been recent talk about how netplay might be added to Stella. Before this happens, the ability to undo and correct several frames of gameplay is an absolute necessity given that typical broadband internet latency is still 5-10 frames. And even then, it will not play exactly like it would on a real console in your living room.

 

For example, suppose you are playing 2p Combat and have a latency of 90ms. Player 1 fires a missile but player 2 would have no way of knowing this until 5 frames have already been drawn. So Player 2's Stella would likely have to effectively skip those frames of gameplay to sync with the other player. You'd see a missile appearing some distance away from the tank and would get only a portion of the firing sound. Alternatively one could reduce the frame rate but things would get jerky.

 

In a fast-action game like Warlords, the latency would be a killer, as one game would likely think a player missed a ball and the castle would be hit, but once the game corrected itself, the castle would repair itself and the ball would appear in a different place. It might be marginally playable but it would take a while to get used to the weirdness.

[cosmosiss]

Doesn't PCAE come with Kaillera?

 

I say we start a room!

[+stephena]

There has been recent talk about how netplay might be added to Stella. Before this happens, the ability to undo and correct several frames of gameplay is an absolute necessity given that typical broadband internet latency is still 5-10 frames. And even then, it will not play exactly like it would on a real console in your living room.

Batari is right; network play would require an infrastructure to 'rewind' state information. I'm hoping this infrastructure will be in the next version of Stella, and I'm working on it right now. When you think about it, movie recording, state rewinding and network support are all related. You basically have to be able to treat the emulator as a 'VCR of input events' (for lack of a better term), and be able to rewind and/or fast-forward through those events, and have the emulation still be accurate.

 

I actually have rudimentary support for movie recording already done. There's no UI for it, and it hasn't been extensively tested, but it does work for all the ROMs I've tried. In save mode, it works by saving the complete emulator state, and then every frame it saves all registers that would change on the real system (those related to controllers and console switches). In load mode, it loads the complete emulator state, and then each frame reads registers from the state file.

 

For those familiar with network programming, I think you see the similarities. Reading from the network is exactly like loading a movie recording, and writing to the network is exactly like saving a movie recording. Of course there are issues of latency to deal with, but basically the underlying emulation doesn't know or care where the events come from. As long as the framerate and event 'injection' are synchronized, the emulator works as normal.

 

I'm not even going to suggest when this feature might be added, or when the next release will be. But rest assured that the feature will appear eventually

[toymailman]

I'm not even going to suggest when this feature might be added, or when the next release will be. But rest assured that the feature will appear eventually

Awesome!!