Eddy Petrișor a écrit : > RCL wrote: > > >> There was no problem with synchronizing object positions/states, as >> there was only one piece of code that actually did the calculations... >> all the "clients" (including local one, which shared CPU with server >> part) just received the stream of object positions for a given frame >> and interpolated between two frames to match their own FPS rate. >> > > This is what should be done in wormux, too > > >> I guess the biggest difference between the above scheme and one >> implemented in Wormux, is that Wormux server communicates not the >> object states, but the "actions", that are used to drive the client >> code the same way as usual keyboard input would. >> > > And those, sometimes, expand on the clients differently. > >> But the actions seem to be able to come at any time and there's no >> notion of "server frame" in the Wormux code (e.g. a complete set of >> object states for a given time on server), so if some "rogue" or >> buggy/outdated client interprets some particular action differently, >> there's no way for the server to fix object position for him, or to >> even know about that, right? >> > > I think you managed to point out what I always thought to be a weak > pointin wormux' net code: clients shouldn't be allowed to make > calculations independently. There can be several things that can go > wrong with that: parallel universes (one player sees A dead, another > sees A alive), errors in FP implementation of one processor can cause > desyncs, etc. >
Numerous actions are synchronized to avoid such effects. Parallels universe exists only for the non players during one turn. > In the worst case, the client that is the current active one should be > the one dictating and distributing all the information about the > changes, while the others will just update the views accordingly. This is what is done at the end of each turn. The previous "turn master" send information about all characters (position, physical states, body animation frame, ...) and this is nearly what is done with some weapons like jetpack. > Since > we don't have a real-time game, there is no problem with the fact that > the active payer is ahead of the others. > > Anyway, we currently have a hybrid model that (re)synchronizes what you should be and let each computer computes other things. Switch to a full server computation is not as easy as some seem to think. First, all objects should be identified to serialize their information, this is currently not the case. Only characters have identifiers. Then, lot of data would have to be sent, probably to much data to send without compression. Switch from TCP to UDP is probably needed. Then, it means that we should recover states of information from partial information. If you plan to spend your next six month full time wormux debugging, go on... Regards, Matt (gentildemon) _______________________________________________ Wormux-dev mailing list Wormux-dev@gna.org https://mail.gna.org/listinfo/wormux-dev
