Hi, James Palmer schrieb am 13.05.2007 03:14: > Harald, > > You are correct, solution #1 does require the server to run all of the > FDM for all players in multiplayer mode. Does anyone know, which latency between control input and visible reaction is acceptable (== unnoticeable)? The worst case of the latency with the FDM running on the server is the sum of a) max. time between control input and next packet send (1/rate, e.g. 100ms at 10Hz) b) time for the packet from the client to the server (1/2 ping time, e.g. 50ms) c) max. time for the server to do the fdm calculation and sending of the next packet (the fdm calculation seem to be negligible compared to the other latencies, therefore we get 1/rate, e.g. 100ms at 10Hz) d) time for the packet from the server to the client (1/2 ping time, e.g. 50ms) e) time for drawing of the picture at the client (1/framerate, eg.1s/20=50ms)
The sum of the example is 100+50+100+50+50=350ms. The same calculation for the fdm running at the client (like it is today): a) 0ms b) 0ms c) 1/framerate, eg.1s/20=50ms d) 0ms e) 1/framerate, eg.1s/20=50ms results in 100ms. I think you can feel the 350ms latency, but I am not total sure. Maybe some could write a tool, which add some delay to any control input and check out, which latency can be felt? And think of force-feedback input devices (ok, not supported now), but there the maximum allowed latency is much smaller. Maybe it is easier, that the clients run their own fdm and the combat-server makes a test of the actual performance of the client against stored values, which could be generated by a script (maximum acceleration, turn rate, speed for several sets of orientation/speed). Maik ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
