Hi, Thanks to Jan Comans I've been able to sync the 3D clouds across three instances of fgfs running on a multi-core machine. This, in turn, provides for some very respectable frame rates of 40 to 50 fps per core with a three projector system with older generation Nvidia boards ( GT430 and GT440 ) on a 64bit I5 machine. The visuals will be just awesome once the collimated display is completed later this year.
However, all is not perfect in simworld. Since each CPU starts and runs independently there is a skew in sim time for each core and AI trsffic is just not usable with models "disappearing" into the screen edge and then showing up at the adjacent screen boundary a few seconds later. One possible solution is to start with the sim clock "frozen" and once all instances have booted and initialized send out a control packet via the native-ctrls protocols and unfreeze the clocks. A better solution would be to use the fdm packets to start the clocks since that protocol is already being used to sync the fdm slaves to the master. This network method will still have a bit of latency; probably the best solution is to have a freeze flag in a portion of shared memory accessed by all cores and then clear the freeze state once you are ready to run. This has an additional advantage of be able to stop and start all instances with microsecond accuracy. Just wondering if anyone has messed in this area and has some info/data on such things as to how much latency is tolerable before the AI models start "breaking up" across screen boundaries? Is there clock drift due to variations in delta t's for each CPU/GPU set based on rendering times for each screen? Any need to send out a local sim time standard to adjust for any drift and keep things in sync? Any thoughts, comments, suggestions would be appreciated and will earn credits for sim time if you happen to be passing through the Colorado Springs area. ;-) Cheers Jack ------------------------------------------------------------------------------ Learn Graph Databases - Download FREE O'Reilly Book "Graph Databases" is the definitive new guide to graph databases and their applications. This 200-page book is written by three acclaimed leaders in the field. The early access version is available now. Download your free book today! http://p.sf.net/sfu/neotech_d2d_may _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
