Hi John, As the author of the 3D clouds system, and the OSG random buildings/objects re-implementation, this is obviously an area of interest to me :)
Comments inline below. On Mon, Jun 18, 2012 at 2:20 PM, wrote: > By way of an example, consider the 3D cloud system. > > Given a three projector system, each CPU is configured in a similar manner > as before for a multi-monitor system; i.e. there is a master FDM, the slave > FDMs are disabled and each CPU is bound to a display. I don't recall the > exact syntax but for those who have run multi-monitor display systems you > understand. The doc files and readme's provide a good description of how to > implement this configuration for those not familiar with the setup. The > down side in this approach is that each CPU creates it's own graphics > context and dynamic/random scenery objects are not sync'd. It has been a > year or two since I last spent any time digging into or running FlightGear > with master/slave machines. The current 737/747 sim runs on a single CPU > with three projectors to make use of all the "eye-candy". But I believe the > above assertion is still true. I think random scenery objects, trees and buildings are placed based on the terrain tiles, and a random seed generated statically for each tile. So, it should be the case that the same set of random objects are generated for a tile no matter what the graphics context, and the same set of objects should be generated each time the sim is started. Put it another way: Random object/building generation should be completely deterministic. If that's not the case, then there's a bug I should look into. > In the case of the cloud system, something similar might be possible. The 3D cloud system generated by "Basic Weather" is generated based on the position of the viewer when the clouds are generated. For a multi-computer system, starting position will be the same, so the same set of clouds should be generated on each computer. (I should double check the random seed generation is correct just in case). Again, if that's not the case it's probably a bug. I don't think the problem is a lack of a shared memory OSG tree. I think the issues you have with objects "ending" at the screen boundaries is a different one. Could it be due to over-aggressive culling? Could you explain in a bit more detail what is wrong? Unfortunately I don't have a multi-computer setup to be able to test this myself, so I'll need a bit of help really understanding the problem. Screenshots will probably help. -Stuart ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
