On Saturday, September 18, 2010 18:32 Durk Talsma wrote: > Given, my observation that cycling through all the viewpoints, will restore > the visibility of tiles that have gone lost, and flag tiles that were visible > during the previous view cycle invisible, makes me suspect that something in > the code that determines tile visibility may go astray after a prolonged > number of tile crossings.
Thanks Durk, in fact your observations are very helpful! I also noticed that tiles sometimes reappeared - i.e. when I paused the sim. But it's not the pausing that helped, but indeed the view cycling - specifically cycling through the tower view helps. The tower of the home airport is far away when the problems start. The tile cache isn't big enough to hold all tiles of two different locations - so switching to the home airport and then back causes a reload of all/most tiles. And it's indeed connected to the number of scenery tiles covered by the flight as you mentioned - not the distance in the first place. I found that I'm not seeing any problems unless the tile cache is filled to its maximum. And when I circle in my regular home airport area, the cache is not completly filled - and I have no issues. I'm currently monitoring what's going on in the FG Tile Manager and SG tile cache module. The tile cache makes its decision to kick a tile from the cache purely based on a timestamp (oldest tile get's kicked). This strategy works nicely when flying in a straight line (oldest timestamp => tile is furthest away). But not so great when you fly sharp turns (oldest tile may still/again be right in front). I suspect there is some kind of connection to the problem, e.g bad strategy kicks tile in front of plane from the cache, and then this tile does not get reloaded. It would explain why I often see issues with a disappearing destination airport: you fly (almost) straight from A to B - and then, at some VOR, you make a sharp left or right turn to line-up for the approach - and soon afterwards I start seeing most issues (on short final :-(...). Well, just a theory so far. I'll do a bit more digging. Any hints still welcome. cheers, Thorsten ------------------------------------------------------------------------------ Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
