Hi Wang Rui, On Fri, Jan 8, 2010 at 1:16 PM, Wang Rui <[email protected]> wrote: > According to my experience, setLODScale is inappropriate in some > cases. While rendering a huge paged area to a large poster image, for > example, a 1GB lake area to a 20000x20000 poster, it will be really > inefficient and cause a serious frame drop if all the high-res > children were loaded at the same time (when lodScale is set to a low > value). That's a situation I have encountered before, and that's why > osgposter is born. :)
OK I understand this issue - it's an issue of balancing memory load of trying to combine high LOD levels over a wide area at once. So breaking it into each tile helps keep the load down. > This example divides the screen into M x N tiles and render these > tiles to images one by one. While rendering each sub-image, it just > tries loading all the high res children inside this tile, which > reduces the burden of the system. These may appear cumbersome and not > easy to read, but I seems not to have better ideas to control only > parts of the scene's paged nodes. I wonder if the new system for capping the number of PagedLOD's might help out here. I'll need to review your code again with the above insights in mind to see if I can understand it more clearly. I'll also ponder on whether LODScale can be used in a away that doesn't just result in too many tiles being demanded at once. > Attach includes some bug fixes of the osgposter example. If the code > seems too heavy, I'd like to use setLODScale instead to make it > clearer and only focus on rendering large posters at present. :) Thanks for fixes. I'm about to head out for the afternoon so my next review will have to wait till later, possibly next Monday. Cheers, Robert. _______________________________________________ osg-submissions mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-submissions-openscenegraph.org
