[osg-users] PagedLOD glitches

Robert Osfield robert.osfield at gmail.com
Fri Aug 26 06:58:44 PDT 2016

Hi Andreas,

On 26 August 2016 at 12:09, Andreas Ekstrand
<andreas.ekstrand at remograph.com> wrote:
> Is there any way to avoid glitches in the PagedLOD during loading of the
> higher level after the lower level has switched out?

Are we talking just a visual glitch or a frame rate drop, or both?

> When flying over my
> quad-tree terrain the tiles are flickering and the background color is
> visible a short while before the higher level has been loaded.
> One can of course override and implement logic that waits to switch the
> lower level of until the higher has been loaded, but maybe I have missed
> some existing setting?

The logic in PageLOD::traverse() that decides between which LOD's to
display depends entirely on the LOD ranges used for each child, if the
ranges are distinct then no two children of a single PageLOD will be
displayed at the same time.

If you built the database such that the PageLOD's overlap a bit then
you have a case where both a lower level of detail and higher level of
detail could be visible at once.  Given your description this sounds
like it may be possibility.  I wouldn't recommend building PageLOD
databases with overlapping LOD range though - they can abut but
shouldn't overlap.

The other possibility might be display latency, or if you have some
kinds of higher level effect for visually blending between LOD levels.


More information about the osg-users mailing list