Re: [Flightgear-devel] Multi monitor setup: Splash screens disappeared since July

[Stuart B. <stu...@gm...>]

Hi Folks,

On Mon, 17 Oct 2022 at 10:11, Durk Talsma wrote:

> Hi,
>
> Stuart and I discussed the issue yesterday. While the fix below did not
> appear to resolve the issue for my, I did notice that I had the slider that
> controls the  maximum number of scenery tiles and objects cached set to a
> ridiculously high number. That is, I had it maxed out.
>

To give a bit more technical context because this may be an issue we need
to consider longer term.

This is the slider on the Rendeing Options that sets the number of PagedLOD
nodes that will be stored in memory (/sim/rendering/max-paged-lod).

We use “PagedLOD” OSG constructs in a lot of places - AI models, scenery
models and even the loading of STG files.  Effectively it allows OSG to
load something when it comes into range but otherwise leave it on disk.
Obviously that loading from disk has a cost so if we have the memory, it’s
worth keeping objects in memory even if they are temporarily out of sight.

While the slider goes all he way up to 10,000, we likely never had that
number of PagedLOD and  they were relatively low footprint.

WS3.0 uses PagedLOD for the scenery tiles themselves.  There are a lot at
different resolutions and they have textures.  So if we’re not unloading
them when they either go out of range or the views gets close enough for
the level below to be loaded then memory consumption is going to get very
high.

Assuming this is the problem that Durk and JP are seeing, then in the short
term we should limit the slider to perhaps 4000.

Longer term we might need to find a way to separate the PagedLOD of the
scenery from other elements.

Stuart

>