> The main thing that bugs me with the system is that the view frustum
> culling
> around the edges of the screen is visible, so you continuously see the
> clouds being created and disappearing at the edges of the screen as you
> turn
> or change views.  If it was once in a while I could live with it, but
> it's continuous and perpetual and distracts from the
> overall experience. :-(

Hm, from the description this could be one of two things:

1) Clouds are 2d sheets placed into the scenery with a true orientation,
then the shader matrix magic grabs them and rotates them into an apparent
orientation. However, generically a sheet can be outside the view when
unrotated but in view when rotated while the shader acts (and rotates)
only when the object in its true orientation is inside the field of view.
Thus, for relatively large cloudlets and in directional corridors, it can
happen that an object would be in view, but isn't actually shown, i.e. a
cloud suddenly vanishes at the edge because the true position of the
vertices is no longer in the field of view, although the apparent still
would be.

There are a few solutions inside Local Weather to lessen the problem, e.g.
using smaller cloudlets at the expense of performance, down-scaling of
models in the shader so that the true model is much larger and more likely
to be in view than the apparent model. A clean overall solution would
involve applying the shader to objects slightly ouside the view. I suspect
that effect is also there for the default 3d clouds, although less
pronounced since they use on average smaller cloudlets.

All in all, I find this effect mild, I usually don't even notice it and it
goes away when you turn by 90 degrees (and hence true and apparent
orientation coincide). It bothers me about as much as trees suddenly being
drawn once you reach a certain distance to a forest-textured area... just
a little bit.

2) A while ago a video was posted here

http://www.easy-share.com/1912919971/Clouds03.mpg

which showed a view from the front window with many clouds. When the view
changed to the side window, for a second empty sky was visible, which then
rapidly filled with reloading cloud models.

What you describe here sound pretty much like that, and that is very
annoying.

It's not something I have ever seen on my computer, for me clouds behave
just as the default clouds, i.e. they are already there when I turn my
view, there is no culling and redrawing happening. For the case in the
video, I have verified that the effect doesn't come from within Local
Weather (I asked to switch off all Nasal loops which load and unload
clouds, and the effect remained unchanged).

My suspicion is that it is generic at least for Nasal-spawned models, i.e.
if you would place 1000 objects with the ufo around you and turn the view
rapidly, you would see the same thing.

I have never been to observe it in either 2.0.0 or any of my GIT pulls and
with no version of OSG I've ever compiled against. In short I have no clue
what it is, but I know that the problem lies outside the Local Weather
package.

* Thorsten


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