Thanks to Hooray who helped me setting up the CMake environment and the
guys at Infocare who finally managed to fix heat management of my
computer, I am now back on the devel tree. I've done a few tests yesterday
and identified a list of weather-related issues which I think should be
addressed (unfortunately, I can't do all myself).

(all refers to GIT as pulled yesterday afternoon and FG, SG and FGData in

1) Local Weather places clouds at the wrong altitude. (I will fix that).

2) The GUI is not consistent with the system (I will fix that)

3) High-altitude single-layer non-rotated clouds get shaded when the
ground gets shaded (I verified that they are subject to
/rendering/scene/saturation, but I believe I can undo this dependency in
the model xml wrapper - I'll try to deal with it)

4) Clouds now appear to be loaded in discrete lumps when they come into
visual range rather than gradually be faded in via transparency which
looks a bit ugly from high altitude - Stuart, is this intentional and a
performance-related issue? I have verified that the corresponding tile is
already loaded, so it's not something my part of the system does.

5) Changing the cloud density slider with LW clouds in the scene still
erases all clouds for me. Imho, would be a net option to have. Stuart,
what are your plans?

6) External rain textures are visible through clouds from above, looking
very silly. As far as I understand, since rain textures are true models
with 2d billboard animation whereas clouds are sprites with shader
rotation, the issue here is the render-bin again (?). I see three
possibilities - either we write a 2d rotation shader like the cloud shader
and use it for the rain textures and the infrastructure to go with it,
then rain is just like clouds and it should be fine. Or there is a way to
assign a render-bin somehow to the model as it is loaded. Or external rain
textures go away for the moment.

7) Similar problem with non-rotated high-altitude clouds - they are always
drawn in front of any other clouds, which looks silly when you see them
through a low overcast layer. Most of the time it's not so bad though,
since clouds on clouds is low contrast. So again, either they get a
non-rotating cloud shader and the infrastructure (difficult, since they're
really on curved sheets modelled to follow the cloud structure) or they
can be assigned to a bin which does the sorting right. Or they stay as
they are.

8) Local Weather has no precipitation rendering. This is due to the fact
that the system uses its own layer altitude definition and a 3d definition
of where rain is falling, whereas the precipitation rendering system uses
a lowest altitude criterion. Since lowest layer altitude is always zero
when local weather is running (it uses its own cloud altitude management
and since clouds need to be placed with offset to the layer, it's easiest
to make that layer zero) Local Weather has never rain unless you fly to
the dead sea (not much chance of rain there either...).

Could someone please provide a dumb rain and snow flag which always
renders rain when that flag is set and leave it to the weather system to
set/unset that flag as it sees fit?

9) Water shader (very impressive!!!) doesn't react to wind/overcast in
Local Weather. Vivian, Emilian - at some point we discussed an interface
of how to pass the situation to the shader. Technically it's really easy
for me to write in any form you like - just tell me where you want to pick
up that info.

10) Skydome scattering shader - is now basically broken in overcast
situations when visibility is low, because the clouds fade rapidly but the
shader doesn't react, so more blue sky is seen when visibility goes down.
In October, I had a near-seamless solution to that involving the ground
haze shader, a modified skydome shader, and modified cloud distance fading
behaviour which did the trick both for local and global weather (which was
also posted in the forum as very experimental feature). Is anyone (Vivian,
Emilian?) still working on that - or should this better go into the next

All in all, the performance requirements of the current version are weird.
I took my Carrier-Ops flight from Vinson to Nimitz in the F-14b which used
to have good framerate (no terrain) and I ended up with 14 fps. Not really
improved a lot by switching water shader off... I then wanted to know how
far down it'd go in really detailed scenery and used the Lightning to
blast around Hawaii to Maui - with similar cloud coverage I ended up with
twice the framerate and a comfortable 24-30 fps. With the Concorde on the
runway in Seattle, I had a whopping 3 fps (never seen anything this
low...), but the AAr with the F-16 around Las Vegas gave me 34-40 fps
(again in similar clouds). Doesn't agree at all with my previous


* Thorsten

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