Harald JOHNSEN:

Harald JOHNSEN:

This is another update for the cloud code, a lot of lines but this time I have started to add the doxygen doc.

Misc
====

- corrected a bug when RTT is not available, the current rendering context was
  altered
- if RTT is not available then 3d clouds are not drawn at all
- impostors lighting is now recomputed when the sun changes position
- distant objects are no more seen in front of clouds
- blending of distant clouds is a bit better now
- litle optimization of code (uses a less cpu time)
- use layer wind speed and direction (no more hardcoded wind)
- fov is no more hardcoded

Changes
=======

- clouds (cu only) are dissipating/reforming (experimental)
- compute a turbulence factor that depends on surrounding clouds and type of
  clouds (experimental)
- clouds shapes are defined in cloudlayers.xml
- type of clouds present in a layer is also defined in cloudlayers.xml
- cloud layers are generated from metar and other misc. data (in progress)
- added a rain effect around the viewer (enabled in the rendering dialog and
  when the metar property says so)
- added a lightning effect (enabled in the rendering dialog) : cb clouds spawn
  new lightnings
- added a dialog to select from different weather source : metar/property,
  a 'fair weather' environment and a 'thunderstorm' environment.