[Celestia-developers] Changes to Lua

[Harald S. <har...@us...>]

Hi,

I played around with the lua-interface in celestia/celx.cpp, and added
some functionality. My local changes are:

- new type vector (wrapper for Vec3d) with:
  - getx(), gety(), getz() 
- new type rotation (wrapper for Quatd)
- changes to position:
  - getx(), gety(), getz()
  - vector position:vectorto(position)
  - position position:addvector(vector)
- changes to frame:
  - to and from accept either position or rotation
  - time is now second argument and optional 
    (defaults to appCore->getSimulation->getTime()) 
- changes to celestia:
  - flash() now accepts seconds arg time
  - vector celestia:newvector(x,y,z)
  - rotation celestia:newrotation(vector, angle)
  - Bugfix for newframe(string, target)
- changes to observer:
  - observer:setposition(position)
  - observer:setorientation(rotation)
  - observer:rotate(rotation)
  - observer:lookat(position from, position to, vector up)
  - observer:gotolocation(position) (recommended in TODO for goto)
  - frame observer:getframe()
  - observer:setframe(frame)

I tried to pick up the traces in the code of what was planned anyway
and avoid changes to existing code. If there are no objections, I
would like to integrate my code into the official codebase and
possibly add further changes (any suggestions?) and create some
example-scripts.

All changes would be in celx.cpp, except for a small bugfix in
celestiacore.cpp (celxScript can become NULL during call to
celxScript->resume in CelestiaCore::resumeScript, just after checking
that it is *not* NULL).

 Harald