
- When in 2 players mode, it seems that the frame speed is not the same.
- Shared Memory may stay persistant when killing speedx.
  (Currently, speedx only tests if this shared memory exists to reinitialize
  it.)
- core dumped when data directories are not found.
- if the speed is too fast the road seems to go in the opposite side ..
- .. and many to come .. 

TODO :

- Better physics
- Hills and holes on the road  (Voxel ?)
- Other cars -> Use Panorama and release the source.
- Make each opponents different color.
- Multi-car racing
- Why not a mini ray-tracer for the cars ?
- Menu with choice and Radio car chooser for Music
  (keys, level, music, road and cars)
- Car collision is badly done when the 2 cars hit on each side.
- Scenery around the road and landscape.
- Network gaming.
- Different kind of behaviour for the AI cars. 
- Best AI (better diffusion, not always the same speed, etc .. )
- high score, other laps etc ..
- Redim and smoothing of an XImage
- Show the turns numbers
- At the end of a course do another lap.
- Modify the code to manage installation directories and a user directory.
  (Secure the code when directories don't exist -> core dumped).
