comme les autres, bounding box

pas faire interpreter, transform gml in caml prog
 and compile it and run it
 (perhaps i have those idea by subconscient cos vouillon done that
  perhaps i have not think about it if i have not seen fastly what has
  been done)

vouillon: if surface fonc dont use his argument, then
 make specialised code  ??

leroy: 
 keep track of the lack attenuation, when become negligeable, stop the recursion
 hash-cons the ident in the GML interpreter (more efficient lookup)
 as voullon, when surf_fonc dont use argument
  how do this ?? introduce a constructor in value Unknown and then try
   eval the func, as Unknow neved use in PM, we must have a match_failure :)
   ruse
 et en plus test if constant with face
   (how he do this ?? he put the different value for the face, and for each (depend of object)
     make the same tech than before, by putting unknown
  => a surface fonc is either SurfConst | SurfArray (for each face a constant) | NormalDynamic
 use the matrix transfo for transfo the ray, and then
  make specialised intersection fonc (that is with always a plane with y = 0, ...
  (PAD: better ?? not better to do the transfo of object directly ?? than do
   each time transforme the ray ??)
 unrolling of the matrix ops (deroule les foreach col { foreach line { ...})