GetRootLocalPos

While writing another function, I got thinking about the whole attachment local root rotation problem (you need to know the local rotation of the root prim in an attachment so you can use PRIM_ROTATION). I came to the conclusion with all the new(ish) functions, it is now possible to actually work this out.

1. You know the position and rotation of the avatar, thanks to llGetObjectDetails.
2. You know the attach point (llGetAttached)
3. You know the combined rotation and position (llGetRootRotation & llGetRootPosition)

It should just be a matter of subtracting the one from the other and canceling out the attach point offsets.

Something like this should work... <lsl>//list offsets = [ 0, <0.5, 0.5, 0.5, 0.5>, <0.0, 0.0, 0.70710678118654752440084436210485, 0.70710678118654752440084436210485>, 0, 0, 0, 0, 0, 0, <-0.5, -0.5, 0.5, 0.5> ];

vector GetRootLocalPos() {

   if(llGetLinkNumber() <= LINK_ROOT)
       return llGetLocalPos();
   integer point = llGetAttached();
   if(point)// (((child-global - avatar-position) / rot-avatar) / rot-root) (/ attach-offset?) - child-local == root-local
       return (((llGetPos() - llGetRootPosition()) / llGetRootRotation()) / GetRootLocalRot()) - llGetLocalPos();
   return llGetRootPosition();

}

vector GetRootLocalRot() {

   return llList2Rot(llGetLinkPrimitiveParams(!!llGetLinkNumber(), [PRIM_ROT_LOCAL]), 0);

}</lsl> -- Strife ^{(talk|contribs)} 08:35, 6 May 2010 (UTC)