So.. What do I mean by that? Well, I have a little bot I made that, 
currently, is fairly stupid about how it flies around. It occurred to me 
that I could improve it using a spline path, but then I also considered 
that this has a limitation, since I am using a "through the points" 
version, which doesn't allow you to "fine tune" the curve.

So, instead I am looking at this, an interpolated B-Spline:

n = llGetListLength(P);
// Create B, A and D list of same length as P here.
B[1] = -0.25;
A[1] = (P[2] - P[0] - D[0]) / 4;
for (i = 2; i < n - 1; i++){
   B[i] = -1 / (4 + B[i - 1]);
   A[i] = P[i + 1] - P[i - 1] - A[i - 1]) * B[i];}
for (i = N - 2; i > 0; i--){
   D[i] = A[i] + D[i + 1] * B[i];}
// Figure out our ends, so things start and end where they are
// supposed to.
D[0] = (P[1] - P[0])/3;
D[n] = (P[n] - P[n - 1])/3;

So.. This has more elements, so *may* allow someone to play more with 
the results, and produce a curve that gets "sloppy".

I just have two problems... The first one is that the A part has to be 
pre-computed for the path, so you can't "recompute" the thing on the 
fly. Catmull-rom had the advantage that, you could change the next point 
"on the fly", since it only computed between three points, and the 
computations didn't require, as above, that you first compute where your 
control points needed to be *then* computer the path *from* those. I.e., 
P is where you would like to be, A is the B-spline control points, and D 
is the actual path. Means, if I use this, I have to recompute any 
changes I make, as the bot moves between the computed points, which 
wastes more script time.

Now, Catmull I could tweak the curve, to some extent, by either adding a 
multiplier, i.e., adjusting the curve slightly over/under its normal 
size, but that just grows/shrinks the path, without changing the path. 
Picking some other random point, and using that for the next target, in 
the path, is also something vaguely possible, but I don't want this 
thing wandering through a wall, because the curve segment plotted sends 
it through one, and unless I pick "middle of the room" for every path 
point, I can't be sure that any point I pick won't be outside the room.

Basically, when this thing takes damage, I want it to start pathing 
erratically. Instead of following nice smooth paths between rooms, I 
want it to go a bit off-path, worse as it gets more and more damaged. 
And, while I would have preferred Catmull, due to the much simpler, and 
stepwise friendly, math it uses (the interpolated one is *not even 
close* in that regard), I figured maybe mucking with B in the above 
might produce the effect I wanted.

Any suggestions?

Mind, I can detect walls, by running into them, so, it just occurred to 
me that I could pick a random point within some value of the third one 
in the current path, then just "bump" the wall, and recompute with the 
next "correct" point, or the like. Need to experiment with that a bit.. 
Still.. Would be nice to have a clear idea what I am going to end up 
with first. I am not even sure, since the system doesn't have any 
indirect (I.e., not running into them first) way of finding walls yet, 
how to work out where such a bot should be "allowed" to fly, never mind 
mess with the path after. Closest I can manage now is to prefigure where 
all the points are it needs to know about, then compute "between" those 
preset points. Which is just annoying, since I have to then do that (or 
if I sell a version, provide someone else with a way to do so), for 
every single place I might want to put the thing in. It also presents 
problems for another design I wanted to do, which I might want to have 
coded to "Look for tight places, corners, the edge of walls, and keep 
away from people, but still close enough to see them." That's going to 
have to wait for them to implement the ray cast test, which will allow 
mapping of a space, though.

-- 
void main () {

     if version = "Vista" {
       call slow_by_half();
       call DRM_everything();
     }
     call functional_code();
   }
   else
     call crash_windows();
}

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