Thomas de Groot <tho### [at] degrootorg> wrote:

> > I was wondering what your "yield" was in terms of successful placement of random
> > points inside.  I did a few real quick experiments, and it seemed like I was
> > getting _very_ sparse coverage.  I did a (Success/TotalTests)*100 calculation,
> > and got 1.4%.
>
> I don't know about yield. Using VRand_In_Obj() that should be 100%,
> shouldn't it? Anyway, I just increase or decrease the number of objects
> and judge the result.

Yes, I was just testing a vector in the bounding box.
IIRC VRand_In_Object() is part of an iclude file, so it just does pretty much
the same thing - the success/fail process is just hidden.

> My main focus now is to get a "better" (?) coverage of the arms and legs
> compared to the body. They seem to be more sparsely populated. So, my
> idea was to use an additional test: function {pow(f_boxed(x,y,z),2)}
> provided by Christian Froeschlin some years ago, and thus concentrate
> the objects more towards the periphery than towards the centre. However,
> I am not sure what I am doing and I have difficulty scaling this to the
> correct proportions of the body. Any suggestions there would help me.

Right - I noticed the same problem.
I thought about that and naturally what Stephen suggested is the most obvious
solution.
Your function-based approach is something that could work, though I was thinking
of something more cylindrical / spherical / egg-shaped and centered on the body
trunk.

Alternatively, you could use an x-y-z nested loop of smaller testing boxes and
cycle through a random placement in all of those smaller boxes.

It would, of course, be VERY nice if someone in-the-know could hammer out some
sort of octree macro/include file that made some sense to those of us who
haven't had the time to puzzle all of that out yet.

Along those lines, you could build an array to store coordinates, "scan" the
bounding box of the figure with an x-y-z nested loop and inside(object, vector)
tests, and then use the pseudorandom selection process to pick known inside()
points.
The advantage there is that you could save the array to disk, and not have to
test the same figure every single time you wanted to place objects.  You
wouldn't even need to load the mesh for the figure either.

So far, my whole weekend has been major SNAFU, so I haven't had mush time to
fiddle with many of the things I've wanted to.  :(

Hopefully the rest of the week/weekend won't be FUBAR.

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