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Re: Arbitrary aligned box or plane
Oh, ding it -- I thought pack's packers (regularHexa etc) were returning
SpherePack instances, but in reality they return list of bodies already
(I should know, since it is my code, sorry)!
Well, use pack.regularHexa(...) with pack.inAlignedBox. Is there a way to
create such packings with pack.SpherePack()? Or how can I convert it in a
SpherePack()? I tried to pass the regularHexa packing to the SpherePack,
dosen't work. If this is going to work somehow it would be enough for my
Now, I think it would be more logical for them to return SpherePack's,
since they are just centers+positions, what one would expect (perhaps
there are some issues why I decided to return bodies directly that I
don't see now), and then one might to call SpherePack.toSimulation() to
add them to O.bodies (or a similar function). (I would add some
additional argument, to make it backwards-compatible for some time, so
that old code would work as it did and give warning about future break).
Are you using trunk? Would it be useful for you?
Meanwhile, you can change spheres' positions by hand in a loop, like this:
from yade import pack
# define around which point to rotate, and the rotation itself
# apply to all spheres in the packing
for b in hexapack: b.state.pos=p0+rot*(b.state.pos-p0)
# add to the simulation (it does not matter if you add particles to
simulation first or rotate them first, really)
The two have orthogonal meanings. Packers defines the pattern (texture,
sphere configuration, ... -- however you would like to call it) whereas
predicate defines the volume where it will be created. E.g. hexagonal
packer will create hexagonal configuration in volume given by
inAlignedBox, but it can be created in a cylinder, in a volume defined
as intersection of box with sphere, and so on.
The reason I did not create general box orientation is that checking
whether particle is inside or outside is more complicated; but now I
have the idea that it could be actually done by keeping corners and box
transformation in the predicate, then transforming points to be checked,
rather than checking points against true (non-aligned) boundaries.
Hm, I am a newbie and I still have to understand the difference between the two
packing options. By the way, what's the difference? Can't you just use
(That makes me think that I could also add something like inHalfSpace
(oriented clipping plane) predicate, then you could create e.g. box and
clip it by 2 arbitrary planes from each side; or define a box-like
volume with 6 of such planes.)
Probably not directly (though you could create a thin volume for
instance). Can you be more specific as to what usage you have in mind?
Thin volume works fine.