BOSL2/partitions.scad

187 lines
8.9 KiB
OpenSCAD

//////////////////////////////////////////////////////////////////////
// LibFile: partitions.scad
// Modules to help partition large objects into smaller parts that can be reassembled.
// To use, add the following lines to the beginning of your file:
// ```
// include <BOSL2/std.scad>
// include <BOSL2/partitions.scad>
// ```
//////////////////////////////////////////////////////////////////////
// Section: Partitioning
_partition_cutpaths = [
["flat", [[0,0],[1,0]]],
["sawtooth", [[0,-0.5], [0.5,0.5], [1,-0.5]]],
["sinewave", [for (a=[0:5:360]) [a/360,sin(a)/2]]],
["comb", let(dx=0.5*sin(2)) [[0,0],[0+dx,0.5],[0.5-dx,0.5],[0.5+dx,-0.5],[1-dx,-0.5],[1,0]]],
["finger", let(dx=0.5*sin(20)) [[0,0],[0+dx,0.5],[0.5-dx,0.5],[0.5+dx,-0.5],[1-dx,-0.5],[1,0]]],
["dovetail", [[0,-0.5], [0.3,-0.5], [0.2,0.5], [0.8,0.5], [0.7,-0.5], [1,-0.5]]],
["hammerhead", [[0,-0.5], [0.35,-0.5], [0.35,0], [0.15,0], [0.15,0.5], [0.85,0.5], [0.85,0], [0.65,0], [0.65,-0.5],[1,-0.5]]],
["jigsaw", concat(
arc(N=6, r=5/16, cp=[0,-3/16], start=270, angle=125),
arc(N=12, r=5/16, cp=[1/2,3/16], start=215, angle=-250),
arc(N=6, r=5/16, cp=[1,-3/16], start=145, angle=125)
)
],
];
function _partition_cutpath(l, h, cutsize, cutpath, gap) =
let(
check = assert(is_finite(l))
assert(is_finite(h))
assert(is_finite(gap))
assert(is_finite(cutsize) || is_vector(cutsize,2))
assert(is_string(cutpath) || is_path(cutpath,2)),
cutsize = is_vector(cutsize)? cutsize : [cutsize*2, cutsize],
cutpath = is_path(cutpath)? cutpath : (
let(idx = search([cutpath], _partition_cutpaths))
idx==[[]]? assert(in_list(cutpath,_partition_cutpaths,idx=0)) :
_partition_cutpaths[idx.x][1]
),
reps = ceil(l/(cutsize.x+gap)),
cplen = (cutsize.x+gap) * reps,
path = deduplicate(concat(
[[-l/2, cutpath[0].y*cutsize.y]],
[for (i=[0:1:reps-1], pt=cutpath) vmul(pt,cutsize)+[i*(cutsize.x+gap)+gap/2-cplen/2,0]],
[[ l/2, cutpath[len(cutpath)-1].y*cutsize.y]]
))
) path;
// Module: partition_mask()
// Usage:
// partition_mask(l, w, h, [cutsize], [cutpath], [gap], [inverse], [spin], [orient]);
// Description:
// Creates a mask that you can use to difference or intersect with an object to remove half of it, leaving behind a side designed to allow assembly of the sub-parts.
// Arguments:
// l = The length of the cut axis.
// w = The width of the part to be masked, back from the cut plane.
// h = The height of the part to be masked.
// cutsize = The width of the cut pattern to be used.
// cutpath = The cutpath to use. Standard named paths are "flat", "sawtooth", "sinewave", "comb", "finger", "dovetail", "hammerhead", and "jigsaw". Alternatively, you can give a cutpath as a 2D path, where X is between 0 and 1, and Y is between -0.5 and 0.5.
// gap = Empty gaps between cutpath iterations. Default: 0
// inverse = If true, create a cutpath that is meant to mate to a non-inverted cutpath.
// spin = Rotate this many degrees around the Z axis. See [spin](attachments.scad#spin). Default: `0`
// orient = Vector to rotate top towards. See [orient](attachments.scad#orient). Default: `UP`
// Examples:
// partition_mask(w=50, gap=0, cutpath="jigsaw");
// partition_mask(w=50, gap=30, cutpath="jigsaw");
// partition_mask(w=50, gap=30, cutpath="jigsaw", inverse=true);
// partition_mask(w=50, gap=30, cutsize=15, cutpath="jigsaw");
// partition_mask(w=50, cutsize=[20,20], gap=30, cutpath="jigsaw");
// Examples(2D):
// partition_mask(w=20, cutpath="sawtooth");
// partition_mask(w=20, cutpath="sinewave");
// partition_mask(w=20, cutpath="comb");
// partition_mask(w=20, cutpath="finger");
// partition_mask(w=20, cutpath="dovetail");
// partition_mask(w=20, cutpath="hammerhead");
// partition_mask(w=20, cutpath="jigsaw");
module partition_mask(l=100, w=100, h=100, cutsize=10, cutpath=undef, gap=0, inverse=false, spin=0, orient=UP)
{
cutsize = is_vector(cutsize)? point2d(cutsize) : [cutsize*2, cutsize];
path = _partition_cutpath(l, h, cutsize, cutpath, gap);
fullpath = concat(path, [[l/2,w*(inverse?-1:1)], [-l/2,w*(inverse?-1:1)]]);
rot(from=UP,to=orient) {
rotate(spin) {
linear_extrude(height=h, convexity=10) {
offset(delta=-$slop) polygon(fullpath);
}
}
}
}
// Module: partition_cut_mask()
// Usage:
// partition_cut_mask(l, w, h, [cutsize], [cutpath], [gap], [inverse], [spin], [orient]);
// Description:
// Creates a mask that you can use to difference with an object to cut it into two sub-parts that can be assembled.
// Arguments:
// l = The length of the cut axis.
// w = The width of the part to be masked, back from the cut plane.
// h = The height of the part to be masked.
// cutsize = The width of the cut pattern to be used.
// cutpath = The cutpath to use. Standard named paths are "flat", "sawtooth", "sinewave", "comb", "finger", "dovetail", "hammerhead", and "jigsaw". Alternatively, you can give a cutpath as a 2D path, where X is between 0 and 1, and Y is between -0.5 and 0.5.
// gap = Empty gaps between cutpath iterations. Default: 0
// spin = Rotate this many degrees around the Z axis. See [spin](attachments.scad#spin). Default: `0`
// orient = Vector to rotate top towards. See [orient](attachments.scad#orient). Default: `UP`
// Examples:
// partition_cut_mask(gap=0, cutpath="dovetail");
// partition_cut_mask(gap=30, cutpath="dovetail");
// partition_cut_mask(gap=30, cutsize=15, cutpath="dovetail");
// partition_cut_mask(gap=30, cutsize=[20,20], cutpath="dovetail");
// Examples(2DMed):
// partition_cut_mask(cutpath="sawtooth");
// partition_cut_mask(cutpath="sinewave");
// partition_cut_mask(cutpath="comb");
// partition_cut_mask(cutpath="finger");
// partition_cut_mask(cutpath="dovetail");
// partition_cut_mask(cutpath="hammerhead");
// partition_cut_mask(cutpath="jigsaw");
module partition_cut_mask(l=100, h=100, cutsize=10, cutpath=undef, gap=0, spin=0, orient=UP)
{
cutsize = is_vector(cutsize)? cutsize : [cutsize*2, cutsize];
path = _partition_cutpath(l, h, cutsize, cutpath, gap);
rot(from=UP,to=orient) {
rotate(spin) {
linear_extrude(height=h, convexity=10) {
stroke(path, width=$slop*2);
}
}
}
}
// Module: partition()
// Usage:
// partition(size, [spread], [cutsize], [cutpath], [gap], [spin]) ...
// Description:
// Partitions an object into two parts, spread apart a small distance, with matched joining edges.
// Arguments:
// size = The [X,Y,Z] size of the object to partition.
// spread = The distance to spread the two parts by.
// cutsize = The width of the cut pattern to be used.
// cutpath = The cutpath to use. Standard named paths are "flat", "sawtooth", "sinewave", "comb", "finger", "dovetail", "hammerhead", and "jigsaw". Alternatively, you can give a cutpath as a 2D path, where X is between 0 and 1, and Y is between -0.5 and 0.5.
// gap = Empty gaps between cutpath iterations. Default: 0
// spin = Rotate this many degrees around the Z axis. See [spin](attachments.scad#spin). Default: `0`
// Examples(Med):
// partition(spread=12, cutpath="dovetail") cylinder(h=50, d=80, center=false);
// partition(spread=12, gap=30, cutpath="dovetail") cylinder(h=50, d=80, center=false);
// partition(spread=20, gap=20, cutsize=15, cutpath="dovetail") cylinder(h=50, d=80, center=false);
// partition(spread=25, gap=15, cutsize=[20,20], cutpath="dovetail") cylinder(h=50, d=80, center=false);
// Examples(2DMed):
// partition(cutpath="sawtooth") cylinder(h=50, d=80, center=false);
// partition(cutpath="sinewave") cylinder(h=50, d=80, center=false);
// partition(cutpath="comb") cylinder(h=50, d=80, center=false);
// partition(cutpath="finger") cylinder(h=50, d=80, center=false);
// partition(spread=12, cutpath="dovetail") cylinder(h=50, d=80, center=false);
// partition(spread=12, cutpath="hammerhead") cylinder(h=50, d=80, center=false);
// partition(cutpath="jigsaw") cylinder(h=50, d=80, center=false);
module partition(size=100, spread=10, cutsize=10, cutpath=undef, gap=0, spin=0)
{
size = is_vector(size)? size : [size,size,size];
cutsize = is_vector(cutsize)? cutsize : [cutsize*2, cutsize];
rsize = vabs(rot(spin,p=size));
vec = rot(spin,p=BACK)*spread/2;
move(vec) {
intersection() {
children();
partition_mask(l=rsize.x, w=rsize.y, h=rsize.z, cutsize=cutsize, cutpath=cutpath, gap=gap, spin=spin);
}
}
move(-vec) {
intersection() {
children();
partition_mask(l=rsize.x, w=rsize.y, h=rsize.z, cutsize=cutsize, cutpath=cutpath, gap=gap, inverse=true, spin=spin);
}
}
}
// vim: expandtab tabstop=4 shiftwidth=4 softtabstop=4 nowrap