// Bee Hotel - a hexagonal nesting block for solitary bees (mason and leafcutter bees): a honeycomb of blind 8 mm
// tubes with a closed back, a roof that sticks out over the top, and a hanging tab.
// Prints lying on its back with no supports: the tubes are straight up and the roof is just taller walls.
// Designed with AI assistance. License: CC BY-NC-SA 4.0

/* [Hotel] */
// Size across the corners, in mm
size = 100;           // [80:5:180]
// Tube depth, in mm (mason bees like 100 mm or more)
depth = 80;           // [50:5:150]
// Tube size across the flats, in mm (7-8 for mason bees, 6 for smaller bees)
cell = 8;             // [5:0.5:10]
// Wall between tubes, in mm
cell_wall = 1;        // [0.8:0.1:2]
// How far the roof sticks out, in mm
roof = 12;            // [0:1:30]

/* [Hidden] */
R = size / 2; fw = 4; back = 3;
module hex(r) rotate(90) circle(r = r, $fn = 6);      // a corner at the top (the roof ridge)
module cells2d() {
    p = cell + cell_wall; dy = p * sqrt(3) / 2; rc = cell / sqrt(3);
    intersection() {
        hex(R - fw - 0.01);
        difference() {
            hex(R - fw);
            for (j = [-ceil(R / dy) : ceil(R / dy)], i = [-ceil(R / p) - 1 : ceil(R / p) + 1])
                translate([i * p + (abs(j) % 2) * p / 2, j * dy]) circle(r = rc, $fn = 6);
        }
    }
}
union() {
    linear_extrude(depth + back) difference() { hex(R); hex(R - fw); }
    linear_extrude(back) hex(R - fw + 0.01);
    translate([0, 0, back - 0.01]) linear_extrude(depth + 0.01) cells2d();
    // the roof: the two top walls run on past the front
    linear_extrude(depth + back + roof) intersection() { difference() { hex(R); hex(R - fw); } translate([-R, R / 2 - 0.01]) square([2 * R, R]); }
    // hanging tab above the top corner, flat on the bed
    difference() {
        hull() { translate([0, R - 6]) cylinder(r = 10, h = 4, $fn = 48); translate([0, R + 6]) cylinder(r = 10, h = 4, $fn = 48); }
        translate([0, R + 7, -1]) cylinder(d = 7, h = 10, $fn = 32);
    }
}