Grid generator script for producing unionized grid meshes from an STL file and gap pad meshes

grid-generator.scad

// Generates a grid of body meshes with pad meshes between them.
// "Fence-post" pattern: N bodies get N-1 pads between them.
//
// STL files must be in the same directory as this script,
// or provide absolute paths.
//
// Pad STLs should have their geometry positioned in object-local
// coordinates so that when placed at the same grid points as the
// bodies, they naturally align into the gaps:
//   - h_pad.stl: offset to bridge the horizontal gap
//   - v_pad.stl: offset to bridge the vertical gap
//   - gap_pad.stl: offset to fit into the interior corner where
//     4 bodies meet (bottom-right corner of the grid point body)

/* [Grid Parameters] */

// Number of bodies horizontally (X direction)
body_count_x = 3;

// Number of bodies vertically (Y direction)
body_count_y = 2;

// Horizontal spacing between body placement points (mm)
horizontal_offset = 42;

// Vertical spacing between body placement points (mm)
vertical_offset = 42;

/* [STL File Paths] */

// Body mesh STL file
body_stl = "body.stl";

// Horizontal pad mesh STL file
h_pad_stl = "h_pad.stl";

// Vertical pad mesh STL file
v_pad_stl = "v_pad.stl";

// Gap pad mesh STL file — fills interior corners where 4 bodies meet
gap_pad_stl = "gap_pad.stl";

/* [Hidden] */

module at_grid(x, y) {
    translate([x * horizontal_offset, y * vertical_offset, 0])
        children();
}

// ========================
// MAIN RENDERING
// ========================

// Bodies: full grid
for (x = [0 : body_count_x - 1]) {
    for (y = [0 : body_count_y - 1]) {
        at_grid(x, y)
            import(body_stl);
    }
}

// Horizontal pads: (body_count_x - 1) x body_count_y
if (body_count_x > 1) {
    for (x = [0 : body_count_x - 2]) {
        for (y = [0 : body_count_y - 1]) {
            at_grid(x, y)
                import(h_pad_stl);
        }
    }
}

// Vertical pads: body_count_x x (body_count_y - 1)
if (body_count_y > 1) {
    for (x = [0 : body_count_x - 1]) {
        for (y = [0 : body_count_y - 2]) {
            at_grid(x, y)
                import(v_pad_stl);
        }
    }
}

// Gap pads: (body_count_x - 1) x (body_count_y - 1)
// Fence-post in both axes — fills interior corners where 4 bodies meet.
// Placed at (1..cx-1, 0..cy-2) since the gap pad's local geometry
// extends in -X and +Y from its placement point.
if (body_count_x > 1 && body_count_y > 1) {
    for (x = [1 : body_count_x - 1]) {
        for (y = [0 : body_count_y - 2]) {
            at_grid(x, y)
                import(gap_pad_stl);
        }
    }
}