$fn = 64;

// --- PARAMETERS ---

// Grid dimensions
cols = 3;
rows = 4;

// Dimensions per grid unit
unit_size = 25;
thickness = 6;

// Connection point (hole) dimensions
hole_dia = 5;
hole_depth = 4;

// Interlocking dovetail tab dimensions
tab_base = 8;
tab_tip = 12;
tab_length = 5;
tolerance = 0.2; // Clearance for easy assembly

// --- MODULES ---

module male_tab() {
    linear_extrude(height = thickness)
    polygon([
        [-tab_base/2, 0],
        [-tab_tip/2, tab_length],
        [tab_tip/2, tab_length],
        [tab_base/2, 0]
    ]);
}

module female_cutout() {
    translate([0, 0, -0.1])
    linear_extrude(height = thickness + 0.2)
    polygon([
        [-(tab_base/2 + tolerance), -0.1], // Extend slightly to prevent manifold slivers
        [-(tab_tip/2 + tolerance), tab_length + tolerance],
        [(tab_tip/2 + tolerance), tab_length + tolerance],
        [(tab_base/2 + tolerance), -0.1]
    ]);
}

module figure_stage_baseplate() {
    difference() {
        union() {
            // Main platform body
            cube([cols * unit_size, rows * unit_size, thickness]);
            
            // Male tabs on Right edge (X+)
            for (y = [0 : rows - 1]) {
                translate([cols * unit_size, (y + 0.5) * unit_size, 0])
                rotate([0, 0, -90])
                male_tab();
            }
            
            // Male tabs on Top edge (Y+)
            for (x = [0 : cols - 1]) {
                translate([(x + 0.5) * unit_size, rows * unit_size, 0])
                rotate([0, 0, 0])
                male_tab();
            }
        }
        
        // Female cutouts on Left edge (X-)
        for (y = [0 : rows - 1]) {
            translate([0, (y + 0.5) * unit_size, 0])
            rotate([0, 0, -90])
            female_cutout();
        }
        
        // Female cutouts on Bottom edge (Y-)
        for (x = [0 : cols - 1]) {
            translate([(x + 0.5) * unit_size, 0, 0])
            rotate([0, 0, 0])
            female_cutout();
        }
        
        // Grid connection holes
        for (x = [0 : cols - 1]) {
            for (y = [0 : rows - 1]) {
                translate([(x + 0.5) * unit_size, (y + 0.5) * unit_size, thickness - hole_depth])
                cylinder(d = hole_dia, h = hole_depth + 0.1);
            }
        }
    }
}

// --- RENDER ---
figure_stage_baseplate();