$fn = 64;

// --- Parameters ---
pot_diameter = 100;       // Inner diameter to fit the pot
clearance = 2;            // Extra space to easily slide over the pot
fence_height = 70;        // Total height of the pickets
picket_width = 12;        // Width of each individual picket
picket_thickness = 3;     // Thickness of the pickets
rail_height = 6;          // Height of the horizontal connecting bands
rail_thickness = 2.5;     // Thickness of the horizontal bands
num_pickets = 22;         // Total number of pickets around the ring

// --- Derived Variables ---
inner_r = (pot_diameter + clearance) / 2;

// --- Modules ---

// Single picket generator
module picket(w, h, t) {
    union() {
        // Main rectangular body
        translate([0, -w/2, 0])
            cube([t, w, h - w/2]);
            
        // Pointed top
        hull() {
            translate([0, -w/2, h - w/2 - 0.01])
                cube([t, w, 0.01]);
            translate([0, -0.01, h - 0.01])
                cube([t, 0.02, 0.01]);
        }
    }
}

// Main fence ring assembly
module fence_ring() {
    union() {
        // Bottom Rail
        translate([0, 0, fence_height * 0.15])
            difference() {
                cylinder(r = inner_r + rail_thickness, h = rail_height);
                translate([0, 0, -1])
                    cylinder(r = inner_r, h = rail_height + 2);
            }

        // Top Rail
        translate([0, 0, fence_height * 0.65])
            difference() {
                cylinder(r = inner_r + rail_thickness, h = rail_height);
                translate([0, 0, -1])
                    cylinder(r = inner_r, h = rail_height + 2);
            }

        // Pickets
        for (i = [0 : num_pickets - 1]) {
            rotate([0, 0, i * 360 / num_pickets])
                // Overlap by 0.5mm into the rail to ensure a manifold mesh
                translate([inner_r + rail_thickness - 0.5, 0, 0])
                    picket(picket_width, fence_height, picket_thickness);
        }
    }
}

// --- Render ---
fence_ring();