$fn=64;

// --- Parameters ---
tile_size = 40;            // Width and length of the square tile
tile_height = 4;           // Total height of the tile
road_width = 20;           // Width of the straight road section
road_depth = 1.5;          // Depth of the road surface from the top
cul_de_sac_radius = 14;    // Radius of the round turnaround
cul_de_sac_y = 3;          // Y-axis center point for the turnaround

module dead_end_tile() {
    difference() {
        // Main base tile
        translate([-tile_size/2, -tile_size/2, 0])
            cube([tile_size, tile_size, tile_height]);
        
        // Subtract road and cul-de-sac geometry
        union() {
            // Straight road entrance (extended slightly to ensure clean cut)
            translate([-road_width/2, -tile_size/2 - 1, tile_height - road_depth])
                cube([road_width, tile_size/2 + cul_de_sac_y + 1, road_depth + 1]);
            
            // Round cul-de-sac turnaround
            translate([0, cul_de_sac_y, tile_height - road_depth])
                cylinder(r=cul_de_sac_radius, h=road_depth + 1);
        }
    }
    
    // Add raised center dividing line
    translate([-0.75, -19, tile_height - road_depth])
        cube([1.5, 10, 0.4]);
}

dead_end_tile();