$fn = 64;

// --- Parameters ---
cup_height = 60;          // Total height of the cup
cup_top_radius = 40;      // Outer radius at the top (80mm diameter)
cup_bottom_radius = 32;   // Outer radius at the base (64mm diameter)
wall_thickness = 2.5;     // Thickness of the walls
base_thickness = 3;       // Thickness of the bottom base
inner_fillet = 8;         // Radius of the inner rounded bottom (for easy scooping)

// --- Calculated Variables ---
inner_top_r = cup_top_radius - wall_thickness;
inner_bot_r = cup_bottom_radius - wall_thickness;

// --- Main Geometry ---
difference() {
    // Outer shell
    cylinder(h=cup_height, r1=cup_bottom_radius, r2=cup_top_radius);

    // Inner void (subtracted)
    hull() {
        // Top opening (extended slightly above to ensure a clean manifold cut)
        translate([0, 0, cup_height])
            cylinder(h=1, r=inner_top_r);

        // Bottom rounded corner (torus for smooth token scooping)
        translate([0, 0, base_thickness + inner_fillet])
            rotate_extrude()
                translate([inner_bot_r - inner_fillet, 0, 0])
                    circle(r=inner_fillet);

        // Fill the center flat area of the inner bottom
        translate([0, 0, base_thickness])
            cylinder(h=inner_fillet, r=inner_bot_r - inner_fillet);
    }
}