Reference: drawSphere
drawSphere(r) draws a sphere of radius r > 0 and midpoint ❨0, 0, 0❩ in the current 3D visualisation window. drawSphere(v, r) draws a sphere of radius r > 0 and midpoint v ∈ R^3 in the current 3D visualisation window. drawSphere(v, r, s) draws a sphere of radius r > 0 and midpoint v ∈ R^3 in the current 3D visualisation window using the style (CSS) s, a string. Example: drawSphere(❨0, 0, 0❩, 5, "colour:red")