from gpanel import *

import cmath

def cross(z,e=0.01):
    a = z.real
    b = z.imag
    line(a-e,b,a+e,b)
    line(a,b-e,a,b+e)
    
@onMouseClicked
def init(x,y):
    clear()
    # Koordinatensystem
    setColor("black");
    line(-4,0,4,0)
    line(0,-4,0,4)
    circle(0,0,1)

def myfunc(z):     
    return z*z*z

def show(z):
    setColor("black")
    cross(z)
    setColor("red")
    cross(myfunc(z))
    
@onMouseMoved
def mouseMoved(x,y):
    show(complex(x,y));

makeGPanel(-4, 4, -4, 4)
init(0,0)