Help on drawing a shape and slider

[Yoriz]

Okay perhaps I am not understanding something here but I have a basic issue with this as it appears to be a circular reference and even if it is not it is very confusing code.

scale = Scale(... command = mod_calc)

def mod_calc(w1) :
    slider_value = scale.get()

It appears your mod_calc is defined using scale and your scale is defined using mod_calc begging the question -- which comes first the chicken or the egg

mod_calc is an event handler function, it is called when the slider value changes.
scale has a reference to the scale widget, it is not a function, calling scale.get() is just using its get method.

it is not actually necessary to call scale.get() because the event passes the sliders value to the event handler function.

def mod_calc(w1) :
    slider_value = scale.get()

could be changed to

def mod_calc(w1) :
    slider_value = w1

or remove that line completely

def mod_calc(slider_value) :