RubyFrac_test_04.rb

require 'tk'

$point_A = [0,0]
$point_B = [500,500]
$rate = 1.5

def before_drawing()
    $point_A = []
    temp_a = $point_B[0] / $rate
    temp_b = $point_B[1] / $rate
    $point_A << $point_B[0] - temp_a
    $point_A << $point_B[1] - temp_b
end

def after_drawing()
    $point_B = []
    $point_B << $point_A.[0]
    $point_B << $point_A.[1]
end

canvas = TkCanvas.new(:width=>750, :height=>750).pack('fill' => 'both', 'expand'=>true)

rect_1 = TkcRectangle.new(canvas, $point_A, $point_B)

before_drawing()
rect_2 = TkcRectangle.new(canvas, $point_A, $point_B)
after_drawing()

before_drawing()
rect_3 = TkcRectangle.new(canvas, $point_A, $point_B)
after_drawing()

before_drawing()
rect_4 = TkcRectangle.new(canvas, $point_A, $point_B)
after_drawing()

before_drawing()
rect_5 = TkcRectangle.new(canvas, $point_A, $point_B)

Tk.mainloop