Drawing Shapes with Classes

Screenshot of Shapes example program
shapes.py
  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
"""
This simple animation example shows how to use classes to animate
multple objects on the screen at the same time.

Because this is redraws the shapes from scratch each frame, this is slow
and inefficient, but we'll show how to make it faster in the chapter on
performance.
"""

import arcade
import random

# Set up the constants
SCREEN_WIDTH = 800
SCREEN_HEIGHT = 600

RECT_WIDTH = 50
RECT_HEIGHT = 50


class Shape:

    def __init__(self, x, y, width, height, angle, delta_x, delta_y,
                 delta_angle, color):
        self.x = x
        self.y = y
        self.width = width
        self.height = height
        self.angle = angle
        self.delta_x = delta_x
        self.delta_y = delta_y
        self.delta_angle = delta_angle
        self.color = color

    def move(self):
        self.x += self.delta_x
        self.y += self.delta_y
        self.angle += self.delta_angle


class Ellipse(Shape):

    def draw(self):
        arcade.draw_ellipse_filled(self.x, self.y, self.width, self.height,
                                   self.color, self.angle)


class Rectangle(Shape):

    def draw(self):
        arcade.draw_rectangle_filled(self.x, self.y, self.width, self.height,
                                     self.color, self.angle)


class MyApplication(arcade.Window):
    """ Main application class. """

    def __init__(self):
        super().__init__(SCREEN_WIDTH, SCREEN_HEIGHT, title="Shapes!")
        self.shape_list = None

    def setup(self):
        """ Set up the game and initialize the variables. """
        self.shape_list = []

        for i in range(100):
            x = random.randrange(0, SCREEN_WIDTH)
            y = random.randrange(0, SCREEN_HEIGHT)
            width = random.randrange(10, 30)
            height = random.randrange(10, 30)
            angle = random.randrange(0, 360)

            d_x = random.randrange(-3, 4)
            d_y = random.randrange(-3, 4)
            d_angle = random.randrange(-3, 4)

            red = random.randrange(256)
            green = random.randrange(256)
            blue = random.randrange(256)
            alpha = random.randrange(256)

            shape_type = random.randrange(2)

            if shape_type == 0:
                shape = Rectangle(x, y, width, height, angle, d_x, d_y,
                                  d_angle, (red, green, blue, alpha))
            else:
                shape = Ellipse(x, y, width, height, angle, d_x, d_y,
                                d_angle, (red, green, blue, alpha))
            self.shape_list.append(shape)

    def update(self, dt):
        """ Move everything """

        for shape in self.shape_list:
            shape.move()

    def on_draw(self):
        """
        Render the screen.
        """
        arcade.start_render()

        for shape in self.shape_list:
            shape.draw()

window = MyApplication()
window.setup()

arcade.run()