Using a Vertex Buffer Object With Lines

Screen shot of a maze created by depth first
lines_buffered.py
 1"""
 2Using a Vertex Buffer Object With Lines
 3
 4If Python and Arcade are installed, this example can be run from the command line with:
 5python -m arcade.examples.lines_buffered
 6"""
 7import random
 8import arcade
 9from arcade.shape_list import (
10    ShapeElementList,
11    create_line_strip,
12)
13from inspect import getmembers
14from arcade.types import Color
15
16# Do the math to figure out our screen dimensions
17WINDOW_WIDTH = 1280
18WINDOW_HEIGHT = 720
19WINDOW_TITLE = "Vertex Buffer Object With Lines Example"
20
21
22class GameView(arcade.View):
23    """
24    Main application class.
25    """
26
27    def __init__(self):
28        """
29        Set up the application.
30        """
31        super().__init__()
32
33        self.shape_list = ShapeElementList()
34        point_list = ((0, 50),
35                      (10, 10),
36                      (50, 0),
37                      (10, -10),
38                      (0, -50),
39                      (-10, -10),
40                      (-50, 0),
41                      (-10, 10),
42                      (0, 50))
43
44        # Filter out anything other than a Color, such as imports and
45        # helper functions.
46        colors = [
47            color for name, color in
48            getmembers(arcade.color, lambda c: isinstance(c, Color))]
49
50        for i in range(200):
51            x = WINDOW_WIDTH // 2 - random.randrange(WINDOW_WIDTH)
52            y = WINDOW_HEIGHT // 2 - random.randrange(WINDOW_HEIGHT)
53            color = random.choice(colors)
54            points = [(px + x, py + y) for px, py in point_list]
55
56            my_line_strip = create_line_strip(points, color, 5)
57            self.shape_list.append(my_line_strip)
58
59        self.shape_list.center_x = WINDOW_WIDTH // 2
60        self.shape_list.center_y = WINDOW_HEIGHT // 2
61        self.shape_list.angle = 0
62
63        self.background_color = arcade.color.BLACK
64
65    def on_draw(self):
66        """
67        Render the screen.
68        """
69        # This command has to happen before we start drawing
70        self.clear()
71
72        self.shape_list.draw()
73
74    def on_update(self, delta_time):
75        self.shape_list.angle += 1 * 60 * delta_time
76        self.shape_list.center_x += 0.1 * 60 * delta_time
77        self.shape_list.center_y += 0.1 * 60 * delta_time
78
79
80def main():
81    """ Main function """
82    # Create a window class. This is what actually shows up on screen
83    window = arcade.Window(WINDOW_WIDTH, WINDOW_HEIGHT, WINDOW_TITLE, vsync=True)
84
85    # Create and setup the GameView
86    game = GameView()
87
88    # Show GameView on screen
89    window.show_view(game)
90
91    # Start the arcade game loop
92    arcade.run()
93
94
95if __name__ == "__main__":
96    main()