Shape List - Skylines

Screenshot of using shape list to create a moving skyline
shape_list_demo_skylines.py
  1"""
  2City Scape Generator
  3
  4If Python and Arcade are installed, this example can be run from the command line with:
  5python -m arcade.examples.shape_list_demo_skylines
  6"""
  7import random
  8import arcade
  9from arcade.shape_list import (
 10    ShapeElementList,
 11    create_rectangle_filled,
 12    create_polygon,
 13    create_rectangles_filled_with_colors,
 14)
 15
 16SCREEN_WIDTH = 1200
 17SCREEN_HEIGHT = 600
 18SCREEN_TITLE = "Skyline Using Buffered Shapes"
 19
 20
 21def make_star_field(star_count):
 22    """Make a bunch of circles for stars"""
 23    shape_list = ShapeElementList()
 24
 25    for _ in range(star_count):
 26        x = random.randrange(SCREEN_WIDTH)
 27        y = random.randrange(SCREEN_HEIGHT)
 28        radius = random.randrange(1, 4)
 29        brightness = random.randrange(127, 256)
 30        color = (brightness, brightness, brightness)
 31        shape = create_rectangle_filled(x, y, radius, radius, color)
 32        shape_list.append(shape)
 33
 34    return shape_list
 35
 36
 37def make_skyline(width, skyline_height, skyline_color,
 38                 gap_chance=0.70, window_chance=0.30, light_on_chance=0.5,
 39                 window_color=(255, 255, 200), window_margin=3, window_gap=2,
 40                 cap_chance=0.20):
 41    """Make a skyline of buildings"""
 42    shape_list = ShapeElementList()
 43
 44    # Add the "base" that we build the buildings on
 45    shape = create_rectangle_filled(width / 2, skyline_height / 2, width, skyline_height, skyline_color)
 46    shape_list.append(shape)
 47
 48    building_center_x = 0
 49
 50    skyline_point_list = []
 51    color_list = []
 52
 53    while building_center_x < width:
 54
 55        # Is there a gap between the buildings?
 56        if random.random() < gap_chance:
 57            gap_width = random.randrange(10, 50)
 58        else:
 59            gap_width = 0
 60
 61        # Figure out location and size of building
 62        building_width = random.randrange(20, 70)
 63        building_height = random.randrange(40, 150)
 64        building_center_x += gap_width + (building_width / 2)
 65        building_center_y = skyline_height + (building_height / 2)
 66
 67        x1 = building_center_x - building_width / 2
 68        x2 = building_center_x + building_width / 2
 69        y1 = skyline_height
 70        y2 = skyline_height + building_height
 71
 72        skyline_point_list.append([x1, y1])
 73        skyline_point_list.append([x1, y2])
 74        skyline_point_list.append([x2, y2])
 75        skyline_point_list.append([x2, y1])
 76
 77        for i in range(4):
 78            color_list.append([skyline_color[0], skyline_color[1], skyline_color[2]])
 79
 80        if random.random() < cap_chance:
 81            x1 = building_center_x - building_width / 2
 82            x2 = building_center_x + building_width / 2
 83            x3 = building_center_x
 84
 85            y1 = y2 = building_center_y + building_height / 2
 86            y3 = y1 + building_width / 2
 87
 88            # Roof
 89            shape = create_polygon([[x1, y1], [x2, y2], [x3, y3]], skyline_color)
 90            shape_list.append(shape)
 91
 92        # See if we should have some windows
 93        if random.random() < window_chance:
 94            # Yes windows! How many windows?
 95            window_rows = random.randrange(10, 15)
 96            window_columns = random.randrange(1, 7)
 97
 98            # Based on that, how big should they be?
 99            window_height = (building_height - window_margin * 2) / window_rows
100            window_width = (building_width - window_margin * 2 - window_gap * (window_columns - 1)) / window_columns
101
102            # Find the bottom left of the building so we can start adding widows
103            building_base_y = building_center_y - building_height / 2
104            building_left_x = building_center_x - building_width / 2
105
106            # Loop through each window
107            for row in range(window_rows):
108                for column in range(window_columns):
109                    if random.random() < light_on_chance:
110                        x1 = building_left_x + column * (window_width + window_gap) + window_margin
111                        x2 = building_left_x + column * (window_width + window_gap) + window_width + window_margin
112                        y1 = building_base_y + row * window_height
113                        y2 = building_base_y + row * window_height + window_height * .8
114
115                        skyline_point_list.append([x1, y1])
116                        skyline_point_list.append([x1, y2])
117                        skyline_point_list.append([x2, y2])
118                        skyline_point_list.append([x2, y1])
119
120                        for i in range(4):
121                            color_list.append((window_color[0], window_color[1], window_color[2]))
122
123        building_center_x += (building_width / 2)
124
125    shape = create_rectangles_filled_with_colors(skyline_point_list, color_list)
126    shape_list.append(shape)
127
128    return shape_list
129
130
131class MyGame(arcade.Window):
132    """ Main application class. """
133
134    def __init__(self):
135        """ Initializer """
136        # Call the parent class initializer
137        super().__init__(SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_TITLE)
138        # Enable vertical sync to make scrolling smoother
139        self.set_vsync(True)
140
141        self.stars = make_star_field(150)
142        self.skyline1 = make_skyline(SCREEN_WIDTH * 5, 250, (80, 80, 80))
143        self.skyline2 = make_skyline(SCREEN_WIDTH * 5, 150, (50, 50, 50))
144
145        self.background_color = arcade.color.BLACK
146
147    def on_draw(self):
148        """Draw to screen"""
149        self.clear()
150
151        self.stars.draw()
152        self.skyline1.draw()
153        self.skyline2.draw()
154
155    def on_update(self, delta_time):
156        """Per frame update logic"""
157        # Scroll each shape list with a slight offset to give a parallax effect
158        self.skyline1.center_x -= 0.5 * 60 * delta_time
159        self.skyline2.center_x -= 1 * 60 * delta_time
160
161    def on_mouse_drag(self, x: int, y: int, dx: int, dy: int, buttons: int, modifiers: int):
162        """Make it possible scroll the scene around by dragging the mouse"""
163        self.skyline1.center_x += dx
164        self.skyline1.center_y += dy
165
166        self.skyline2.center_x += dx
167        self.skyline2.center_y += dy
168
169
170def main():
171    window = MyGame()
172    window.run()
173
174
175if __name__ == "__main__":
176    main()