Grid Using Sprites v1#

Screenshot of a program that shows an array backed grid.

You may also want to look at:

array_backed_grid_sprites_1.py#
  1"""
  2Array Backed Grid Shown By Sprites
  3
  4Show how to use a two-dimensional list/array to back the display of a
  5grid on-screen.
  6
  7This version syncs the grid to the sprite list in one go using resync_grid_with_sprites.
  8This is faster than rebuilding a shape list every time the grid changes,
  9but we are still inspecting every single cell of the grid when it updates.
 10There are faster ways, but this works for smaller grid sizes.
 11
 12If Python and Arcade are installed, this example can be run from the command line with:
 13python -m arcade.examples.array_backed_grid_sprites_1
 14"""
 15import arcade
 16
 17# Set how many rows and columns we will have
 18ROW_COUNT = 15
 19COLUMN_COUNT = 15
 20
 21# This sets the WIDTH and HEIGHT of each grid location
 22WIDTH = 30
 23HEIGHT = 30
 24
 25# This sets the margin between each cell
 26# and on the edges of the screen.
 27MARGIN = 5
 28
 29# Do the math to figure out our screen dimensions
 30SCREEN_WIDTH = (WIDTH + MARGIN) * COLUMN_COUNT + MARGIN
 31SCREEN_HEIGHT = (HEIGHT + MARGIN) * ROW_COUNT + MARGIN
 32SCREEN_TITLE = "Array Backed Grid Example"
 33
 34
 35class MyGame(arcade.Window):
 36    """
 37    Main application class.
 38    """
 39
 40    def __init__(self, width, height, title):
 41        """
 42        Set up the application.
 43        """
 44        super().__init__(width, height, title)
 45
 46        # Create a 2 dimensional array. A two dimensional
 47        # array is simply a list of lists.
 48        # This array can be altered later to contain 0 or 1
 49        # to show a white or green cell.
 50        #
 51        # A 4 x 4 grid would look like this
 52        #
 53        # grid = [
 54        #     [0, 0, 0, 0],
 55        #     [0, 0, 0, 0],
 56        #     [0, 0, 0, 0],
 57        #     [0, 0, 0, 0],
 58        # ]
 59        # We can quickly build a grid with python list comprehension
 60        # self.grid = [[0] * COLUMN_COUNT for _ in range(ROW_COUNT)]
 61        # Making the grid with loops:
 62        self.grid = []
 63        for row in range(ROW_COUNT):
 64            # Add an empty array that will hold each cell
 65            # in this row
 66            self.grid.append([])
 67            for column in range(COLUMN_COUNT):
 68                self.grid[row].append(0)  # Append a cell
 69
 70        # Set the window's background color
 71        self.background_color = arcade.color.BLACK
 72        # Create a spritelist for batch drawing all the grid sprites
 73        self.grid_sprite_list = arcade.SpriteList()
 74
 75        # Create a list of solid-color sprites to represent each grid location
 76        for row in range(ROW_COUNT):
 77            for column in range(COLUMN_COUNT):
 78                x = column * (WIDTH + MARGIN) + (WIDTH / 2 + MARGIN)
 79                y = row * (HEIGHT + MARGIN) + (HEIGHT / 2 + MARGIN)
 80                sprite = arcade.SpriteSolidColor(WIDTH, HEIGHT, color=arcade.color.WHITE)
 81                sprite.center_x = x
 82                sprite.center_y = y
 83                self.grid_sprite_list.append(sprite)
 84
 85    def resync_grid_with_sprites(self):
 86        """
 87        Update the color of all the sprites to match
 88        the color/stats in the grid.
 89
 90        We look at the values in each cell.
 91        If the cell contains 0 we assign a white color.
 92        If the cell contains 1 we assign a green color.
 93        """
 94        for row in range(ROW_COUNT):
 95            for column in range(COLUMN_COUNT):
 96                # We need to convert our two dimensional grid to our
 97                # one-dimensional sprite list. For example a 10x10 grid might have
 98                # row 2, column 8 mapped to location 28. (Zero-basing throws things
 99                # off, but you get the idea.)
100                # ALTERNATIVELY you could set self.grid_sprite_list[pos].texture
101                # to different textures to change the image instead of the color.
102                pos = row * COLUMN_COUNT + column
103                if self.grid[row][column] == 0:
104                    self.grid_sprite_list[pos].color = arcade.color.WHITE
105                else:
106                    self.grid_sprite_list[pos].color = arcade.color.GREEN
107
108    def on_draw(self):
109        """
110        Render the screen.
111        """
112        # We should always start by clearing the window pixels
113        self.clear()
114
115        # Batch draw all the sprites
116        self.grid_sprite_list.draw()
117
118    def on_mouse_press(self, x, y, button, modifiers):
119        """
120        Called when the user presses a mouse button.
121        """
122
123        # Convert the clicked mouse position into grid coordinates
124        column = int(x // (WIDTH + MARGIN))
125        row = int(y // (HEIGHT + MARGIN))
126
127        print(f"Click coordinates: ({x}, {y}). Grid coordinates: ({row}, {column})")
128
129        # Make sure we are on-grid. It is possible to click in the upper right
130        # corner in the margin and go to a grid location that doesn't exist
131        if row >= ROW_COUNT or column >= COLUMN_COUNT:
132            # Simply return from this method since nothing needs updating
133            return
134
135        # Flip the location between 1 and 0.
136        if self.grid[row][column] == 0:
137            self.grid[row][column] = 1
138        else:
139            self.grid[row][column] = 0
140
141        # Update the sprite colors to match the new grid
142        self.resync_grid_with_sprites()
143
144
145def main():
146    MyGame(SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_TITLE)
147    arcade.run()
148
149
150if __name__ == "__main__":
151    main()