# Aim and Shoot Bullets¶

sprite_bullets_aimed.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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 """ Sprite Bullets Simple program to show basic sprite usage. Artwork from http://kenney.nl """ import random import arcade import math SPRITE_SCALING = 0.5 SCREEN_WIDTH = 800 SCREEN_HEIGHT = 600 BULLET_SPEED = 5 window = None class Bullet(arcade.Sprite): def update(self): self.center_x += self.change_x self.center_y += self.change_y class MyApplication(arcade.Window): """ Main application class. """ def __init__(self, screen_width, screen_height): super().__init__(SCREEN_WIDTH, SCREEN_HEIGHT, "Sprites and Bullets Demo") """ Set up the game and initialize the variables. """ # Sprite lists self.all_sprites_list = arcade.SpriteList() self.coin_list = arcade.SpriteList() self.bullet_list = arcade.SpriteList() # Set up the player self.score = 0 self.player_sprite = arcade.Sprite("images/character.png", SPRITE_SCALING) self.player_sprite.center_x = 50 self.player_sprite.center_y = 70 self.all_sprites_list.append(self.player_sprite) for i in range(50): # Create the coin instance coin = arcade.Sprite("images/coin_01.png", SPRITE_SCALING / 3) # Position the coin coin.center_x = random.randrange(screen_width) coin.center_y = random.randrange(120, screen_height) # Add the coin to the lists self.all_sprites_list.append(coin) self.coin_list.append(coin) # Set the background color arcade.set_background_color(arcade.color.AMAZON) def on_draw(self): """ Render the screen. """ # This command has to happen before we start drawing arcade.start_render() # Draw all the sprites. self.all_sprites_list.draw() # Put the text on the screen. output = "Score: {}".format(self.score) arcade.draw_text(output, 10, 20, arcade.color.WHITE, 14) def on_mouse_press(self, x, y, button, modifiers): """ Called whenever the mouse moves. """ # Create a bullet bullet = Bullet("images/laserBlue01.png", SPRITE_SCALING * 1.5) # Position the bullet at the player's current location start_x = self.player_sprite.center_x start_y = self.player_sprite.center_y bullet.center_x = start_x bullet.center_y = start_y # Get from the mouse the destination location for the bullet dest_x = x dest_y = y # Do math to calculate how to get the bullet to the destination. # Calculation the angle in radians between the start points # and end points. This is the angle the bullet will travel. x_diff = dest_x - start_x y_diff = dest_y - start_y angle = math.atan2(y_diff, x_diff) print("Bullet angle: {:.2f}".format(bullet.angle)) # Angle the bullet sprite so it doesn't look like it is flying # sideways. bullet.angle = math.degrees(angle) # Taking into account the angle, calculate our change_x # and change_y. Velocity is how fast the bullet travels. bullet.change_x = math.cos(angle) * BULLET_SPEED bullet.change_y = math.sin(angle) * BULLET_SPEED # Add the bullet to the appropriate lists self.all_sprites_list.append(bullet) self.bullet_list.append(bullet) def update(self, delta_time): """ Movement and game logic """ # Call update on all sprites (The sprites don't do much in this # example though.) self.all_sprites_list.update() # Loop through each bullet for bullet in self.bullet_list: # Check this bullet to see if it hit a coin hit_list = arcade.check_for_collision_with_list(bullet, self.coin_list) # If it did, get rid of the bullet if len(hit_list) > 0: bullet.kill() # For every coin we hit, add to the score and remove the coin for coin in hit_list: coin.kill() self.score += 1 # If the bullet flies off-screen, remove it. if bullet.bottom > SCREEN_HEIGHT: bullet.kill() def main(): MyApplication(SCREEN_WIDTH, SCREEN_HEIGHT) arcade.run() if __name__ == "__main__": main()