Camera Use in a Platformer

camera_platform.py
1"""
2Camera Example
3
4Artwork from: https://kenney.nl
5Tiled available from: https://www.mapeditor.org/
6
7If Python and Arcade are installed, this example can be run from the command line with:
8python -m arcade.examples.camera_platform
9"""
10
11import time
12
13import arcade
14
15TILE_SCALING = 0.5
16PLAYER_SCALING = 0.5
17
18WINDOW_WIDTH = 1280
19WINDOW_HEIGHT = 720
20
21WINDOW_TITLE = "Camera Example"
22SPRITE_PIXEL_SIZE = 128
23GRID_PIXEL_SIZE = SPRITE_PIXEL_SIZE * TILE_SCALING
24
25# How many pixels to keep as a minimum margin between the character
26# and the edge of the screen.
27VIEWPORT_MARGIN_TOP = 60
28VIEWPORT_MARGIN_BOTTOM = 60
29VIEWPORT_RIGHT_MARGIN = 270
30VIEWPORT_LEFT_MARGIN = 270
31
32# Physics
33MOVEMENT_SPEED = 5
34JUMP_SPEED = 23
35GRAVITY = 1.1
36
37# Map Layers
38LAYER_NAME_PLATFORMS = "Platforms"
39LAYER_NAME_COINS = "Coins"
40LAYER_NAME_BOMBS = "Bombs"
41
42
43class GameView(arcade.View):
44 """Main application class."""
45
46 def __init__(self):
47 """
48 Initializer
49 """
50 super().__init__()
51
52 # Our TileMap Object
53 self.tile_map = None
54
55 # Our Scene Object
56 self.scene = None
57
58 # Set up the player
59 self.score = 0
60 self.player_sprite = None
61
62 self.physics_engine = None
63 self.top_of_map = 0
64 self.end_of_map = 0
65 self.game_over = False
66 self.last_time = None
67 self.frame_count = 0
68 self.fps_message = None
69
70 # Cameras
71 self.camera: arcade.camera.Camera2D = None
72 self.gui_camera = None
73
74 self.camera_shake = None
75
76 self.shake_offset_1 = 0
77 self.shake_offset_2 = 0
78 self.shake_vel_1 = 0
79 self.shake_vel_2 = 0
80
81 # Text
82 self.text_fps = arcade.Text(
83 "",
84 x=10,
85 y=40,
86 color=arcade.color.BLACK,
87 font_size=14,
88 )
89 self.text_score = arcade.Text(
90 f"Score: {self.score}",
91 x=10,
92 y=20,
93 color=arcade.color.BLACK,
94 font_size=14,
95 )
96
97 def setup(self):
98 """Set up the game and initialize the variables."""
99
100 # Map name
101 map_name = ":resources:tiled_maps/level_1.json"
102
103 # Layer Specific Options for the Tilemap
104 layer_options = {
105 LAYER_NAME_PLATFORMS: {
106 "use_spatial_hash": True,
107 },
108 LAYER_NAME_COINS: {
109 "use_spatial_hash": True,
110 },
111 LAYER_NAME_BOMBS: {
112 "use_spatial_hash": True,
113 },
114 }
115
116 # Load in TileMap
117 self.tile_map = arcade.load_tilemap(map_name, TILE_SCALING, layer_options)
118
119 # Initiate New Scene with our TileMap, this will automatically add all layers
120 # from the map as SpriteLists in the scene in the proper order.
121 self.scene = arcade.Scene.from_tilemap(self.tile_map)
122
123 # Set up the player
124 self.player_sprite = arcade.Sprite(
125 ":resources:images/animated_characters/female_person/femalePerson_idle.png",
126 scale=PLAYER_SCALING,
127 )
128
129 # Starting position of the player
130 self.player_sprite.center_x = 196
131 self.player_sprite.center_y = 128
132 self.scene.add_sprite("Player", self.player_sprite)
133
134 self.camera = arcade.camera.Camera2D()
135
136 self.camera_shake = arcade.camera.grips.ScreenShake2D(self.camera.view_data,
137 max_amplitude=12.5,
138 acceleration_duration=0.05,
139 falloff_time=0.20,
140 shake_frequency=15.0)
141
142 # Center camera on user
143 self.pan_camera_to_user()
144
145 # Calculate the right edge of the my_map in pixels
146 self.top_of_map = self.tile_map.height * GRID_PIXEL_SIZE
147 self.end_of_map = self.tile_map.width * GRID_PIXEL_SIZE
148
149 # --- Other stuff
150 # Set the background color
151 if self.tile_map.background_color:
152 self.background_color = self.tile_map.background_color
153
154 # Keep player from running through the wall_list layer
155 self.physics_engine = arcade.PhysicsEnginePlatformer(
156 self.player_sprite,
157 self.scene.get_sprite_list(LAYER_NAME_PLATFORMS),
158 gravity_constant=GRAVITY,
159 )
160
161 self.game_over = False
162
163 def on_resize(self, width, height):
164 """Resize window"""
165 super().on_resize(width, height)
166 self.camera.match_window()
167
168 def on_draw(self):
169 """Render the screen."""
170 self.clear()
171
172 self.camera_shake.update_camera()
173 with self.camera.activate():
174 # Draw our Scene
175 self.scene.draw()
176 # Readjust the camera so the screen shake doesn't affect
177 # the camera following algorithm.
178 self.camera_shake.readjust_camera()
179
180 with self.window.default_camera.activate():
181 # Update fps text periodically
182 if self.last_time and self.frame_count % 60 == 0:
183 fps = 1.0 / (time.time() - self.last_time) * 60
184 self.text_fps.text = f"FPS: {fps:5.2f}"
185
186 self.text_fps.draw()
187
188 if self.frame_count % 60 == 0:
189 self.last_time = time.time()
190
191 # Draw Score
192 self.text_score.draw()
193
194 # Draw game over
195 if self.game_over:
196 arcade.draw_text("Game Over", self.width/2, self.height/2, arcade.color.BLACK,
197 30)
198
199 self.frame_count += 1
200
201 def on_key_press(self, key, modifiers):
202 """
203 Called whenever a key is pressed
204 """
205 if key == arcade.key.UP:
206 if self.physics_engine.can_jump():
207 self.player_sprite.change_y = JUMP_SPEED
208 elif key == arcade.key.LEFT:
209 self.player_sprite.change_x = -MOVEMENT_SPEED
210 elif key == arcade.key.RIGHT:
211 self.player_sprite.change_x = MOVEMENT_SPEED
212
213 def on_key_release(self, key, modifiers):
214 """
215 Called when the user presses a mouse button.
216 """
217 if key == arcade.key.LEFT or key == arcade.key.RIGHT:
218 self.player_sprite.change_x = 0
219
220 def pan_camera_to_user(self, panning_fraction: float = 1.0):
221 """
222 Manage Scrolling
223
224 Args:
225 panning_fraction:
226 Number from 0 to 1. Higher the number, faster we
227 pan the camera to the user.
228 """
229
230 # This spot would center on the user
231 screen_center_x, screen_center_y = self.player_sprite.position
232 if screen_center_x < self.camera.viewport_width/2:
233 screen_center_x = self.camera.viewport_width/2
234 if screen_center_y < self.camera.viewport_height/2:
235 screen_center_y = self.camera.viewport_height/2
236 user_centered = screen_center_x, screen_center_y
237
238 self.camera.position = arcade.math.lerp_2d(
239 self.camera.position,
240 user_centered,
241 panning_fraction,
242 )
243
244 def on_update(self, delta_time):
245 """Movement and game logic"""
246
247 if self.player_sprite.right >= self.end_of_map:
248 self.game_over = True
249
250 # Call update on all sprites
251 if not self.game_over:
252 self.physics_engine.update()
253 self.camera_shake.update(delta_time)
254
255 coins_hit = arcade.check_for_collision_with_list(
256 self.player_sprite, self.scene.get_sprite_list("Coins")
257 )
258 for coin in coins_hit:
259 coin.remove_from_sprite_lists()
260 self.score += 1
261
262 # Bomb hits
263 bombs_hit = arcade.check_for_collision_with_list(
264 self.player_sprite, self.scene.get_sprite_list("Bombs")
265 )
266 for bomb in bombs_hit:
267 bomb.remove_from_sprite_lists()
268 self.camera_shake.start()
269
270 # Pan to the user
271 self.pan_camera_to_user(panning_fraction=0.12)
272
273 # Update score text
274 self.text_score.text = f"Score: {self.score}"
275
276
277def main():
278 """ Main function """
279 # Create a window class. This is what actually shows up on screen
280 window = arcade.Window(WINDOW_WIDTH, WINDOW_HEIGHT, WINDOW_TITLE)
281
282 # Create and setup the GameView
283 game = GameView()
284 game.setup()
285
286 # Show GameView on screen
287 window.show_view(game)
288
289 # Start the arcade game loop
290 arcade.run()
291
292
293if __name__ == "__main__":
294 main()