""" Use Pymunk physics engine. For more info on Pymunk see: http://www.pymunk.org/en/latest/ To install pymunk: pip install pymunk Artwork from http://kenney.nl If Python and Arcade are installed, this example can be run from the command line with: python -m arcade.examples.pymunk_box_stacks Click and drag with the mouse to move the boxes. """ import arcade import pymunk import timeit import math import os SCREEN_WIDTH = 1800 SCREEN_HEIGHT = 800 SCREEN_TITLE = "Pymunk test" class PhysicsSprite(arcade.Sprite): def __init__(self, pymunk_shape, filename): super().__init__(filename, center_x=pymunk_shape.body.position.x, center_y=pymunk_shape.body.position.y) self.pymunk_shape = pymunk_shape class CircleSprite(PhysicsSprite): def __init__(self, pymunk_shape, filename): super().__init__(pymunk_shape, filename) self.width = pymunk_shape.radius * 2 self.height = pymunk_shape.radius * 2 class BoxSprite(PhysicsSprite): def __init__(self, pymunk_shape, filename, width, height): super().__init__(pymunk_shape, filename) self.width = width self.height = height class MyGame(arcade.Window): """ Main application class. """ def __init__(self, width, height, title): super().__init__(width, height, title) # Set the working directory (where we expect to find files) to the same # directory this .py file is in. You can leave this out of your own # code, but it is needed to easily run the examples using "python -m" # as mentioned at the top of this program. file_path = os.path.dirname(os.path.abspath(__file__)) os.chdir(file_path) arcade.set_background_color(arcade.color.DARK_SLATE_GRAY) # -- Pymunk self.space = pymunk.Space() self.space.iterations = 35 self.space.gravity = (0.0, -900.0) # Lists of sprites or lines self.sprite_list = arcade.SpriteList() self.static_lines = [] # Used for dragging shapes around with the mouse self.shape_being_dragged = None self.last_mouse_position = 0, 0 self.draw_time = 0 self.processing_time = 0 # Create the floor floor_height = 80 body = pymunk.Body(body_type=pymunk.Body.STATIC) shape = pymunk.Segment(body, [0, floor_height], [SCREEN_WIDTH, floor_height], 0.0) shape.friction = 10 self.space.add(shape) self.static_lines.append(shape) # Create the stacks of boxes for row in range(10): for column in range(10): size = 32 mass = 1.0 x = 500 + column * 32 y = (floor_height + size / 2) + row * size moment = pymunk.moment_for_box(mass, (size, size)) body = pymunk.Body(mass, moment) body.position = pymunk.Vec2d(x, y) shape = pymunk.Poly.create_box(body, (size, size)) shape.elasticity = 0.2 shape.friction = 0.9 self.space.add(body, shape) # body.sleep() sprite = BoxSprite(shape, "images/boxCrate_double.png", width=size, height=size) self.sprite_list.append(sprite) def on_draw(self): """ Render the screen. """ # This command has to happen before we start drawing arcade.start_render() # Start timing how long this takes draw_start_time = timeit.default_timer() # Draw all the sprites self.sprite_list.draw() # Draw the lines that aren't sprites for line in self.static_lines: body = line.body pv1 = body.position + line.a.rotated(body.angle) pv2 = body.position + line.b.rotated(body.angle) arcade.draw_line(pv1.x, pv1.y, pv2.x, pv2.y, arcade.color.WHITE, 2) # Display timings output = f"Processing time: {self.processing_time:.3f}" arcade.draw_text(output, 20, SCREEN_HEIGHT - 20, arcade.color.WHITE, 12) output = f"Drawing time: {self.draw_time:.3f}" arcade.draw_text(output, 20, SCREEN_HEIGHT - 40, arcade.color.WHITE, 12) self.draw_time = timeit.default_timer() - draw_start_time def on_mouse_press(self, x, y, button, modifiers): if button == arcade.MOUSE_BUTTON_LEFT: self.last_mouse_position = x, y # See if we clicked on anything shape_list = self.space.point_query((x, y), 1, pymunk.ShapeFilter()) # If we did, remember what we clicked on if len(shape_list) > 0: self.shape_being_dragged = shape_list[0] elif button == arcade.MOUSE_BUTTON_RIGHT: # With right mouse button, shoot a heavy coin fast. mass = 60 radius = 10 inertia = pymunk.moment_for_circle(mass, 0, radius, (0, 0)) body = pymunk.Body(mass, inertia) body.position = x, y body.velocity = 2000, 0 shape = pymunk.Circle(body, radius, pymunk.Vec2d(0, 0)) shape.friction = 0.3 self.space.add(body, shape) sprite = CircleSprite(shape, "images/coin_01.png") self.sprite_list.append(sprite) def on_mouse_release(self, x, y, button, modifiers): if button == arcade.MOUSE_BUTTON_LEFT: # Release the item we are holding (if any) self.shape_being_dragged = None def on_mouse_motion(self, x, y, dx, dy): if self.shape_being_dragged is not None: # If we are holding an object, move it with the mouse self.last_mouse_position = x, y self.shape_being_dragged.shape.body.position = self.last_mouse_position self.shape_being_dragged.shape.body.velocity = dx * 20, dy * 20 def update(self, delta_time): start_time = timeit.default_timer() # Check for balls that fall off the screen for sprite in self.sprite_list: if sprite.pymunk_shape.body.position.y < 0: # Remove balls from physics space self.space.remove(sprite.pymunk_shape, sprite.pymunk_shape.body) # Remove balls from physics list sprite.kill() # Update physics # Use a constant time step, don't use delta_time # See "Game loop / moving time forward" # http://www.pymunk.org/en/latest/overview.html#game-loop-moving-time-forward self.space.step(1 / 60.0) # If we are dragging an object, make sure it stays with the mouse. Otherwise # gravity will drag it down. if self.shape_being_dragged is not None: self.shape_being_dragged.shape.body.position = self.last_mouse_position self.shape_being_dragged.shape.body.velocity = 0, 0 # Move sprites to where physics objects are for sprite in self.sprite_list: sprite.center_x = sprite.pymunk_shape.body.position.x sprite.center_y = sprite.pymunk_shape.body.position.y sprite.angle = math.degrees(sprite.pymunk_shape.body.angle) # Save the time it took to do this. self.processing_time = timeit.default_timer() - start_time def main(): MyGame(SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_TITLE) arcade.run() if __name__ == "__main__": main()