""" Example using Pymunk physics engine @author: Paul Vincent Craven @author: Robert Duvall (added classes, simplified code) Artwork from https://kenney.nl """ import arcade import pymunk import random import math # Choose game window size and a name for your game to appear in the title bar SCREEN_WIDTH = 800 SCREEN_HEIGHT = 800 GAME_NAME = 'Pymunk Pegboard Example' # Choose number and placement of bumpers in the game BUMPER_ROWS = 5 BUMPER_COLUMNS = 5 BUMPER_SIZE = 20 BUMPER_SPACING = 150 BUMPER_IMAGE = ':resources:images/pinball/bumper.png' # Choose placement and look of floor at the bottom of the game FLOOR_OFFSET_Y = 10 FLOOR_INCLINE_X = 50 FLOOR_INCLINE_Y = 30 FLOOR_WIDTH = 2 # Choose ball size, image, and physics mass BALL_SIZE = 15 BALL_MASS = 0.5 BALL_IMAGE = ':resources:images/items/gold_1.png' # Choose physics parameters based on (very scientific) pixels per time step PHYSICS_TIME_STEP = 1 / 60.0 GRAVITY = -900 FRICTION = 0.5 class PymunkSprite(arcade.Sprite): """ This class represents a Sprite that works with the Pymunk physics system by keeping the Sprite's values in sync with the physics Shape's values. """ def __init__(self, filename, pymunk_shape, x, y): super().__init__(filename) # set Pymunk specific attributes so it works properly self.pymunk_shape = pymunk_shape self.pymunk_shape.body.position = [x, y] self.pymunk_shape.friction = FRICTION # set Arcade Sprite specific attributes to correspond to physics values self.width = pymunk_shape.radius * 2 self.height = pymunk_shape.radius * 2 self.center_x = x self.center_y = y def update(self): """ Update Sprite's position and angle based on those calculated by Pymunk rather than our own (dx, dy) """ self.center_x = self.pymunk_shape.body.position.x self.center_y = self.pymunk_shape.body.position.y self.angle = math.degrees(self.pymunk_shape.body.angle) class StaticFloor: """ This class represents a shape that cannot be moved and is drawn as a simple line (not a default Sprite). """ def __init__(self, start, end, color): # create an unmoving physics object self.body = pymunk.Body(body_type=pymunk.Body.STATIC) self.shape = pymunk.Segment(self.body, start, end, 0.0) self.shape.friction = FRICTION # set color to be used when drawing self.color = color def draw(self): """ Draw as a colored Line that represents the physics shape. """ pv1 = self.body.position + self.shape.a.rotated(self.body.angle) pv2 = self.body.position + self.shape.b.rotated(self.body.angle) arcade.draw_line(pv1.x, pv1.y, pv2.x, pv2.y, self.color, FLOOR_WIDTH) class Game(arcade.Window): """ This class represents the entire "game" (there is no interaction, just resetting): - setting up any objects to appear in game (in the constructor) - updating their values (in method on_update) - drawing them (in method on_draw) - responding to key input (in method on_key_press) """ def __init__(self, width, height, title): super().__init__(width, height, title) self.peg_list = arcade.SpriteList() self.ball_list = arcade.SpriteList() self.floor_list = [] # setup Pymunk self.space = pymunk.Space() self.space.gravity = (0.0, GRAVITY) def setup(self): """ """ self.space = pymunk.Space() self.space.gravity = (0.0, GRAVITY) self.peg_list.clear() self.ball_list.clear() self.floor_list = [ StaticFloor([0, FLOOR_OFFSET_Y], [SCREEN_WIDTH, FLOOR_OFFSET_Y], arcade.color.WHITE), StaticFloor([SCREEN_WIDTH - FLOOR_INCLINE_X, FLOOR_OFFSET_Y], [SCREEN_WIDTH, FLOOR_INCLINE_Y], arcade.color.WHITE), StaticFloor([FLOOR_INCLINE_X, FLOOR_OFFSET_Y], [0, FLOOR_INCLINE_Y], arcade.color.WHITE) ] for f in self.floor_list: self.space.add(f.shape, f.body) for row in range(BUMPER_ROWS): for col in range(BUMPER_COLUMNS): self.make_bumper(BUMPER_SIZE, col * BUMPER_SPACING + (BUMPER_SPACING // 2 * (row % 2 + 1)), row * BUMPER_SPACING + BUMPER_SPACING // 2) arcade.schedule(self.make_ball_schedule, 0.4) arcade.set_background_color(arcade.color.DARK_SLATE_GRAY) def make_ball(self, mass, radius, x, y): """ """ inertia = pymunk.moment_for_circle(mass, 0, radius, [0, 0]) body = pymunk.Body(mass, inertia) shape = pymunk.Circle(body, radius) self.ball_list.append(PymunkSprite(BALL_IMAGE, shape, x, y)) self.space.add(body, shape) def make_bumper(self, radius, x, y): """ """ body = pymunk.Body(body_type=pymunk.Body.STATIC) shape = pymunk.Circle(body, radius) self.peg_list.append(PymunkSprite(BUMPER_IMAGE, shape, x, y)) self.space.add(body, shape) def make_ball_schedule(self, dt): """ """ self.make_ball(BALL_MASS, BALL_SIZE, random.randint(0, SCREEN_WIDTH), SCREEN_HEIGHT) def on_key_press(self, key, modifiers): """ Called whenever a key is pressed. """ if key == arcade.key.R: arcade.unschedule(self.make_ball_schedule) self.setup() def on_draw(self): """ Draw all the game objects on the screen. """ # DO NOT CHANGE -- always clear the screen as the FIRST step self.clear() # now draw the game objects self.peg_list.draw() self.ball_list.draw() for f in self.floor_list: f.draw() def on_update(self, dt): """ """ # update physics, using a constant time step instead of varying dt self.space.step(PHYSICS_TIME_STEP) # update moving physics objects for ball in self.ball_list: ball.update() # check if ball has fallen off the screen if ball.center_y < 0: # remove balls from drawing list AND physics space ball.remove_from_sprite_lists() self.space.remove(ball.pymunk_shape, ball.pymunk_shape.body) # Create the game and set initial scene game = Game(SCREEN_WIDTH, SCREEN_HEIGHT, GAME_NAME) game.setup() # Play the game forever arcade.run()