# Gulp Catch, part 3: through the mouth # # Flip walks along the top and drops a pancake from his pan every so often. # The Left and Right arrows drive Gulp. A pancake that touches his mouth is caught # and disappears; a missed one lands on the counter. # Nobody keeps score yet: that comes in part 4. # # If the arrows do nothing, click the game window first. # To run: open this file in IDLE and press F5. # Closing the window stops the loop with a red message. # Part 4 shows how a game closes its window properly. # # Everything after a # is a note for people. Python skips it. from tkinter import Tk, Canvas import time width = 480 height = 640 counter_top = 600 # pancakes land here fastest_fall = 12 # top falling speed. Much faster, and a pancake can jump past the mouth toss_every = 90 # steps between two pancakes: one is down before the next def touching(a, b): # a and b are boxes: [left, top, right, bottom]. They touch when they overlap across and down. return a[0] < b[2] and b[0] < a[2] and a[1] < b[3] and b[1] < a[3] class Flip: def __init__(self, canvas): self.canvas = canvas self.x = 120 self.speed = 2 x = self.x self.parts = [ canvas.create_line(x, 58, x, 40, width=3, fill="gray30"), canvas.create_oval(x - 6, 32, x + 6, 44, fill="orange red", outline=""), canvas.create_rectangle(x - 22, 58, x + 22, 90, fill="light sea green", outline="dark slate gray", width=2), canvas.create_oval(x - 13, 68, x - 5, 76, fill="black"), canvas.create_oval(x + 5, 68, x + 13, 76, fill="black"), canvas.create_rectangle(x - 28, 92, x + 28, 140, fill="light sea green", outline="dark slate gray", width=2), canvas.create_line(x + 28, 108, x + 50, 108, width=4, fill="gray30"), canvas.create_oval(x + 46, 100, x + 86, 114, fill="gray20", outline=""), ] def step(self): # Flip walks along the top and turns around at the walls. self.x = self.x + self.speed for part in self.parts: self.canvas.move(part, self.speed, 0) if self.x <= 40 or self.x >= width - 90: self.speed = -self.speed class Pancake: def __init__(self, canvas, x, y): self.canvas = canvas self.x = x self.y = y self.speed_y = 7 self.landed = False self.shape = canvas.create_oval(x - 20, y - 7, x + 20, y + 7, fill="goldenrod", outline="dark goldenrod", width=2) def step(self): # Never fall further in one step than the mouth is tall (40), # or a pancake can jump right past it. if self.speed_y > fastest_fall: self.speed_y = fastest_fall # Land on the counter. if self.y + self.speed_y > counter_top - 7: self.speed_y = counter_top - 7 - self.y self.landed = True self.y = self.y + self.speed_y self.canvas.move(self.shape, 0, self.speed_y) def box(self): # The pancake's box: [left, top, right, bottom] return [self.x - 20, self.y - 7, self.x + 20, self.y + 7] def hide(self): # A caught pancake is not deleted: it is hidden. self.canvas.itemconfig(self.shape, state="hidden") gulp_speed = 7 # how far Gulp moves in one step class Gulp: def __init__(self, canvas): self.canvas = canvas self.x = width / 2 self.speed = 0 x = self.x c = canvas self.parts = [ c.create_oval(x - 100, 470, x + 100, 730, fill="plum4", outline=""), c.create_oval(x - 88, 548, x - 70, 566, fill="thistle", outline=""), c.create_oval(x + 66, 534, x + 84, 552, fill="thistle", outline=""), c.create_oval(x - 62, 584, x - 46, 600, fill="thistle", outline=""), c.create_oval(x + 44, 582, x + 60, 598, fill="thistle", outline=""), c.create_oval(x - 28, 490, x - 14, 504, fill="white", outline=""), c.create_oval(x - 24, 494, x - 18, 500, fill="black"), c.create_oval(x + 14, 490, x + 28, 504, fill="white", outline=""), c.create_oval(x + 18, 494, x + 24, 500, fill="black"), c.create_oval(x - 60, 520, x + 60, 580, fill="gray10", outline=""), ] # A key only sets the speed. The loop does the moving, a little every pass. # The speed lives in the object: a plain name set inside a function would stay inside it. def go_left(self, event): self.speed = -gulp_speed def go_right(self, event): self.speed = gulp_speed def stop_left(self, event): if self.speed < 0: self.speed = 0 def stop_right(self, event): if self.speed > 0: self.speed = 0 def mouth_box(self): return [self.x - 60, 520, self.x + 60, 560] def step(self): # Move only if the new place is inside: Gulp is 200 wide, so his middle stays 100 from each wall. new_x = self.x + self.speed if new_x > 100 and new_x < width - 100: self.x = new_x for part in self.parts: self.canvas.move(part, self.speed, 0) class Game: def __init__(self): self.window = Tk() self.window.title("Gulp Catch") self.canvas = Canvas(self.window, width=width, height=height, bg="powder blue") self.canvas.pack() self.flip = Flip(self.canvas) self.gulp = Gulp(self.canvas) self.pancake = None self.toss_timer = 30 self.canvas.create_rectangle(0, 600, width, height, fill="slate gray", outline="") self.canvas.bind_all("", self.gulp.go_left) self.canvas.bind_all("", self.gulp.go_right) self.canvas.bind_all("", self.gulp.stop_left) self.canvas.bind_all("", self.gulp.stop_right) def step(self): self.flip.step() self.gulp.step() self.toss_timer = self.toss_timer - 1 if self.toss_timer == 0: # Flip drops a new pancake from his pan; the last one is left where it is self.pancake = Pancake(self.canvas, self.flip.x + 66, 107) self.toss_timer = toss_every if self.pancake != None and not self.pancake.landed: self.pancake.step() if touching(self.pancake.box(), self.gulp.mouth_box()): self.pancake.hide() self.pancake = None def run(self): # The game is this loop: move everything a little, show it, wait, again. while True: self.step() self.window.update() time.sleep(0.02) game = Game() game.run()