pythonista_pong_example.py

import scene
import copy
import math
import ui

class Paddle(scene.ShapeNode):
    def __init__(self, x, y, parent=None):
        path = ui.Path.rect(0,0, 40, 200)
        super(Paddle, self).__init__(path, position=(x, y), fill_color='green', parent=parent)
        self.touch = None

    def touch_began(self, touch):
        if touch.location in (self.frame):
            if not self.touch:
                self.touch = copy.copy(touch)

    def touch_moved(self, touch):
        if self.touch and touch.touch_id == self.touch.touch_id:
            dx = touch.location.y - self.touch.location.y
            if abs(dx*1.0) > 5:
                self.touch.location.y = touch.location.y
                self.position = (self.position[0], touch.location.y)

    def touch_ended(self, touch):
        if self.touch and touch.touch_id == self.touch.touch_id:
            self.touch = None


class Ball(scene.ShapeNode):
    def __init__(self, x, y, parent=None):
        path = ui.Path.oval(0,0, 10, 10)
        super(Ball, self).__init__(path, position=(x, y), fill_color='red', parent=parent)
        self.dx, self.dy = 5, 0

    def update(self):
        self.position = (self.position[0] + self.dx,
                            self.position[1]+self.dy)
        if (self.position[1] > self.parent.bounds.h) or (self.position[1] < 0) :
            self.dy = -self.dy
            return
        if (self.frame.x > self.parent.bounds.w):
            self.dx, self.dy = 5, 0
            self.position = (400, 300)
            self.parent.score_left.increment()
            return
        if (self.frame.x < 0):
            self.dx, self.dy =  -5, 0
            self.position = (400, 300)
            self.parent.score_right.increment()
            return
        if self.frame.intersects(self.parent.paddle_left.frame):
            self.dx = -self.dx
            h = self.parent.paddle_left.frame.h/2
            self.dy += (self.frame.y+self.frame.h/2 - (self.parent.paddle_left.frame.y+h))*1.0/h*5
        if self.frame.intersects(self.parent.paddle_right.frame):
            self.dx = -self.dx
            h = self.parent.paddle_right.frame.h/2
            self.dy += (self.frame.y+self.frame.h/2 - (self.parent.paddle_right.frame.y+h))*1.0/h*5


class Score(object):
    def __init__(self, x, y, parent=None):
        self.value = 0
        self.label = scene.LabelNode(
                        "{}".format(self.value),
                        position=(x, y),                        
                        font=('Helvetica', 40),
                        parent=parent)

    def increment(self):
        self.value += 1
        self.label.text = "{}".format(self.value)
        
    def reset(self):
        self.value = 0
        self.label.text = "{}".format(self.value)
                 
class Pong(scene.Scene):
    def setup(self):
        self.paddle_left = Paddle(50, self.size[1]/2.0, parent=self)
        self.paddle_right = Paddle(self.size[0]-50, self.size[1]/2.0, parent=self)
        self.ball = Ball(self.size[0]/2.0, self.size[1]/2.0, parent=self)
        self.score_left = Score(self.size[0]*.25, 25, parent=self)
        self.score_right = Score(self.size[0]*.75, 25, parent=self)
        
    def update(self):
        self.ball.update()

    def touch_began(self, touch):
        self.paddle_left.touch_began(touch)
        self.paddle_right.touch_began(touch)

    def touch_moved(self, touch):
        self.paddle_left.touch_moved(touch)
        self.paddle_right.touch_moved(touch)

    def touch_ended(self, touch):
        self.paddle_left.touch_ended(touch)
        self.paddle_right.touch_ended(touch)
    
scene.run(Pong(), show_fps=True)