Added a pong game example

Author: pixelpixi

examples/pong.py

@@ -0,0 +1,182 @@
+
+import modulo
+import time
+import math
+
+lastUpdateTime = time.time()
+
+
+class Pong :
+
+    def __init__(self) :
+        self._port = modulo.Port()
+        self._display = modulo.Display(self._port)
+        self._knob = modulo.Knob(self._port)
+
+        self._width = self._display.get_width()
+        self._height = self._display.get_height()
+        self._paddleWidth = 3
+        self._paddleHeight = 10
+        self._leftPaddleSpeed = 30
+
+        self._leftPaddlePos = self._height/2
+        self._rightPaddlePos = self._height/2
+        self._knobPos = self._knob.get_position()
+
+        self._paused = True
+        self._lastUpdateTime = time.time()
+        self._ballX = 10
+        self._ballY = self._height/2
+
+        self._ballSpeed = 30
+        self._ballDx = .9
+        self._ballDy = .1
+
+        self._rightScore = 0
+        self._leftScore = 0
+
+    def update_input(self) :
+        newKnobPos = self._knob.get_position()
+        self._rightPaddlePos += 5*(newKnobPos - self._knobPos)
+        self._knobPos = newKnobPos
+
+        minPaddlePosition = self._paddleHeight/2
+        maxPaddlePosition = self._height-self._paddleHeight/2
+
+        self._rightPaddlePos = max(self._rightPaddlePos, minPaddlePosition)
+        self._rightPaddlePos = min(self._rightPaddlePos, maxPaddlePosition)
+
+    def end_round(self) :
+        self.draw()
+
+        # Wait for 3 seconds
+        pauseStartTime = time.time()
+        while time.time() < pauseStartTime+3 :
+            self._knob.set_hsv(time.time()-pauseStartTime, 1, 1)
+        self._knob.set_color(0,0,0)
+
+        # Move the ball back to the center
+        self._ballX = self._display.get_width()/2
+        self._ballY = self._display.get_height()/2
+
+        # Reset the last update time, since we want to start the game from now
+        self._lastUpdateTime = time.time()
+
+    def check_right_goal(self) :
+        rightGoal = self._display.get_width()-self._paddleWidth
+
+        if (self._ballX < rightGoal) :
+            return False
+
+        posOnPaddle = self._ballY-self._rightPaddlePos
+
+        # Check and see if the ball missed the paddle
+        if abs(posOnPaddle) > .6*self._paddleHeight :
+            return True
+
+        angle = .5*math.pi*posOnPaddle/self._paddleHeight
+        self._ballDx = -math.cos(angle)
+        self._ballDy = math.sin(angle)
+        return False
+
+    def check_left_goal(self) :
+        leftGoal = self._paddleWidth
+
+        if (self._ballX > leftGoal) :
+            return False
+
+        posOnPaddle = self._ballY-self._leftPaddlePos
+
+        # Check and see if the ball missed the paddle
+        if abs(posOnPaddle) > .6*self._paddleHeight :
+            return True
+
+        angle = .5*math.pi*posOnPaddle/self._paddleHeight
+        self._ballDx = -math.cos(angle)
+        self._ballDy = math.sin(angle)
+        return False
+
+
+    def update_game(self) :
+        if self._paused :
+            return False
+
+        leftGoal = self._paddleWidth
+
+        if self.check_right_goal() :
+            self._leftScore += 1
+            self.end_round()
+            return
+
+        if self.check_left_goal() :
+            self._rightScore += 1
+            self.end_round()
+            return
+
+        currentTime = time.time()
+        dt = currentTime-self._lastUpdateTime
+        self._lastUpdateTime = time.time()
+
+        if (self._leftPaddlePos > self._ballY+5) :
+            self._leftPaddlePos -= dt*self._leftPaddleSpeed
+        if (self._leftPaddlePos < self._ballY-5) :
+            self._leftPaddlePos += dt*self._leftPaddleSpeed
+
+        if (self._ballX <= leftGoal) :
+            self._ballDx = -self._ballDx
+
+        if (self._ballY >= self._height-1 or
+            self._ballY <= 0) :
+            self._ballDy = -self._ballDy
+
+        self._ballX += self._ballSpeed*self._ballDx*dt
+        self._ballY += self._ballSpeed*self._ballDy*dt
+
+    def draw(self) :
+        self._display.clear()
+
+        self._display.draw_ellipse(self._ballX, self._ballY, 2, 2, 1)
+
+        self._display.draw_rectangle(self._width-self._paddleWidth,
+            self._rightPaddlePos-self._paddleHeight/2, self._paddleWidth,
+            self._paddleHeight,
+            fill=1);
+
+        self._display.draw_rectangle(0,
+            self._leftPaddlePos-self._paddleHeight/2, self._paddleWidth,
+            self._paddleHeight,
+            fill=1);
+
+        self._display.set_cursor(self._width/3, 0)
+        self._display.write(self._leftScore)
+
+        self._display.set_cursor(self._width*2/3, 0)
+        self._display.write(self._rightScore)
+
+        if self._paused :
+            self._display.draw_rectangle(25, 10,
+                self._width-40, self._height-20, fill=0, outline=1)
+            self._display.set_cursor(0, 15)
+            self._display.writeln("        Paused.")
+            self._display.writeln("      Press Knob")
+            self._display.writeln("      to continue")
+
+
+        self._display.update()
+
+    def run(self) :
+        knobWasPressed = False
+        while True :
+            knobIsPressed = self._knob.get_button()
+            if knobIsPressed and not knobWasPressed :
+                self._paused = not self._paused
+                self._lastUpdateTime = time.time()
+            knobWasPressed = knobIsPressed
+
+            self.update_input()
+            self.update_game()
+            self.draw()
+
+pong = Pong()
+pong.run()
+