Modify a text file: $/paddles.java

$/paddles.java

//// Exercise '14 Mar 3

float ballX,ballY, ballDX,ballDY;
float pX, pY, pDX=1, pDY=1;
float qX, qY, qDX=1, qDY=1;

float top=30,bottom=450,left=30,right=610;

void setup() {
  size( 640, 480 );
  reset();
}
void reset() {
  //// Initialize & set random paddle heights.
  pX=right;  qX=left;
  pY=  random(top,bottom);
  qY=  random(top,bottom);
  pDY=  random(2) - random(2);
  qDY=  random(2) - random(2);
  // Ball always starts at left middle.
  ballX=left;  ballY=height/2;
  ballDX=  1 + random(3);  
  ballDY= random(3) -random(3);
}

void draw() {
  //// Next frame:
  scene();
  action();
}

void scene() {
  //// Center line
  background(255);
  fill(0);
  strokeWeight(4);
  line( width/2, 10, width/2, height-10 );
}

void action() {
  //// Ball & paddle.
  ball();
  paddle();
}

void paddle() {
  //// Move & draw two paddles;
  if (pY<top || pY>bottom) pDY = -pDY;
  pY += pDY;
  if (qY<top || qY>bottom) qDY = -qDY;
  qY += qDY;
  rectMode(CENTER);
  fill(255,0,0);
  rect( pX,pY, 20,100 );
  fill(0,0,255);
  rect( qX,qY, 20,100 );
}

void ball() {
  // Move & draw ball; check for bounce.
  if (ballX>right) {
    if (ballY>pY-50 && ballY<pY+50) {
      ballDX=  -ballDX -2+random(4);
      ballDY=  -ballDY -2+random(4);
    }
  }
  if (ballX<left) {
    if (ballY>qY-50 && ballY<qY+50) {
      ballDX=  -ballDX -2+random(4);
      ballDY=  -ballDY -2+random(4);
    }
  }
  if (ballX>right) {
    text( "OUT OF BOUNDS", width/4, height/2 );
  }
  ballX += ballDX;
  ballY += ballDY;
  fill(255,255,0);
  ellipse( ballX,ballY, 20,20);
}

//// EVENT HANDLERS ////
void keyPressed() {
  //// Handle keys
  if (key == 'p') pDY = -pDY;
  if (key == 'l') pDY = pDY * 2;
  if (key == 'q') qDY = -qDY;
  if (key == 'a') qDY = qDY * 2;
  if (key == ' ') reset();
}