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                <script type="application/processing">
float centerRectX = 125;
float centerRectY = 100;
float centerRectWidth = 50;
float centerRectHeight = 100;

float bouncingRectX = 10;
float bouncingRectY = 10;
float bouncingRectWidth = 100;
float bouncingRectHeight = 50;
float bouncingRectSpeedX = 1;
float bouncingRectSpeedY = 2;

void setup() {
  size(300, 300);

void draw() {

  //draw the center rectangle
  rect(centerRectX, centerRectY, centerRectWidth, centerRectHeight);

  //if I keep moving in my current X direction, will I collide with the center rectangle?
  if (bouncingRectX + bouncingRectWidth + bouncingRectSpeedX > centerRectX && 
      bouncingRectX + bouncingRectSpeedX < centerRectX + centerRectWidth && 
      bouncingRectY + bouncingRectHeight > centerRectY && 
      bouncingRectY < centerRectY + centerRectHeight) {
    bouncingRectSpeedX *= -1;
  //bounce off left and right edges of screen
  else if(bouncingRectX < 0 || bouncingRectX + bouncingRectWidth > width){
    bouncingRectSpeedX *= -1;
  //if I keep moving in my current Y direction, will I collide with the center rectangle?
  if (bouncingRectX + bouncingRectWidth > centerRectX && 
      bouncingRectX < centerRectX + centerRectWidth && 
      bouncingRectY + bouncingRectHeight + bouncingRectSpeedY > centerRectY && 
      bouncingRectY + bouncingRectSpeedY < centerRectY + centerRectHeight) {
    bouncingRectSpeedY *= -1;
  //bounce off top and bottom edges of screen
  else if(bouncingRectY < 0 || bouncingRectY + bouncingRectHeight > height){
    bouncingRectSpeedY *= -1;
  bouncingRectX += bouncingRectSpeedX;
  bouncingRectY += bouncingRectSpeedY;

  //draw the bouncing rectangle
  rect(bouncingRectX, bouncingRectY, bouncingRectWidth, bouncingRectHeight);
<canvas> </canvas>