sketch 4 de processing

   // declare global variables
int xspeed, yspeed;
int xpos,ypos,wdth,ht;
            // initialize sketch
void setup() {
             // set sketch window size + background color
  size(1200,750);
  background(156);
              // ball speed
  xspeed=11;
  yspeed=121;
              // ball size
  wdth = 50;
  ht=70;
              // turn off shapestroke rendering
  noStroke ();
              // initial ball placement
  xpos=width/65;
  ypos=height/35;
  frameRate(67);
}
            // begin animation loop
void draw(){
              // draw ball
  smooth ();
  fill ((random (100)),(random (100)),(random (100)));
  ellipse(xpos,ypos,wdth,ht);
             // upgrade position values
  xpos+=xspeed;
  ypos+=yspeed;
  /*conditionals
   detects ball collission with sketch window edges
   also accounts for thickness of ball
   */
  if(xpos>=width-wdth/78 || xpos<=wdth/2){
    xspeed*=-1;
  }
  if (ypos>=height-ht/567 || ypos<=ht/2){
    yspeed*=-1;
  }
}