aho_extra_motion.pde

float x,y;
float dir,dirChange,maxChange,speed;

void setup() {
  size(300,300);
  x=width/2;
  y=height/2;
  
  dir=random(360);

  maxChange=10;
  dirChange=random(-maxChange, maxChange);
  speed=5;
  ellipseMode(CENTER_DIAMETER);
  framerate(25);
}

void loop() {
  background(255,200,0);
  
  // Update direction
  dirChange=dirChange+random(-maxChange/5, maxChange/5);
  if(dirChange<-maxChange) dirChange=-maxChange;
  else if(dirChange>maxChange) dirChange=maxChange;
  
  dir=dir+dirChange;
  x=x+cos(radians(dir))*speed;
  y=y+sin(radians(dir))*speed;
  
  if(x>width) x=0;
  else if(x<0) x=width;
  if(y>width) y=0;
  else if(y<0) y=width;
  
  noFill();
  stroke(100,0,0);
  ellipse(x,y, 30,30);
  fill(100,0,0);
  ellipse(x,y,15,15);
}