PImage leafImage; //define an image object
PImage myBackImage; //define an image object
void setup(){
  leafImage = loadImage("maple_leaf.gif"); //load it
  myBackImage = loadImage("ground.jpg"); //load it
  size(myBackImage.width,myBackImage.height);
}
int x, y; //the location of the cursor
void draw(){
  image(myBackImage,0,0); //draw the ground
  image(leafImage,x,y); //then the leaf
  x += int(random(-5,5)); //random tremblings
  y += int(random(-5,5));
}
void mouseDragged(){
  x = mouseX-(leafImage.width/2); //move the cursor
  y = mouseY-(leafImage.height/2);
}