// The function 'droste()' recursively draws an image
// over itself, as on the famous Droste chocolate box.
// The arguments (tx,ty) tells where on the image a
// smaller image must be duplicated, and argument s
// tells how much smaller each subsequent image is.
// Argument d tells how deep the recursion continues.
//
// Concept and code by Joris Slob and Maarten Lamers,
// 2007.

void setup() {  
  PImage m = loadImage("droste2.jpg");
  size(m.width, m.height);
  droste(m, 13, 235, 0.22, 4);
}

void draw() {
}

void droste (PImage i, int tx, int ty, float s, int d) {
  // Draw image i recursively d times, translating
  // along (tx,ty) and scaling with factor s at each
  // subsequent recursion.
  if (d > 0) {
    image(i, 0, 0);
    translate(tx, ty);
    scale(s);
    droste(i, tx, ty, s, d-1);
  }
}