PImage[] imgs = new PImage[4]; // loaded images
PImage img;                    // current image
int curImg = 0;                // current image

void setup() 
{
  size(300,450);
  smooth();
  background(0);
  rectMode(CENTER);

  for(int i = 0; i < imgs.length; i ++) imgs[i] = loadImage("img-"+(i+1)+".jpg");
  img = imgs[curImg];
}

void draw() {
  background(0);
  
  // get the tile size
  float s = map(mouseX,0,width,2,12);
  
  // draw a rect mosaic
  noStroke();
  for (float y = s/2; y < img.height; y += s+1) {
    for (float x = s/2; x < img.width; x += s+1) {
      fill(img.get(int(x),int(y)));
      rect(x,y,s,s);
    }
  }
}

void keyPressed() {
  if(key == ' ') {
    curImg = (curImg+1)%imgs.length;
    img = imgs[curImg];
  }
}

// START NO NOTES
// code used to capture screenshots
void keyReleased() {
  if(key == '`' && !online) save("sketch.png");
}