Animation animation1, animation2;
float xpos, ypos;
float drag = 80.0;

void setup() {
  size(250, 220);
  colorMode (RGB, 100);
  frameRate(11);
  animation1 = new Animation("PT_Ama_", 33);
  animation2 = new Animation("PT_Pet_", 33);
}

void draw() { 

  float difx = mouseX - xpos;
  if (abs(difx) > 1.0) {
    xpos = xpos + difx/drag;
    xpos = constrain(xpos, 30,70 );
  }
  float dify = mouseY - ypos;
  if (abs(dify) > 1.0) {
    ypos = ypos + difx/drag;
    ypos = constrain(ypos, 10,  50);
  }

  // Display the sprite at the position xpos, ypos
  if (mousePressed) {
    animation1.display(xpos-animation1.getWidth()/8, ypos/4);
  } 
  else {
    animation2.display(xpos-animation1.getHeight()/8, ypos/4);


  }

}

// Class for animating a sequence of GIFs

class Animation {
  PImage[] images;
  int imageCount;
  int frame;

  Animation(String imagePrefix, int count) {
    imageCount = count;
    images = new PImage[imageCount];

    for (int i = 0; i < imageCount; i++) {
      // Use nf() to number format 'i' into four digits
      String filename = imagePrefix + nf(i, 4) + ".jpg";
      images[i] = loadImage(filename);
    }
  }

  void display(float xpos, float ypos) {
    frame = (frame+1) % imageCount;
    image(images[frame], xpos, ypos);

    rect (0, 0, width,height );
    fill(238, 238, 238,  (frame+1));
    stroke(255);
  }

  int getWidth() {
    return images[0].width;
  }

  int getHeight() {
    return images[0].height;
  }
}