/*
size(400,400);

BImage b;
// you can load jpg or gif images - gif will show alpha channel if it has one embedded
b = loadImage("window.jpg");
image(b, 0, 0);
*/

BImage b;
int sizex = 400;
int sizey = 400;

void setup() {
  size(sizex,sizey);
  background(0);
}

void loop() {
  b = loadImage("window.jpg");

  // this translate statement is key because it finds the midpoint of the window
  // if we didn't do this, then the images would rotate about the upper left corner of the screen, not the middle!
  // for more reference, check out this page and scroll down until you see the "Ratation" heading:
  // http://stage.itp.nyu.edu/%7Edts204/ppaint/week3/index.html

  translate (sizex/2, sizey/2);
  tint (200, 200, 255);
  push();
  twirl_image( 20, b, -100, 0, 300, 8);
  pop();
  tint (200, 255, 200);
  twirl_image( 20, b, -50, 0, 40, 20);
}

// by using the following method:
// void function_name ( datatype variablename, etc..)
// { statements }
// ...you can easily trigger a complex event from the main body of your program multiple times

void twirl_image ( int num, BImage img, int xloc, int yloc, int imgsize, int rot) {

  int i=0;
  while (i<num) {

    // the following image command then uses the values that were passed into the function to control how and where the image is drawn
    image(img, xloc, yloc, imgsize, imgsize);

    // in this case i draw one image first, before any other transformations because I want my first image to be straight vertical on the screen
     translate(0,0,-100);

    // radians are the default rotational measurement used by Processing but it is often easier to think in degrees.
    // note - you  can easly convert from degrees to radians by using the radians () command - it does the math for you.
    // for a reminder about radians vs degrees, check out this page: http://aleph0.clarku.edu/~djoyce/java/trig/angle.html
    // you should also know about some numerical constants that are supplied by Processing, however.
    // they are PI, TWO_PI, and HALF_PI. notice that these constants are in all capital letters, a common way of indicating constants in various programming languages.
    rotate (radians (rot));
 
    i = i+1;
  }
}