/* built with Studio Sketchpad: 
 *   https://sketchpad.cc
 * 
 * observe the evolution of this sketch: 
 *   https://studio.sketchpad.cc/sp/pad/view/ro.uz3P5vm4N5i/rev.26
 * 
 * authors: 
 *   GoToLoop

 * license (unless otherwise specified): 
 *   creative commons attribution-share alike 3.0 license.
 *   https://creativecommons.org/licenses/by-sa/3.0/ 
 */ 



/**
 * Ball in the Chamber (v2.04)
 * by  Rareware0192 (2015-May-06)
 * Mod GoToLoop (2015-May-07)
 *
 * Forum.Processing.org/two/discussion/10680/collision-colors
 * Studio.ProcessingTogether.com/sp/pad/export/ro.9qPrLGrYGkr2o
 * Bl.ocks.org/GoSubRoutine/d0b7d3058d84970e83cf8685f8e69777
 */

static final int BALLS = 4;
final Ball[] balls = new Ball[BALLS];

static final int CHAMBERS = 8;
final Chamber[] chambers = new Chamber[CHAMBERS];

void setup() {
  size(640, 440);

  smooth(3);
  frameRate(60);

  ellipseMode(CENTER);
  rectMode(CORNER);

  strokeWeight(Ball.BOLD);
  stroke(Ball.STROKE);

  balls[0] = new Ball(50, 50, 4, 2);
  balls[1] = new Ball(50, 80, 3, 5);
  balls[2] = new Ball(100, 150, 4, 5);
  balls[3] = new Ball(300, 300, 6, 2);

  chambers[0] = new Chamber(000, 000, #FF0000); // red
  chambers[1] = new Chamber(600, 000, #00FF00); // green
  chambers[2] = new Chamber(000, 400, #0000FF); // blue
  chambers[3] = new Chamber(600, 400, #FF00FF); // pink
  chambers[4] = new Chamber(300, 000, #FFFF00); // yellow
  chambers[5] = new Chamber(300, 400, #00FFFF); // cyan
  chambers[6] = new Chamber(000, 200, #FA9600); // orange
  chambers[7] = new Chamber(600, 200, #A100FA); // purple
}

void draw() {
  background(0350);

  for (final Ball b : balls) {
    for (final Chamber c : chambers)  if (b.colliding(c)) {
      b.c = c.c;
      break;
    }

    b.script();
  }

  for (final Chamber c : chambers)  c.display();
}

static final int sq(final int n) {
  return n*n;
}

class Ball {
  static final short DIM = 25, RAD = DIM >> 1;
  static final short BOLD = 2;
  static final color STROKE = 0;

  int x, y, vx, vy;
  color c = -1;

  Ball(int x$, int y$, int vx$, int vy$) {
    x = x$;
    y = y$;
    vx = vx$;
    vy = vy$;
  }

  void script() {
    update();
    display();
  }

  void update() {
    if ((x += vx) > width  - RAD | x < RAD)  vx *= -1;
    if ((y += vy) > height - RAD | y < RAD)  vy *= -1;
  }

  void display() {
    fill(c);
    ellipse(x, y, DIM, DIM);
  }

  boolean colliding(final Chamber c) {
    return sq(c.x + Chamber.RAD - x) + sq(c.y + Chamber.RAD - y)
      < sq(Chamber.RAD + RAD);
  }
}

class Chamber {
  static final short DIM = 40, RAD = DIM >> 1;
  static final short BOLD = 2;
  static final color STROKE = 0;

  final int x, y;
  final color c;

  Chamber(int x$, int y$, color c$) {
    x = x$;
    y = y$;
    c = c$;
  }

  void display() {
    fill(c);
    rect(x, y, DIM, DIM);
  }
}