Do you want to be painted by ninety-nine evil robots living in your Macintosh™ computer, that has a camera attached to it? If YES then here is something large to click on:

Sorry to all the dozens of fans of embedding applets in actual web pages, on the internet, but this time it was not possible to be so obnoxious. Only the paragon of private and secure browsing, Adobe Flash, is allowed to activate your camera from ‘rich media’ and transmit images back to the mothership.

But this is totally worth the D/L guys! Made with Processing, obviously, and shortly written in Scala:

import processing.video._

size(800, 600)
val video = new Capture(applet, width, height, 6)
smooth()
strokeWeight(8)

// current positions
var pos_list = List[Point]()
keyPressed()
override def keyPressed() {
  pos_list = List.tabulate(99, n => Point(width/2, height/2))
  background(0xFFAAAAAA)
}

// circle of 20 points, radius of 10 with center at 0,0
val r = 10;
val circle = List.tabulate(20, PI*_/10).map( t =>
  Point((cos(t)*r).toInt, (sin(t)*r).toInt)
)

def draw() {
  video.read()
  // if this is a real live frame
  if (video.get(width/2, height/2) != -16777216) {
    pos_list = pos_list.map { pos =>
      val c = video.get(pos.x, pos.y)
      // randomly select next point from circle around current
      // with bias for similar colors and staying in bounds
      val next = play(circle.map { circle_p =>
        val p = pos + circle_p
        (bounds(p) * similarity(c, video.get(p.x, p.y))) %> p
      }: _*)
      stroke(c)
      line(pos.x, pos.y, next.x, next.y)
      next
    }
  }
}

def bounds(p: Point) = if (
  p.x > 0 &&
  p.x < width &&
  p.y > 0 &&
  p.y < height) 1 else 0

def similarity(a: Color, b: Color) =
  1 + 10 / max(1, ((a.r - b.r)*^2 + (a.g - b.g)*^2 + (a.b - b.b)*^2))

case class Point(x: Int, y: Int) {
  def + (o: Point) = Point(x + o.x, y + o.y)
}

Can you spot the sneaky robots’ implicit conversions that access a growing assortment of handy operators?

This application is packaged as an example in Spde.