RosettaCodeData/Task/Brownian-tree/Scala/brownian-tree.scala
2018-08-17 15:15:24 +01:00

50 lines
1.5 KiB
Scala

import java.awt.Graphics
import java.awt.image.BufferedImage
import javax.swing.JFrame
import scala.collection.mutable.ListBuffer
object BrownianTree extends App {
val rand = scala.util.Random
class BrownianTree extends JFrame("Brownian Tree") with Runnable {
setBounds(100, 100, 400, 300)
val img = new BufferedImage(getWidth, getHeight, BufferedImage.TYPE_INT_RGB)
override def paint(g: Graphics): Unit = g.drawImage(img, 0, 0, this)
override def run(): Unit = {
class Particle(var x: Int = rand.nextInt(img.getWidth),
var y: Int = rand.nextInt(img.getHeight)) {
/* returns false if either out of bounds or collided with tree */
def move: Boolean = {
val (dx, dy) = (rand.nextInt(3) - 1, rand.nextInt(3) - 1)
if ((x + dx < 0) || (y + dy < 0) ||
(y + dy >= img.getHeight) || (x + dx >= img.getWidth)) false
else {
x += dx
y += dy
if ((img.getRGB(x, y) & 0xff00) == 0xff00) {
img.setRGB(x - dx, y - dy, 0xff00)
false
} else true
}
}
}
var particles = ListBuffer.fill(20000)(new Particle)
while (particles.nonEmpty) {
particles = particles.filter(_.move)
repaint()
}
}
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE)
img.setRGB(img.getWidth / 2, img.getHeight / 2, 0xff00)
setVisible(true)
}
new Thread(new BrownianTree).start()
}