Game of Life in Scala

archive/s/scala/README.md

@@ -6,6 +6,7 @@ Welcome to Sample Programs in Scala!
 
 - [Hello World in Scala][1]
 - [Fizz Buzz in Scala][2]
+- [Game of Life in Scala](https://github.com/TheRenegadeCoder/sample-programs/issues/1035)
 
 ## Fun Facts
 
@@ -25,4 +26,4 @@ Welcome to Sample Programs in Scala!
 [3]: https://en.wikipedia.org/wiki/Scala_(programming_language)
 [4]: https://www.scala-lang.org
 [5]: https://github.com/scala/scala
-[6]: https://scastie.scala-lang.org
+[6]: https://scastie.scala-lang.org

archive/s/scala/game-of-life.scala

@@ -0,0 +1,153 @@
+import javax.swing._;
+import java.awt.Dimension;
+import java.awt.GridLayout;
+import java.awt.Color;
+
+import scala.util.Try
+
+class Cell(var isAlive: Boolean) extends JPanel {
+  var neighbors = Array[Cell]()
+  var wasAlive: Boolean = isAlive
+  this.updateBackground
+
+  def updateBackground() {
+    val color: Color = if (this.isAlive) Color.BLACK else Color.WHITE
+    this.setBackground(color)
+  }
+
+  def addNeighbor(neighbor: Cell) {
+    this.neighbors = this.neighbors :+ neighbor
+  }
+
+  def clearState() {
+    this.wasAlive = this.isAlive
+  }
+
+  def countLivingNeighbors(): Int = this.neighbors.filter(n => n.wasAlive == true).length
+
+  def transition() {
+    val count = this.countLivingNeighbors
+    if (this.wasAlive) {
+      this.isAlive = count match {
+        case c if c == 2 || c == 3 => true
+        case _ => false
+      }
+    } else if (count == 3) {
+      this.isAlive = true
+    }
+  }
+}
+
+class Grid (width: Int, var spawnRate: Double) extends JPanel {
+  this.setMinimumSize(new Dimension(width, width));
+  this.setMaximumSize(new Dimension(width, width));
+  this.setPreferredSize(new Dimension(width, width));
+
+  var grid = Array.ofDim[Cell](width, width)
+  this.setLayout(new GridLayout(width, width))
+
+  def populate() {
+    for (row <- 0 to this.grid.length - 1) {
+      for (col <- 0 to this.grid(row).length - 1) {
+        val rand: Boolean = Math.random < spawnRate
+        this.grid(row)(col) = new Cell(rand)
+        this.add(this.grid(row)(col))
+      }
+    }
+  }
+
+  def link() {
+    for (row <- 0 to this.grid.length - 1) {
+      for (col <- 0 to this.grid(row).length - 1) {
+        val prevRow: Int = Math.floorMod((row - 1), this.width)
+        val nextRow: Int = Math.floorMod((row + 1), this.width)
+        val prevCol: Int = Math.floorMod((col - 1), this.width)
+        val nextCol: Int = Math.floorMod((col + 1), this.width)
+        this.grid(row)(col).addNeighbor(this.grid(row)(prevCol));
+        this.grid(row)(col).addNeighbor(this.grid(row)(nextCol));
+        this.grid(row)(col).addNeighbor(this.grid(nextRow)(col));
+        this.grid(row)(col).addNeighbor(this.grid(prevRow)(col));
+        this.grid(row)(col).addNeighbor(this.grid(prevRow)(prevCol));
+        this.grid(row)(col).addNeighbor(this.grid(prevRow)(nextCol));
+        this.grid(row)(col).addNeighbor(this.grid(nextRow)(prevCol));
+        this.grid(row)(col).addNeighbor(this.grid(nextRow)(nextCol));
+      }
+    }
+  }
+
+  def generate() {
+    this.populate
+    this.link
+  }
+
+  def step() {
+    for (row <- 0 to this.grid.length - 1) {
+      for (col <- 0 to this.grid(row).length - 1) {
+        this.grid(row)(col).transition
+        this.grid(row)(col).updateBackground
+      }
+    }
+    for (row <- 0 to this.grid.length - 1) {
+      for (col <- 0 to this.grid(row).length - 1) {
+        this.grid(row)(col).clearState
+      }
+    }
+  }
+}
+
+// default configs
+class Game (
+  var width: Int = 100,
+  var frameRate: Double = 3.0,
+  var totalFrames: Int = 200,
+  var spawnRate: Double = 0.15
+) {
+
+  // additional config helpers receiving from IO
+  def config(width: Int, frameRate: Double, totalFrames: Int, spawnRate: Double) = {
+    this.width = width
+    this.frameRate = frameRate
+    this.totalFrames = totalFrames
+    this.spawnRate = spawnRate
+  }
+
+  def run() {
+    val frame = new JFrame("Game of Life - a Scala port")
+    var grid = new Grid(this.width, this.spawnRate)
+    grid.generate
+    frame.getContentPane().add(grid)
+    frame.pack
+    frame.setVisible(true)
+
+    for (i <- 0 to this.totalFrames) {
+      try {
+        val delay: Int = (1000 / this.frameRate).toInt
+        Thread.sleep(delay)
+      }
+      catch {
+        case e: InterruptedException => Thread.currentThread().interrupt
+      }
+      grid.step
+    }
+  }
+}
+
+object GameOfLife {
+  def main(args: Array[String]) {
+    // parse args
+    val game = new Game
+    // fail silently and use game default configs
+    if (args.length > 3) {
+      Try {
+        val width: Int = args(0).toInt
+        val frameRate: Double = args(1).toDouble
+        val totalFrames: Int = args(2).toInt
+        val spawnRate: Double = args(3).toDouble
+
+        game.config(width, frameRate, totalFrames, spawnRate)
+      }
+    }
+
+    game.run
+  }
+}