From 5b7552216dbfd0aaa73b83b14edc18c8785e75f5 Mon Sep 17 00:00:00 2001
From: Marty Oehme <marty.oehme@gmail.com>
Date: Fri, 20 Jul 2018 14:36:32 +0200
Subject: [PATCH] Game - Add Color Oscillation

---
 lib/game/Game.dart | 29 +++++++++++++++++++++++------
 1 file changed, 23 insertions(+), 6 deletions(-)

diff --git a/lib/game/Game.dart b/lib/game/Game.dart
index 7291f59..1c16c5d 100644
--- a/lib/game/Game.dart
+++ b/lib/game/Game.dart
@@ -1,21 +1,29 @@
 import 'dart:html';
 
+import 'dart:math';
+
 typedef void gridIterator(int x, int y);
 
 class Game {
   List<List<Color>> grid;
   CanvasElement canvas;
   CanvasRenderingContext2D ctx;
+  Random rng = new Random();
 
-  double _oscill = 0.0;
+  double _oscill = 0.1;
+  bool _oscillDir = true; // oscillate upwards (true) or downwards (false)
+  double _OSCILLSPEED = 0.05;
   bool _fwd = true;
 
   Game(CanvasElement this.canvas) {
-    grid = buildGrid(5,5, new Color(255, 100, 255));
+    grid = buildGrid(5, 5, new Color(255, 0, 255));
     ctx = this.canvas.getContext('2d');
   }
 
-  void update([num dt]) {}
+  void update([num dt]) {
+    int ry = rng.nextInt(grid.length);
+    grid[ry][rng.nextInt(grid[ry].length)] = new Color(rng.nextInt(255), rng.nextInt(255), rng.nextInt(255));
+  }
 
   void draw([num interp]) {
     int brickW = (canvas.width ~/ grid[0].length);
@@ -23,13 +31,22 @@ class Game {
 
     ctx.clearRect(0, 0, canvas.width, canvas.height);
     grid_foreach((x, y) {
-        Color col = grid[y][x];
-        ctx.setFillColorRgb(col.r+_oscill, col.g+_oscill, col.b+_oscill);
+        Color col = _oscillate(grid[y][x]);
+        ctx.setFillColorRgb(col.r, col.g, col.b);
         ctx.fillRect(x*brickW, y*brickH, brickW, brickH);
     });
   }
 
-  Color _oscillate(Color) {}
+  Color _oscillate(Color col) {
+    if(_oscill >= 50.0 || _oscill <= -50.0) {
+      _oscillDir = !_oscillDir;
+      _oscill = max( min(_oscill, 49.0), -49.0);
+    }
+    else _oscillDir == true ? _oscill += _OSCILLSPEED : _oscill -= _OSCILLSPEED;
+
+    int o = _oscill.toInt();
+    return new Color(col.r + o, col.g + o, col.b + o);
+  }
 
   void grid_foreach(gridIterator fun) {
     for (int y = 0; y < grid.length; y++) {