Added effects SingleDynamic and MultiDynamic.

effects.h

@@ -266,3 +266,33 @@ class Animation : public Effect {
       return animation->delays[0];
     }
 };
+
+class SingleDynamic : public Effect {
+  protected:
+    static const int factor = 2;
+    static const int tile_count = LED_WIDTH/factor * LED_HEIGHT/factor;
+    CRGB tiles[tile_count];
+  public:
+    SingleDynamic() {
+      for (int i=0; i<tile_count; i++) tiles[i] = CHSV(random8(), 120, 255);
+    }
+    virtual void update() {
+      tiles[random8() % tile_count] = CHSV(random8(), 120, 255);
+    }
+    boolean can_be_shown_with_clock() { return true; }
+    void loop() {
+      EVERY_N_MILLISECONDS(400) { update(); }
+      
+      for (int x=0; x<window.w; x++) for (int y=0; y<window.h; y++) {
+        int index = y/2 * window.w/2 + x/2;
+        setPixel(window, x, y, tiles[index]);
+      }
+    }
+};
+
+class MultiDynamic : public SingleDynamic {
+  public:
+    void update() {
+      for (int i=0; i<tile_count; i++) tiles[i] = CHSV(random8(), 120, 255);
+    }
+};