implemented zooming

src/main.js

@@ -46,7 +46,8 @@ class Demo {
 	}
 
 	draw(context) {
-		this.map.forEach(cell => this[cell.tile][cell.style](context, cell));
+		let scale = 1;
+		this.map.forEach(cell => this[cell.tile][cell.style](context, scale, cell.x, cell.y, cell));
 	}
 }