From f51658f0af5483aae24e39e92216a768fac86c6f Mon Sep 17 00:00:00 2001
From: Alexey Tikhonov <altertt@gmail.com>
Date: Tue, 23 Feb 2016 20:42:21 +0300
Subject: [PATCH] don't draw tiles with opacity 0, see #806

---
 src/tiledimage.js | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/tiledimage.js b/src/tiledimage.js
index 7772c186..7499e169 100644
--- a/src/tiledimage.js
+++ b/src/tiledimage.js
@@ -240,9 +240,11 @@ $.extend($.TiledImage.prototype, $.EventSource.prototype, /** @lends OpenSeadrag
      * Draws the TiledImage to its Drawer.
      */
     draw: function() {
-        this._midDraw = true;
-        updateViewport( this );
-        this._midDraw = false;
+        if (this.opacity !== 0) {
+            this._midDraw = true;
+            updateViewport( this );
+            this._midDraw = false;
+        }
     },
 
     /**