From dd8baa16398309b5315a91ea569a2bfe718c53c1 Mon Sep 17 00:00:00 2001
From: Grant Echols <gechols@ldschurch.org>
Date: Fri, 11 Sep 2015 14:24:22 -0600
Subject: [PATCH] Added 'tile-open-failed' event to notify the app when a tile
 fails to load. This can happen when the image has authentication or other
 restrictions.

---
 src/tiledimage.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/tiledimage.js b/src/tiledimage.js
index 4aaef1db..70772292 100644
--- a/src/tiledimage.js
+++ b/src/tiledimage.js
@@ -1023,6 +1023,18 @@ function loadTile( tiledImage, tile, time ) {
 function onTileLoad( tiledImage, tile, time, image, errorMsg ) {
     if ( !image ) {
         $.console.log( "Tile %s failed to load: %s - error: %s", tile, tile.url, errorMsg );
+        /**
+         * Triggered when a tile fails to load.
+         *
+         * @event tile-open-failed
+         * @memberof OpenSeadragon.Viewer
+         * @type {object}
+         * @property {OpenSeadragon.TiledImage} tiledImage - The tiled image of the unloaded tile.
+         * @property {OpenSeadragon.Tile} tile - The tile which has been unloaded.
+         * @property {number} time - The current time in milliseconds when the tile load began.
+         * @property {string} message - The error message.
+         */
+        tiledImage.viewer.raiseEvent("tile-open-failed", {tile: tile, tiledImage: tiledImage, time: time, message: errorMsg});
         if( !tiledImage.debugMode ){
             tile.loading = false;
             tile.exists = false;