From 452e50c8d8780ecb2c866282ec1b819f076a0370 Mon Sep 17 00:00:00 2001
From: Ian Gilman <ian@iangilman.com>
Date: Tue, 3 Jul 2018 09:40:10 -0700
Subject: [PATCH 1/2] Making the DziTileSource honor minLevel.

---
 src/dzitilesource.js | 4 ++++
 src/tiledimage.js    | 1 +
 2 files changed, 5 insertions(+)

diff --git a/src/dzitilesource.js b/src/dzitilesource.js
index ec5ea9a9..ee862f0d 100644
--- a/src/dzitilesource.js
+++ b/src/dzitilesource.js
@@ -182,6 +182,10 @@ $.extend( $.DziTileSource.prototype, $.TileSource.prototype, /** @lends OpenSead
             yMax,
             i;
 
+        if ((this.minLevel && level < this.minLevel) || (this.maxLevel && level > this.maxLevel)) {
+            return false;
+        }
+
         if ( !rects || !rects.length ) {
             return true;
         }
diff --git a/src/tiledimage.js b/src/tiledimage.js
index 6fb68413..563dfc89 100644
--- a/src/tiledimage.js
+++ b/src/tiledimage.js
@@ -972,6 +972,7 @@ $.extend($.TiledImage.prototype, $.EventSource.prototype, /** @lends OpenSeadrag
 
         // Calculations for the interval of levels to draw
         // can return invalid intervals; fix that here if necessary
+        highestLevel = Math.max(highestLevel, this.source.minLevel);
         lowestLevel = Math.min(lowestLevel, highestLevel);
         return {
             lowestLevel: lowestLevel,

From 071b8657651a0585b260b64aa356ca63c816463f Mon Sep 17 00:00:00 2001
From: Ian Gilman <ian@iangilman.com>
Date: Fri, 6 Jul 2018 13:17:46 -0700
Subject: [PATCH 2/2] Tweaks to minLevel DZI patch

---
 changelog.txt     | 3 ++-
 src/tiledimage.js | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/changelog.txt b/changelog.txt
index e2eceb7a..302b3702 100644
--- a/changelog.txt
+++ b/changelog.txt
@@ -19,7 +19,8 @@ OPENSEADRAGON CHANGELOG
 * You can now prevent canvas-drag events on the navigator (#1484)
 * You can now prevent canvas-click events on the navigator (#1416)
 * The navigator can now be restricted to just horizontal or just vertical panning (#1416)
-
+* Fixed DziTileSource so it doesn't load levels above maxLevel or below minLevel, if set (#1492)
+ 
 2.3.1:
 
 * Debug mode now uses different colors for different tiled images (customizable via debugGridColor) (#1271)
diff --git a/src/tiledimage.js b/src/tiledimage.js
index 563dfc89..52012071 100644
--- a/src/tiledimage.js
+++ b/src/tiledimage.js
@@ -972,7 +972,7 @@ $.extend($.TiledImage.prototype, $.EventSource.prototype, /** @lends OpenSeadrag
 
         // Calculations for the interval of levels to draw
         // can return invalid intervals; fix that here if necessary
-        highestLevel = Math.max(highestLevel, this.source.minLevel);
+        highestLevel = Math.max(highestLevel, this.source.minLevel || 0);
         lowestLevel = Math.min(lowestLevel, highestLevel);
         return {
             lowestLevel: lowestLevel,