From d337844b82b79ef9bec7cbffc0b2adf50177fcae Mon Sep 17 00:00:00 2001
From: Michael Gibson <michael.gibson@techcyte.com>
Date: Fri, 28 Feb 2025 16:26:42 -0700
Subject: [PATCH] Pixel density ratio

---
 src/openseadragon.js |  4 ++++
 src/viewer.js        | 10 +++++++++-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/openseadragon.js b/src/openseadragon.js
index 837595aa..348a3192 100644
--- a/src/openseadragon.js
+++ b/src/openseadragon.js
@@ -355,6 +355,9 @@
   *     Specifies the animation duration per each {@link OpenSeadragon.Spring}
   *     which occur when the image is dragged, zoomed or rotated.
   *
+  * @property {Number} [pixelDensityRatio=?]
+  *     When pixelDensityRatio is not provided, it is derived from window.devicePixelRatio
+  *
   * @property {OpenSeadragon.GestureSettings} [gestureSettingsMouse]
   *     Settings for gestures generated by a mouse pointer device. (See {@link OpenSeadragon.GestureSettings})
   * @property {Boolean} [gestureSettingsMouse.dragToPan=true] - Pan on drag gesture
@@ -1275,6 +1278,7 @@ function OpenSeadragon( options ){
             dblClickDistThreshold:  20,
             springStiffness:        6.5,
             animationTime:          1.2,
+            pixelDensityRatio:      null,
             gestureSettingsMouse:   {
                 dragToPan: true,
                 scrollToZoom: true,
diff --git a/src/viewer.js b/src/viewer.js
index 5d2d52bc..42d02750 100644
--- a/src/viewer.js
+++ b/src/viewer.js
@@ -420,6 +420,10 @@ $.Viewer = function( options ) {
         silenceMultiImageWarnings:          this.silenceMultiImageWarnings
     });
 
+    if (this.pixelDensityRatio) {
+        $.pixelDensityRatio = this.pixelDensityRatio;
+    }
+
     this.viewport._setContentBounds(this.world.getHomeBounds(), this.world.getContentFactor());
 
     // Create the image loader
@@ -520,6 +524,7 @@ $.Viewer = function( options ) {
             loadTilesWithAjax: this.loadTilesWithAjax,
             ajaxHeaders:       this.ajaxHeaders,
             ajaxWithCredentials: this.ajaxWithCredentials,
+            pixelDensityRatio: this.pixelDensityRatio,
         });
     }
 
@@ -2581,7 +2586,10 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
      */
      _updatePixelDensityRatio: function() {
         var previusPixelDensityRatio = $.pixelDensityRatio;
-        var currentPixelDensityRatio = $.getCurrentPixelDensityRatio();
+        var currentPixelDensityRatio = this.pixelDensityRatio;
+        if (!currentPixelDensityRatio) {
+            currentPixelDensityRatio = $.getCurrentPixelDensityRatio();
+        }
         if (previusPixelDensityRatio !== currentPixelDensityRatio) {
             $.pixelDensityRatio = currentPixelDensityRatio;
             this.forceResize();