Merge pull request #15319 from Snuffleupagus/bug-1784850

Refresh the viewer if the window resolution changes (bug 1784850)

web/app.js

@@ -2004,6 +2004,27 @@ const PDFViewerApplication = {
   bindWindowEvents() {
     const { eventBus, _boundEvents } = this;
 
+    function addWindowResolutionChange(evt = null) {
+      if (evt) {
+        webViewerResolutionChange(evt);
+      }
+      const mediaQueryList = window.matchMedia(
+        `(resolution: ${window.devicePixelRatio || 1}dppx)`
+      );
+      mediaQueryList.addEventListener("change", addWindowResolutionChange, {
+        once: true,
+      });
+
+      if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("MOZCENTRAL")) {
+        return;
+      }
+      _boundEvents.removeWindowResolutionChange ||= function () {
+        mediaQueryList.removeEventListener("change", addWindowResolutionChange);
+        _boundEvents.removeWindowResolutionChange = null;
+      };
+    }
+    addWindowResolutionChange();
+
     _boundEvents.windowResize = () => {
       eventBus.dispatch("resize", { source: window });
     };
@@ -2123,6 +2144,7 @@ const PDFViewerApplication = {
       _boundEvents.windowUpdateFromSandbox
     );
 
+    _boundEvents.removeWindowResolutionChange?.();
     _boundEvents.windowResize = null;
     _boundEvents.windowHashChange = null;
     _boundEvents.windowBeforePrint = null;
@@ -2689,6 +2711,10 @@ function webViewerPageChanging({ pageNumber, pageLabel }) {
   }
 }
 
+function webViewerResolutionChange(evt) {
+  PDFViewerApplication.pdfViewer.refresh();
+}
+
 function webViewerVisibilityChange(evt) {
   if (document.visibilityState === "visible") {
     // Ignore mouse wheel zooming during tab switches (bug 1503412).

web/base_viewer.js

@@ -2247,6 +2247,17 @@ class BaseViewer {
     }
     this.#annotationEditorUIManager.updateParams(type, value);
   }
+
+  refresh() {
+    if (!this.pdfDocument) {
+      return;
+    }
+    const updateArgs = {};
+    for (const pageView of this._pages) {
+      pageView.update(updateArgs);
+    }
+    this.update();
+  }
 }
 
 export { BaseViewer, PagesCountLimit, PDFPageViewBuffer };