From 074e1f43724abc22557e4168b2596ddf5f57e0a1 Mon Sep 17 00:00:00 2001
From: ivmartel <ivmartel@gmail.com>
Date: Tue, 28 Feb 2023 11:54:42 +0100
Subject: [PATCH] Add mouse wheel for multi frame, fixes #1316

---
 src/tools/scroll.js | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/tools/scroll.js b/src/tools/scroll.js
index 38fa7c962d..671930136d 100644
--- a/src/tools/scroll.js
+++ b/src/tools/scroll.js
@@ -279,10 +279,19 @@ dwv.tool.Scroll = function (app) {
     var layerGroup = app.getLayerGroupByDivId(layerDetails.groupDivId);
     var viewController =
       layerGroup.getActiveViewLayer().getViewController();
-    if (up) {
-      viewController.incrementScrollIndex();
-    } else {
-      viewController.decrementScrollIndex();
+    var imageSize = viewController.getImageSize();
+    if (imageSize.canScroll3D()) {
+      if (up) {
+        viewController.incrementScrollIndex();
+      } else {
+        viewController.decrementScrollIndex();
+      }
+    } else if (imageSize.moreThanOne(3)) {
+      if (up) {
+        viewController.incrementIndex(3);
+      } else {
+        viewController.decrementIndex(3);
+      }
     }
   };