From f3a7c6b05df2a5fcde2617cbfcb8ef780989f5b5 Mon Sep 17 00:00:00 2001
From: NathanSweet <nathan.sweet@gmail.com>
Date: Sun, 27 Dec 2020 14:06:08 -0800
Subject: [PATCH] [scene2d.ui] ScrollPane, fixed scrolling via mouse wheel when
 there are scrollbars in only one direction.

---
 .../badlogic/gdx/scenes/scene2d/ui/ScrollPane.java    | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/gdx/src/com/badlogic/gdx/scenes/scene2d/ui/ScrollPane.java b/gdx/src/com/badlogic/gdx/scenes/scene2d/ui/ScrollPane.java
index 969935d9282..fe044c5954c 100644
--- a/gdx/src/com/badlogic/gdx/scenes/scene2d/ui/ScrollPane.java
+++ b/gdx/src/com/badlogic/gdx/scenes/scene2d/ui/ScrollPane.java
@@ -105,7 +105,7 @@ public ScrollPane (@Null Actor widget, ScrollPaneStyle style) {
 		addScrollListener();
 	}
 
-	protected void addCaptureListener() {
+	protected void addCaptureListener () {
 		addCaptureListener(new InputListener() {
 			private float handlePosition;
 
@@ -182,7 +182,7 @@ public boolean mouseMoved (InputEvent event, float x, float y) {
 		});
 	}
 
-	protected ActorGestureListener getFlickScrollListener() {
+	protected ActorGestureListener getFlickScrollListener () {
 		return new ActorGestureListener() {
 			public void pan (InputEvent event, float x, float y, float deltaX, float deltaY) {
 				setScrollbarsVisible(true);
@@ -216,11 +216,16 @@ public boolean handle (Event event) {
 		};
 	}
 
-	protected void addScrollListener() {
+	protected void addScrollListener () {
 		addListener(new InputListener() {
 			public boolean scrolled (InputEvent event, float x, float y, float scrollAmountX, float scrollAmountY) {
 				setScrollbarsVisible(true);
 				if (scrollY || scrollX) {
+					if (scrollY) {
+						if (!scrollX && scrollAmountY == 0) scrollAmountY = scrollAmountX;
+					} else {
+						if (scrollX && scrollAmountX == 0) scrollAmountX = scrollAmountY;
+					}
 					setScrollY(amountY + getMouseWheelY() * scrollAmountY);
 					setScrollX(amountX + getMouseWheelX() * scrollAmountX);
 				} else