From c619fa9f1f5eaaa60eea0f08770a04e703e51115 Mon Sep 17 00:00:00 2001
From: ruevs <dpr@ruevs.com>
Date: Mon, 7 Oct 2024 09:49:11 +0300
Subject: [PATCH] GTK: Fix wrong direction of zoom when "smooth scrolling" with
 mouse wheel

... on Linux/GTK

The bug was introduced here 31d0c27ecdc4ace0a1793191629d258cbd861826
https://github.com/solvespace/solvespace/pull/1464
https://github.com/solvespace/solvespace/pull/1470

Fixes #1488
---
 src/platform/guigtk.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/platform/guigtk.cpp b/src/platform/guigtk.cpp
index 89a29d94a..8e2d38b7b 100644
--- a/src/platform/guigtk.cpp
+++ b/src/platform/guigtk.cpp
@@ -578,7 +578,7 @@ class GtkGLWidget : public Gtk::GLArea {
 //        gdk_scroll_event_get_direction((GdkEvent*)gdk_event, &dir);
 
         if(gdk_event_get_scroll_deltas((GdkEvent*)gdk_event, &dx, &dy)) {
-            delta = dy;
+            delta = -dy;
         } else if(gdk_event_get_scroll_direction((GdkEvent*)gdk_event, &dir)) {
             if(dir == GDK_SCROLL_UP) {
                 delta = 1;