From ff22c8ac3b6edff9231165bb06921a39ad273bf2 Mon Sep 17 00:00:00 2001
From: LynithDev <61880709+LynithDev@users.noreply.github.com>
Date: Wed, 19 Aug 2026 15:07:15 +0200
Subject: [PATCH] fix(app): normalize trackpad scroll deltas on macOS (#694)

---
 .../src/components/scrollview.rs              | 42 ++++++++++++++++---
 1 file changed, 36 insertions(+), 6 deletions(-)

diff --git a/packages/oneclient_app/src/components/scrollview.rs b/packages/oneclient_app/src/components/scrollview.rs
index 8b573159..46978be6 100644
--- a/packages/oneclient_app/src/components/scrollview.rs
+++ b/packages/oneclient_app/src/components/scrollview.rs
@@ -5,6 +5,30 @@ use crate::theme::colors;
 
 const LAZY_OVERSCAN: i64 = 3;
 
+pub(crate) fn normalize_wheel_delta(delta: f64, scale_factor: f64) -> f32 {
+    if delta == 0.0 {
+        return 0.0;
+    }
+
+	const FREYA_LINE_SPEED: f64 = 53.0;
+	const FREYA_PIXEL_SPEED: f64 = 2.0;
+	const LINE_DELTA_TOLERANCE: f64 = 1e-6;
+	const LINE_SCROLL: f64 = 53.0;
+	const PIXEL_SCROLL: f64 = 1.0;
+
+    let lines = (delta / FREYA_LINE_SPEED).round();
+    if lines != 0.0 && (delta - lines * FREYA_LINE_SPEED).abs() <= LINE_DELTA_TOLERANCE {
+        return (lines * LINE_SCROLL) as f32;
+    }
+
+    let scale_factor = if scale_factor > 0.0 {
+        scale_factor
+    } else {
+        1.0
+    };
+    (delta / (FREYA_PIXEL_SPEED * scale_factor) * PIXEL_SCROLL) as f32
+}
+
 pub(crate) fn scroll_pos_from_wheel(wheel: f32, inner: f32, viewport: f32, current: f32) -> i32 {
     if viewport >= inner {
         return 0;
@@ -226,6 +250,8 @@ impl ScrollArea {
         let internal = use_scroll_controller(ScrollConfig::default);
         let mut controller = self.controller.unwrap_or(internal);
 
+        let scale_factor = Platform::get().scale_factor;
+
         let mut viewport_h = use_state(|| 0f32);
         let mut viewport_w = use_state(|| 0f32);
         let mut viewport_top = use_state(|| 0f32);
@@ -310,17 +336,21 @@ impl ScrollArea {
 
         let on_wheel = move |e: Event<WheelEventData>| {
             let shift = *shift_held.read();
+            let scale = *scale_factor.peek();
+
+            let delta_x = normalize_wheel_delta(e.delta_x, scale);
+            let delta_y = normalize_wheel_delta(e.delta_y, scale);
 
             let h_delta = if horizontal {
-                if shift && e.delta_x == 0.0 {
-                    e.delta_y
+                if shift && delta_x == 0.0 {
+                    delta_y
                 } else {
-                    e.delta_x
+                    delta_x
                 }
             } else {
                 0.0
             };
-            let v_delta = if horizontal && shift { 0.0 } else { e.delta_y };
+            let v_delta = if horizontal && shift { 0.0 } else { delta_y };
 
             let do_h = h_delta != 0.0 && can_scroll_h;
             let do_v = v_delta != 0.0 && can_scroll_v;
@@ -337,14 +367,14 @@ impl ScrollArea {
 
             if do_h {
                 let cur_x = corrected_scroll(content_w, vp_w, *scroll_x.read());
-                let new_x = scroll_pos_from_wheel(h_delta as f32, content_w, vp_w, cur_x);
+                let new_x = scroll_pos_from_wheel(h_delta, content_w, vp_w, cur_x);
                 scroll_x.set(new_x as f32);
             }
 
             if do_v {
                 let (_, cur_y) = controller.into();
                 let current = corrected_scroll(ct_h, vp_h, cur_y as f32);
-                let new_y = scroll_pos_from_wheel(v_delta as f32, ct_h, vp_h, current);
+                let new_y = scroll_pos_from_wheel(v_delta, ct_h, vp_h, current);
                 if new_y != cur_y {
                     controller.scroll_to_y(new_y);
                 }