From c750ec3cc7b921cf7d11d4d04a9e0240ebef47f3 Mon Sep 17 00:00:00 2001
From: Cameron Gutman <aicommander@gmail.com>
Date: Wed, 18 May 2022 00:24:58 -0500
Subject: [PATCH] Add workaround for macOS scrolling acceleration

See #778
---
 app/streaming/input/mouse.cpp | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/app/streaming/input/mouse.cpp b/app/streaming/input/mouse.cpp
index 07dc6abd..61ff9ba9 100644
--- a/app/streaming/input/mouse.cpp
+++ b/app/streaming/input/mouse.cpp
@@ -219,6 +219,12 @@ void SdlInputHandler::handleMouseWheelEvent(SDL_MouseWheelEvent* event)
             event->preciseY = -event->preciseY;
         }
 
+#ifdef Q_OS_DARWIN
+        // HACK: Clamp the scroll values on macOS to prevent OS scroll acceleration
+        // from generating wild scroll deltas when scrolling quickly.
+        event->preciseY = SDL_clamp(event->preciseY, -1.0f, 1.0f);
+#endif
+
         LiSendHighResScrollEvent((short)(event->preciseY * 120)); // WHEEL_DELTA
     }
 #else
@@ -228,6 +234,11 @@ void SdlInputHandler::handleMouseWheelEvent(SDL_MouseWheelEvent* event)
             event->y = -event->y;
         }
 
+#ifdef Q_OS_DARWIN
+        // See comment above
+        event->y = SDL_clamp(event->y, -1, 1);
+#endif
+
         LiSendScrollEvent((signed char)event->y);
     }
 #endif