From 03642632f55f1d265bf0d02f8e2a430316a96426 Mon Sep 17 00:00:00 2001
From: minebill <minebill@protonmail.com>
Date: Sun, 8 Oct 2023 21:45:34 +0300
Subject: [PATCH] Use a maximum distance between clicks, when detecting a
 double click

---
 Source/Engine/Platform/Linux/LinuxWindow.cpp | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/Source/Engine/Platform/Linux/LinuxWindow.cpp b/Source/Engine/Platform/Linux/LinuxWindow.cpp
index e6fe63f9c..5f8a471b8 100644
--- a/Source/Engine/Platform/Linux/LinuxWindow.cpp
+++ b/Source/Engine/Platform/Linux/LinuxWindow.cpp
@@ -41,8 +41,10 @@ extern Dictionary<StringAnsi, X11::KeyCode> KeyNameMap;
 extern Array<KeyboardKeys> KeyCodeMap;
 extern X11::Cursor Cursors[(int32)CursorType::MAX];
 
-static const uint32 MouseDoubleClickTime = 500;
+static constexpr uint32 MouseDoubleClickTime = 500;
+static constexpr uint32 MaxDoubleClickDistanceSquared = 10;
 static X11::Time MouseLastButtonPressTime = 0;
+static Float2 OldMouseClickPosition;
 
 LinuxWindow::LinuxWindow(const CreateWindowSettings& settings)
 	: WindowBase(settings)
@@ -597,15 +599,19 @@ void LinuxWindow::OnButtonPress(void* event)
 	// Handle double-click
 	if (buttonEvent->button == Button1)
 	{
-		if (buttonEvent->time < (MouseLastButtonPressTime + MouseDoubleClickTime))
+		if (
+			buttonEvent->time < (MouseLastButtonPressTime + MouseDoubleClickTime) &&
+			Float2::DistanceSquared(mousePos, OldMouseClickPosition) < MaxDoubleClickDistanceSquared)
 		{
 			Input::Mouse->OnMouseDoubleClick(ClientToScreen(mousePos), mouseButton, this);
 			MouseLastButtonPressTime = 0;
+			OldMouseClickPosition = mousePos;
 			return;
 		}
 		else
 		{
 			MouseLastButtonPressTime = buttonEvent->time;
+			OldMouseClickPosition = mousePos;
 		}
 	}