From 9271198f64cb59272cf20488eba74f833ccc1eed Mon Sep 17 00:00:00 2001
From: Vicki Pfau <vi@endrift.com>
Date: Thu, 19 Sep 2024 00:05:58 -0700
Subject: [PATCH] Qt: Make window corners square on Windows 11 (fixes #3285)

---
 CHANGES                        | 1 +
 src/platform/qt/CMakeLists.txt | 3 ++-
 src/platform/qt/Window.cpp     | 9 +++++++++
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/CHANGES b/CHANGES
index e1e590519..d2e2371d0 100644
--- a/CHANGES
+++ b/CHANGES
@@ -17,6 +17,7 @@ Other fixes:
  - Qt: Fix LCDC background priority/enable bit being mis-mapped in I/O view
  - Updater: Fix updating appimage across filesystems
 Misc:
+ - Qt: Make window corners square on Windows 11 (fixes mgba.io/i/3285)
  - Switch: Add bilinear filtering option (closes mgba.io/i/3111)
  - Vita: Add imc0 and xmc0 mount point support
 
diff --git a/src/platform/qt/CMakeLists.txt b/src/platform/qt/CMakeLists.txt
index d26b5701a..5a56f775d 100644
--- a/src/platform/qt/CMakeLists.txt
+++ b/src/platform/qt/CMakeLists.txt
@@ -387,6 +387,7 @@ set_target_properties(${BINARY_NAME}-qt PROPERTIES MACOSX_BUNDLE_INFO_PLIST ${CM
 
 if(WIN32)
 	set_target_properties(${BINARY_NAME}-qt PROPERTIES RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}")
+	target_link_libraries(${BINARY_NAME}-qt dwmapi)
 	if(NOT MSVC)
 		target_link_libraries(${BINARY_NAME}-qt -municode)
 	endif()
@@ -402,7 +403,7 @@ if(QT_STATIC)
 		if(CMAKE_CROSSCOMPILING)
 			set(QWINDOWS_DEPS ${QT}EventDispatcherSupport ${QT}FontDatabaseSupport ${QT}ThemeSupport ${QT}WindowsUIAutomationSupport)
 		endif()
-		list(APPEND QT_LIBRARIES ${QT}::QWindowsIntegrationPlugin ${QWINDOWS_DEPS} amstrmid dwmapi uxtheme imm32 -static-libgcc -static-libstdc++)
+		list(APPEND QT_LIBRARIES ${QT}::QWindowsIntegrationPlugin ${QWINDOWS_DEPS} amstrmid uxtheme imm32 -static-libgcc -static-libstdc++)
 		set_target_properties(${QT}::Core PROPERTIES INTERFACE_LINK_LIBRARIES "${QTPCRE};version;winmm;ssl;crypto;ws2_32;iphlpapi;crypt32;userenv;netapi32;wtsapi32")
 		set_target_properties(${QT}::Gui PROPERTIES INTERFACE_LINK_LIBRARIES ${OPENGL_LIBRARY} ${OPENGLES2_LIBRARY})
 	elseif(APPLE)
diff --git a/src/platform/qt/Window.cpp b/src/platform/qt/Window.cpp
index 4a16c73bb..54a69ecf8 100644
--- a/src/platform/qt/Window.cpp
+++ b/src/platform/qt/Window.cpp
@@ -14,6 +14,10 @@
 #include <QScreen>
 #include <QWindow>
 
+#ifdef Q_OS_WIN
+#include <dwmapi.h>
+#endif
+
 #ifdef USE_SQLITE3
 #include "ArchiveInspector.h"
 #include "library/LibraryController.h"
@@ -745,6 +749,11 @@ void Window::showEvent(QShowEvent* event) {
 		return;
 	}
 	m_wasOpened = true;
+#ifdef Q_OS_WIN
+	HWND hwnd = reinterpret_cast<HWND>(winId());
+	DWM_WINDOW_CORNER_PREFERENCE cornerPref = DWMWCP_DONOTROUND;
+	DwmSetWindowAttribute(hwnd, DWMWA_WINDOW_CORNER_PREFERENCE, &cornerPref, sizeof(cornerPref));
+#endif
 	if (m_initialSize.isValid()) {
 		resizeFrame(m_initialSize);
 	}