Remove rounded corners on Windows 11

projects/cxbx/CMakeLists.txt

@@ -46,7 +46,7 @@ if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
   # Enable Chihiro work
   CHIHIRO_WORK
  )
- 
+
  # Reference: https://docs.microsoft.com/en-us/cpp/build/reference/compiler-options-listed-alphabetically
  add_compile_options(
   # Catch synchronous (C++) exceptions only
@@ -68,7 +68,7 @@ XXH_INLINE_ALL
 )
 
 file (GLOB RESOURCES
- 
+
  "${CXBXR_ROOT_DIR}/CONTRIBUTORS"
  "${CXBXR_ROOT_DIR}/COPYING"
  "${CXBXR_ROOT_DIR}/README.md"
@@ -90,7 +90,7 @@ source_group(TREE ${CXBXR_ROOT_DIR}/import PREFIX import FILES
  ${CXBXR_SOURCE_EMU_IMPORT}
 )
 
-source_group(TREE ${CXBXR_ROOT_DIR}/src PREFIX source FILES 
+source_group(TREE ${CXBXR_ROOT_DIR}/src PREFIX source FILES
  ${CXBXR_SOURCE_GUIv1}
  ${CXBXR_SOURCE_COMMON}
 )
@@ -142,7 +142,7 @@ if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
   /Qpar \
   "
  )
- 
+
  # disable optimization for CxbxKrnl.cpp file
  set_source_files_properties(
   ${CXBXR_KRNL_CPP} PROPERTIES COMPILE_FLAGS "/Od /GL-"
@@ -150,7 +150,7 @@ if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
 endif()
 
 # Windows libraries
-set(WINS_LIB 
+set(WINS_LIB
  legacy_stdio_definitions
  d3d9
  d3dcompiler
@@ -170,6 +170,7 @@ set(WINS_LIB
  comctl32
  XINPUT9_1_0
  Iphlpapi
+ Dwmapi
 )
 
 target_link_libraries(cxbx

src/gui/WndMain.cpp

@@ -56,6 +56,8 @@
 #undef GetSystemMetrics // Force remove DirectX 8's multimon.h defined function (redirect to xGetSystemMetrics).
 #include <WinUser.h> // For GetSystemMetrics
 
+#include <dwmapi.h> // For DwmSetWindowAttribute
+
 #include <io.h>
 #include <shlobj.h>
 
@@ -323,6 +325,10 @@ LRESULT CALLBACK WndMain::WndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lP
 			ChangeWindowMessageFilterEx(hwnd, WM_COPYDATA, MSGFLT_ALLOW, nullptr);
 			ChangeWindowMessageFilterEx(hwnd, 0x0049, MSGFLT_ALLOW, nullptr);
 
+			// Remove rounded corners from the render window on Windows 11
+			const DWM_WINDOW_CORNER_PREFERENCE corner_preference = DWMWCP_DONOTROUND;
+			DwmSetWindowAttribute(hwnd, DWMWA_WINDOW_CORNER_PREFERENCE, &corner_preference, sizeof(corner_preference));
+
             m_bCreated = true;
         }
         break;