Lock the mouse cursor to the rendering window when the user presses F3 key

src/core/hle/D3D8/Direct3D9/Direct3D9.cpp

@@ -675,6 +675,18 @@ void DrawUEM(HWND hWnd)
 	EndPaint(hWnd, &ps);
 }
 
+void CxbxClipCursor(HWND hWnd)
+{
+	RECT wnd_rect;
+	GetWindowRect(hWnd, &wnd_rect);
+	ClipCursor(&wnd_rect);
+}
+
+void CxbxReleaseCursor()
+{
+	ClipCursor(nullptr);
+}
+
 inline DWORD GetXboxCommonResourceType(const xbox::DWORD XboxResource_Common)
 {
 	DWORD dwCommonType = XboxResource_Common & X_D3DCOMMON_TYPE_MASK;
@@ -1928,6 +1940,17 @@ static LRESULT WINAPI EmuMsgProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lPar
             {
                 VertexBufferConverter.PrintStats();
             }
+            else if (wParam == VK_F3)
+            {
+                g_bClipCursor = !g_bClipCursor;
+
+                if (g_bClipCursor) {
+                    CxbxClipCursor(hWnd);
+                }
+                else {
+                    CxbxReleaseCursor();
+                }
+            }
             else if (wParam == VK_F6)
             {
                 // For some unknown reason, F6 isn't handled in WndMain::WndProc
@@ -1990,6 +2013,26 @@ static LRESULT WINAPI EmuMsgProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lPar
                 }
                 break;
             }
+
+            if (g_bClipCursor) {
+                CxbxClipCursor(hWnd);
+            }
+        }
+        break;
+
+        case WM_MOVE:
+        {
+            if (g_bClipCursor) {
+                CxbxClipCursor(hWnd);
+            }
+        }
+        break;
+
+        case WM_MOUSEMOVE:
+        {
+            if (g_bClipCursor) {
+                CxbxClipCursor(hWnd);
+            }
         }
         break;
 

src/core/kernel/init/CxbxKrnl.cpp

@@ -112,7 +112,7 @@ size_t g_SystemMaxMemory = 0;
 
 HANDLE g_CurrentProcessHandle = 0; // Set in CxbxKrnlMain
 bool g_bIsWine = false;
-
+bool g_bClipCursor = false;
 bool g_CxbxPrintUEM = false;
 ULONG g_CxbxFatalErrorCode = FATAL_ERROR_NONE;
 

src/core/kernel/init/CxbxKrnl.h

@@ -200,7 +200,7 @@ bool CxbxIsElevated();
 extern uint32_t CxbxKrnl_KernelThunkTable[379];
 
 extern bool g_bIsWine;
-
+extern bool g_bClipCursor;
 extern bool g_CxbxPrintUEM;
 extern ULONG g_CxbxFatalErrorCode;