internal/glfw: bug fix: disabling cursor doesn't work well on remote desktop

This change applies the bug fix at glfw/glfw#1276

Updates #2961

internal/glfw/api_windows.go

@@ -100,6 +100,7 @@ const (
 	_MAPVK_VSC_TO_VK                                           = 1
 	_MONITOR_DEFAULTTONEAREST                                  = 0x00000002
 	_MOUSE_MOVE_ABSOLUTE                                       = 0x01
+	_MOUSE_VIRTUAL_DESKTOP                                     = 0x02
 	_MSGFLT_ALLOW                                              = 1
 	_OCR_CROSS                                                 = 32515
 	_OCR_HAND                                                  = 32649
@@ -141,11 +142,18 @@ const (
 	_SIZE_MAXIMIZED                                            = 2
 	_SIZE_MINIMIZED                                            = 1
 	_SIZE_RESTORED                                             = 0
+	_SM_CXCURSOR                                               = 13
 	_SM_CXICON                                                 = 11
 	_SM_CXSMICON                                               = 49
 	_SM_CYCAPTION                                              = 4
+	_SM_CYCURSOR                                               = 14
 	_SM_CYICON                                                 = 12
+	_SM_CXSCREEN                                               = 0
+	_SM_CYSCREEN                                               = 1
 	_SM_CYSMICON                                               = 50
+	_SM_CXVIRTUALSCREEN                                        = 78
+	_SM_CYVIRTUALSCREEN                                        = 79
+	_SM_REMOTESESSION                                          = 0x1000
 	_SPI_GETFOREGROUNDLOCKTIMEOUT                              = 0x2000
 	_SPI_GETMOUSETRAILS                                        = 94
 	_SPI_SETFOREGROUNDLOCKTIMEOUT                              = 0x2001
@@ -755,9 +763,11 @@ var (
 	procChangeWindowMessageFilterEx   = user32.NewProc("ChangeWindowMessageFilterEx")
 	procClientToScreen                = user32.NewProc("ClientToScreen")
 	procClipCursor                    = user32.NewProc("ClipCursor")
+	procCreateCursor                  = user32.NewProc("CreateCursor")
 	procCreateIconIndirect            = user32.NewProc("CreateIconIndirect")
 	procCreateWindowExW               = user32.NewProc("CreateWindowExW")
 	procDefWindowProcW                = user32.NewProc("DefWindowProcW")
+	procDestroyCursor                 = user32.NewProc("DestroyCursor")
 	procDestroyIcon                   = user32.NewProc("DestroyIcon")
 	procDestroyWindow                 = user32.NewProc("DestroyWindow")
 	procDispatchMessageW              = user32.NewProc("DispatchMessageW")
@@ -915,6 +925,26 @@ func _ClipCursor(lpRect *_RECT) error {
 	return nil
 }
 
+func _CreateCursor(hInst _HINSTANCE, xHotSpot int32, yHotSpot int32, nWidth int32, nHeight int32, pvANDPlane, pvXORPlane []byte) (_HCURSOR, error) {
+	var andPlane *byte
+	if len(pvANDPlane) > 0 {
+		andPlane = &pvANDPlane[0]
+	}
+	var xorPlane *byte
+	if len(pvXORPlane) > 0 {
+		xorPlane = &pvXORPlane[0]
+	}
+
+	r, _, e := procCreateCursor.Call(uintptr(hInst), uintptr(xHotSpot), uintptr(yHotSpot), uintptr(nWidth), uintptr(nHeight), uintptr(unsafe.Pointer(andPlane)), uintptr(unsafe.Pointer(xorPlane)))
+	runtime.KeepAlive(pvANDPlane)
+	runtime.KeepAlive(pvXORPlane)
+
+	if _HCURSOR(r) == 0 && !errors.Is(e, windows.ERROR_SUCCESS) {
+		return 0, fmt.Errorf("glfw: CreateCursor failed: %w", e)
+	}
+	return _HCURSOR(r), nil
+}
+
 func _CreateBitmap(nWidth int32, nHeight int32, nPlanes uint32, nBitCount uint32, lpBits unsafe.Pointer) (_HBITMAP, error) {
 	r, _, e := procCreateBitmap.Call(uintptr(nWidth), uintptr(nHeight), uintptr(nPlanes), uintptr(nBitCount), uintptr(lpBits))
 	if _HBITMAP(r) == 0 {
@@ -986,6 +1016,14 @@ func _DefWindowProcW(hWnd windows.HWND, uMsg uint32, wParam _WPARAM, lParam _LPA
 	return _LRESULT(r)
 }
 
+func _DestroyCursor(hCursor _HCURSOR) error {
+	r, _, e := procDestroyCursor.Call(uintptr(hCursor))
+	if int32(r) == 0 && !errors.Is(e, windows.ERROR_SUCCESS) {
+		return fmt.Errorf("glfw: DestroyCursor failed: %w", e)
+	}
+	return nil
+}
+
 func _DestroyIcon(hIcon _HICON) error {
 	r, _, e := procDestroyIcon.Call(uintptr(hIcon))
 	if int32(r) == 0 && !errors.Is(e, windows.ERROR_SUCCESS) {

internal/glfw/win32_init_windows.go

@@ -239,6 +239,55 @@ func createHelperWindow() error {
 	return nil
 }
 
+func createBlankCursor() error {
+	// HACK: Create a transparent cursor as using the NULL cursor breaks
+	//       using SetCursorPos when connected over RDP
+	cursorWidth, err := _GetSystemMetrics(_SM_CXCURSOR)
+	if err != nil {
+		return err
+	}
+	cursorHeight, err := _GetSystemMetrics(_SM_CYCURSOR)
+	if err != nil {
+		return err
+	}
+	andMask := make([]byte, cursorWidth*cursorHeight/8)
+	for i := range andMask {
+		andMask[i] = 0xff
+	}
+	xorMask := make([]byte, cursorWidth*cursorHeight/8)
+
+	// Cursor creation might fail, but that's fine as we get NULL in that case,
+	// which serves as an acceptable fallback blank cursor (other than on RDP)
+	c, _ := _CreateCursor(0, 0, 0, cursorWidth, cursorHeight, andMask, xorMask)
+	_glfw.platformWindow.blankCursor = c
+
+	return nil
+}
+
+func initRemoteSession() error {
+	if microsoftgdk.IsXbox() {
+		return nil
+	}
+
+	// Check if the current progress was started with Remote Desktop.
+	r, err := _GetSystemMetrics(_SM_REMOTESESSION)
+	if err != nil {
+		return err
+	}
+	_glfw.platformWindow.isRemoteSession = r > 0
+
+	// With Remote desktop, we need to create a blank cursor because of the cursor is Set to nil
+	// if cannot be moved to center in capture mode. If not Remote Desktop platformWindow.blankCursor stays nil
+	// and will perform has before (normal).
+	if _glfw.platformWindow.isRemoteSession {
+		if err := createBlankCursor(); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
 func platformInit() error {
 	// Changing the foreground lock timeout was removed from the original code.
 	// See https://github.com/glfw/glfw/commit/58b48a3a00d9c2a5ca10cc23069a71d8773cc7a4
@@ -293,6 +342,10 @@ func platformInit() error {
 			return err
 		}
 	} else {
+		// Some hacks are needed to support Remote Desktop...
+		if err := initRemoteSession(); err != nil {
+			return err
+		}
 		if err := pollMonitorsWin32(); err != nil {
 			return err
 		}
@@ -301,6 +354,12 @@ func platformInit() error {
 }
 
 func platformTerminate() error {
+	if _glfw.platformWindow.blankCursor != 0 {
+		if err := _DestroyCursor(_glfw.platformWindow.blankCursor); err != nil {
+			return err
+		}
+	}
+
 	if _glfw.platformWindow.deviceNotificationHandle != 0 {
 		if err := _UnregisterDeviceNotification(_glfw.platformWindow.deviceNotificationHandle); err != nil {
 			return err

internal/glfw/win32_platform_windows.go

@@ -66,14 +66,18 @@ type platformLibraryWindowState struct {
 	scancodes                [KeyLast + 1]int
 	keynames                 [KeyLast + 1]string
 
-	// Where to place the cursor when re-enabled
+	// restoreCursorPosX and restoreCursorPosY indicates where to place the cursor when re-enabled
 	restoreCursorPosX float64
 	restoreCursorPosY float64
 
-	// The window whose disabled cursor mode is active
+	// disabledCursorWindow is the window whose disabled cursor mode is active
 	disabledCursorWindow *Window
-	// The window the cursor is captured in
+	// capturedCursorWindow is the window the cursor is captured in
 	capturedCursorWindow *Window
 	rawInput             []byte
 	mouseTrailSize       uint32
+	// isRemoteSession indicates if the process was started behind Remote Destop
+	isRemoteSession bool
+	// blankCursor is an invisible cursor, needed for special cases (see WM_INPUT handler)
+	blankCursor _HCURSOR
 }

internal/glfw/win32_window_windows.go

@@ -167,7 +167,10 @@ func (w *Window) updateCursorImage() error {
 			_SetCursor(cursor)
 		}
 	} else {
-		_SetCursor(0)
+		// Connected via Remote Desktop, nil cursor will present SetCursorPos the move the cursor.
+		// using a blank cursor fix that.
+		// When not via Remote Desktop, platformWindow.blankCursor should be nil.
+		_SetCursor(_glfw.platformWindow.blankCursor)
 	}
 	return nil
 }
@@ -907,8 +910,46 @@ func windowProc(hWnd windows.HWND, uMsg uint32, wParam _WPARAM, lParam _LPARAM)
 		var dx, dy int
 		data := (*_RAWINPUT)(unsafe.Pointer(&_glfw.platformWindow.rawInput[0]))
 		if data.mouse.usFlags&_MOUSE_MOVE_ABSOLUTE != 0 {
-			dx = int(data.mouse.lLastX) - window.platform.lastCursorPosX
+			if _glfw.platformWindow.isRemoteSession {
-			dy = int(data.mouse.lLastY) - window.platform.lastCursorPosY
+				// Remote Desktop Mode
+				// As per https://github.com/Microsoft/DirectXTK/commit/ef56b63f3739381e451f7a5a5bd2c9779d2a7555
+				// MOUSE_MOVE_ABSOLUTE is a range from 0 through 65535, based on the screen size.
+				// Apparently, absolute mode only occurs over RDP though.
+				var smx int32 = _SM_CXSCREEN
+				var smy int32 = _SM_CYSCREEN
+				if data.mouse.usFlags&_MOUSE_VIRTUAL_DESKTOP != 0 {
+					smx = _SM_CXVIRTUALSCREEN
+					smy = _SM_CYVIRTUALSCREEN
+				}
+
+				width, err := _GetSystemMetrics(smx)
+				if err != nil {
+					_glfw.errors = append(_glfw.errors, err)
+					return 0
+				}
+				height, err := _GetSystemMetrics(smy)
+				if err != nil {
+					_glfw.errors = append(_glfw.errors, err)
+					return 0
+				}
+
+				pos := _POINT{
+					x: int32(float64(data.mouse.lLastX) / 65535.0 * float64(width)),
+					y: int32(float64(data.mouse.lLastY) / 65535.0 * float64(height)),
+				}
+				if err := _ScreenToClient(window.platform.handle, &pos); err != nil {
+					_glfw.errors = append(_glfw.errors, err)
+					return 0
+				}
+
+				dx = int(pos.x) - window.platform.lastCursorPosX
+				dy = int(pos.y) - window.platform.lastCursorPosY
+			} else {
+				// Normal mode
+				// We should have the right absolute coords in data.mouse
+				dx = int(data.mouse.lLastX) - window.platform.lastCursorPosX
+				dy = int(data.mouse.lLastY) - window.platform.lastCursorPosY
+			}
 		} else {
 			dx = int(data.mouse.lLastX)
 			dy = int(data.mouse.lLastY)
@@ -2159,6 +2200,7 @@ func platformPollEvents() error {
 
 		// NOTE: Re-center the cursor only if it has moved since the last call,
 		//       to avoid breaking glfwWaitEvents with WM_MOUSEMOVE
+		// The re-center is required in order to prevent the mouse cursor stopping at the edges of the screen.
 		if window.platform.lastCursorPosX != width/2 || window.platform.lastCursorPosY != height/2 {
 			if err := window.platformSetCursorPos(float64(width/2), float64(height/2)); err != nil {
 				return err