Fix XP build

nel/src/3d/driver/direct3d/driver_direct3d.cpp

@@ -1265,9 +1265,11 @@ static LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM l
 		return 0;
 	}
 
+#ifdef WM_UNICHAR
 	// https://docs.microsoft.com/en-us/windows/win32/inputdev/wm-unichar
 	if (message == WM_UNICHAR)
 		return (wParam == UNICODE_NOCHAR);
+#endif
 
 	return DefWindowProcW(hWnd, message, wParam, lParam);
 }

nel/src/3d/driver/opengl/driver_opengl_window.cpp

@@ -183,9 +183,11 @@ static LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM l
 		return 0;
 	}
 
+#ifdef WM_UNICHAR
 	// https://docs.microsoft.com/en-us/windows/win32/inputdev/wm-unichar
 	if (message == WM_UNICHAR)
 		return (wParam == UNICODE_NOCHAR);
+#endif
 
 	return trapMessage ? 0 : DefWindowProcW(hWnd, message, wParam, lParam);
 }

nel/src/misc/inter_window_msg_queue.cpp

@@ -459,9 +459,11 @@ namespace NLMISC
 		{
 			return handleWMCopyData(hwnd, (COPYDATASTRUCT *) lParam);
 		}
+#ifdef WM_UNICHAR
 		// https://docs.microsoft.com/en-us/windows/win32/inputdev/wm-unichar
 		if (uMsg == WM_UNICHAR)
 			return (wParam == UNICODE_NOCHAR);
+#endif
 		return DefWindowProc(hwnd, uMsg, wParam, lParam);
 	}
 

nel/src/misc/win_event_emitter.cpp

@@ -162,6 +162,7 @@ bool CWinEventEmitter::processMessage (HWND hWnd, uint32 msg, WPARAM wParam, LPA
 				server->postEvent (new CEventKeyUp ((NLMISC::TKey)wParam, getKeyButton(_AltButton, _ShiftButton, _CtrlButton), this));
 		}
 		break;
+#ifdef WM_UNICHAR
 	case WM_UNICHAR:
 		if (wParam != UNICODE_NOCHAR && _KeyboardEventsEnabled)
 		{
@@ -170,11 +171,15 @@ bool CWinEventEmitter::processMessage (HWND hWnd, uint32 msg, WPARAM wParam, LPA
 			server->postEvent (new CEventChar ((u32char)wParam, getKeyButton(_AltButton, _ShiftButton, _CtrlButton), this));
 		}
 		break;
+#endif
 	case WM_CHAR:
 		if (_KeyboardEventsEnabled)
 		{
 			//if (wParam < KeyCount)
 			//nlinfo("WM_CHAR with %u", wParam);
+#ifndef WM_UNICHAR
+			// FIXME: Combine UTF-16 pairs
+#endif
 			server->postEvent (new CEventChar ((ucchar)wParam, getKeyButton(_AltButton, _ShiftButton, _CtrlButton), this));
 		}
 		break;