if (isMenuActive != lastIsMenuActive)
{
if (isMenuActive)
{
/* Remove TRANSPARENT and NOACTIVATE. */
LONG ex = GetWindowLong(hwnd, GWL_EXSTYLE);
ex &= ~WS_EX_TRANSPARENT;
ex &= ~WS_EX_NOACTIVATE;
ex |= (WS_EX_TOPMOST | WS_EX_LAYERED | WS_EX_TOOLWINDOW);
SetWindowLong(hwnd, GWL_EXSTYLE, ex);
SetWindowPos
(
hwnd, nullptr, 0, 0, 0, 0,
SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER | SWP_FRAMECHANGED
);

/* Activate the overlay so the game stops receiving input. */
DWORD gameTid = GetWindowThreadProcessId(hTargetWindow, nullptr);
DWORD myTid = GetCurrentThreadId();
AttachThreadInput(myTid, gameTid, TRUE);
SetForegroundWindow(hwnd);
SetActiveWindow(hwnd);
SetFocus(hwnd);
AttachThreadInput(myTid, gameTid, FALSE);

/* Capture the mouse (all WM_MOUSE messages go to us). */
if (GetCapture() != hwnd)
SetCapture(hwnd);

/* If the game hides the cursor, draw the ImGui cursor. */
ImGui::GetIO().MouseDrawCursor = true;
}
else
{
/* Restore click-through behavior for the overlay. */
LONG ex = GetWindowLong(hwnd, GWL_EXSTYLE);
ex |= WS_EX_TRANSPARENT;
ex &= ~WS_EX_NOACTIVATE; // keep without NOACTIVATE so clicking can activate
ex |= (WS_EX_TOPMOST | WS_EX_LAYERED | WS_EX_TOOLWINDOW);
SetWindowLong(hwnd, GWL_EXSTYLE, ex);
SetWindowPos
(
hwnd, nullptr, 0, 0, 0, 0,
SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER | SWP_FRAMECHANGED
);

if (GetCapture() == hwnd)
ReleaseCapture();

ImGui::GetIO().MouseDrawCursor = false;

/* Return focus to the game. */
if (IsWindow(hTargetWindow))
SetForegroundWindow(hTargetWindow);
}