title: Low level mouse hook - mouse button click vs hold
body: <p>I'm using C++ and DirectD3D9 to draw a menu.
  I wish to navigate the menu with the mouse.
  I can get the mouse position, however, checking if the left button is clicked is proving tricky.
  I am able to check if it is being held down, but not clicked.</p>
  
  <pre><code>bool LBUTTONDOWN = false;
  LRESULT CALLBACK LowLevelMouseProc(int nCode, WPARAM wParam, LPARAM lParam) {
      if (nCode == HC_ACTION &amp;&amp; (wParam == WM_LBUTTONUP || wParam == WM_LBUTTONDOWN)) {
          LBUTTONDOWN = wParam == WM_LBUTTONDOWN;
      }
      return CallNextHookEx(0, nCode, wParam, lParam);
  }
  </code></pre>
  
  <p>How can I add a check to see if I clicked the left button?</p>