title: WM_PAINT and DX12
body: <p><strong>Hi!</strong></p>
  <p>Could someone anwser my question, please?
  My program has one thread for the window's message loop and another for D3D12 rendering.
  Everything is fine, but the question is what window proc. should do with WM_PAINT?
  Currently the app has such fragment of code:</p>
  <pre><code>case WM_PAINT:
      return 0;
  </code></pre>
  <p>Is there any better/more efficient way, or that is OK?</p>