title: What does the "zoom factor" mean in OLECMDID_OPTICAL_ZOOM?
body: <p>I am using ExecWB() to zoom in/out my WebBrowser control like this:</p>
  
  <pre><code>m_lpBrowser-&gt;ExecWB(OLECMDID_OPTICAL_ZOOM, OLECMDEXECOPT_DONTPROMPTUSER, &amp;(CComVariant)zoomFactor, NULL);
  </code></pre>
  
  <p>This works just fine when my OS dpi is 100% (96 dpi). However, under OS dpi 150% (144 dpi), setting zoom factor as 100 makes the web page in the browser look much smaller.(I was expecting to get exactly the same layout as the one under OS dpi 100%)</p>
  
  <p>Then I found an old <a href="https://tracker.moodle.org/secure/attachment/13577/Zoom.pdf" rel="nofollow">IE8 document</a>.</p>
  
  <p>In this document, <code>OLECMDID_OPTICAL_ZOOM</code> is said to be setting the <code>ZOOM FACTOR</code> of the browser
  ( <code>ZOOM FACTOR = System DPI / Layout DPI</code>)</p>
  
  <p>But I just can't figure out the meaning of <code>Layout DPI</code>. Is this the root cause that I get smaller web pages?</p>