title: How to reference header files in visual studio 2017 project
body: <p>I have downloaded and tried to build The oxygine engine project with VS 2017 Community. The stringutils.cpp file from it gives me the following when I try to compile:</p>
  
  <pre><code>C1083: Cannot open include file: 'SDL_stdinc.h': No such file or directory
  </code></pre>
  
  <p>hovering the <code>#include</code> statement it says <code>cannot open source file 'SDL_stdinc.h'</code></p>
  
  <p>I checked </p>
  
  <blockquote>
    <p>Properties->C/C++->General->Additional Include Directories</p>
  </blockquote>
  
  <p>and it references the path the header files are in. I have even added another path representing the absolute path. I tried a different folder, a different download of the header files, all to no avail.</p>
  
  <p>What do I need to do to get this right?</p>
  
  <p>Is there any reason for a header to not work? (version mismatch or something)<br>
  Is a header not working if the corresponding dll or lib is missing?<br>
  If so, how do I know it is found by VS?</p>