title: For a point in a concave polygon, what is the closest point outside the polygon?
body: <p>I have a point located inside a concave polygon and I want to find the closest point that is <em>just</em> outside the polygon. I implemented the answer in: <a href="https://stackoverflow.com/questions/6176227/for-a-point-in-an-irregular-polygon-what-is-the-most-efficient-way-to-select-th">For a point in an irregular polygon, what is the most efficient way to select the edge closest to the point?</a> but that finds the closest point on a polygon edge, not outside the polygon.</p>
  
  <p>I tried just extending the line from the point inside the polygon to the point on the edge, but there are instances where that wont work.</p>
  
  <p>Any suggestions?</p>
  
  <p><strong>EDIT:</strong> To make it more clear, I have a point inside a concave or convex polygon, and I want to find a point outside the polygon, as close as possible to the point inside. So in below illustration, I want to find the red point. It doesn't have to be perfectly minimized in distance, just needs to be outside and not too far from the original point. Maybe by a fixed amount?</p>
  
  <p><a href="https://i.stack.imgur.com/ZYrLH.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ZYrLH.png" alt="enter image description here"></a></p>