I know that some of you use Adobe Illustrator. Do you know if there is a way to easily find and outline a collection of lines that make up an illustration?
In this example, I printed my suppress hidden line 3D model to PDF (essentially a 2D illustration now) and opened in Illustrator. I could find no easy method to select and outline the outer perimeter. What I did to get the outer perimeter was to render my 3d model without lights and materials so it rendered as a black silhouette. I open the rendered image in Illustrator and used the trace functions to create a vector outline. I then just stacked the results an assigned a thicker stroke to the trace.