This is a big interest of mine because of my work on the Makelangelo Software. The software converts a photo to lines by starting with Stippling, where dots are put on the picture in a meaningful way. Everything that flows from there starts with good stippling. Wang Tiles are the current best method, prove me wrong.
I don’t have a way to make wang tiles as described in this video yet. If I had a set I’m confident I could do the rest in short order.