Recent work has shown that sparse lines defined on 3D shapes, including occluding contours and suggestive contours, are effective at conveying shape. We introduce two new families of lines called suggestive highlights and principal highlights, based on definitions related to suggestive contours and geometric creases. We show that when these are drawn in white on a gray background they are naturally interpreted as highlight lines, and complement contours and suggestive contours. We provide object-space definitions and algorithms for extracting these lines, explore several stylization possibilities, and compare the lines to ridges and valleys of intensity in diffuse-shaded images.

@inproceedings{DeCarlo:2007:HLF,
   author = "Doug DeCarlo and Szymon Rusinkiewicz",
   title = "Highlight Lines for Conveying Shape",
   booktitle = "International Symposium on Non-Photorealistic Animation and Rendering
      (NPAR)",
   year = "2007",
   month = aug
}