Matthew Webb and Emil Praun and Adam Finkelstein and Hugues Hoppe.
Fine Tone Control in Hardware Hatching.
In Proceedings of the 2nd International Symposium on Non-Photorealistic Animation and Rendering (NPAR 2002), pp. 53--58, 2002.

Bibtex:

@InProceedings{  webb:2002:FTCH,
  author = 	 "Matthew Webb and Emil Praun and Adam Finkelstein and
                  Hugues Hoppe",
  title = 	 "Fine Tone Control in Hardware Hatching",
  booktitle = 	 "Proceedings of the 2nd International Symposium on
                  Non-Photorealistic Animation and Rendering (NPAR
                  2002)",
  pages = 	 "53--58",
  year = 	 "2002",
}

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