參考文獻

[1] Meijster, Arnold, Jos BTM Roerdink, and Wim H Hesselink. A General Algorithm for Computing Distance Transforms in Linear Time. In Mathematical Morphology and Its Applications to Image and Signal Processing. Springer. 331-40, 2002.

[2] Quilez, Inigo. Modeling with Distance Functions, 2008. http://iquilezles.org/www/articles/distfunctions/distfunctions.htm.