Weiler–Atherton clipping algorithm: Difference between revisions

Revision as of 21:32, 23 July 2015

Revision as of 17:47, 6 August 2015

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- Candidate polygons need to be oriented clockwise.

- Candidate polygons should not be self intersecting (i.e. re-entrant).

- The algorithm can support holes (as counter-clockwise polygons wholly inside their parent polygon), but requires additional algorithms to decide which polygons are holes. Then, merging of polygons can be performed by a variant of the algorithm.

- The algorithm can support holes (as counter-clockwise polygons wholly inside their parent polygon), but requires additional algorithms to decide which polygons are holes. Then, merging of polygons can be performed by a variant of the algorithm.

== The Algorithm ==

Suppose, A is the clipping polygon/region/area, and, B is the candidate polygon/subject polygon/polygon to be clipped.