CGAL way for storing are retrieving geometric information a for full cell in the triangulation -

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i'm planning on using cgal triangulation , delaunay triangulation classes backbone geometric structure robot motion planning algorithms. main difficulty have encountered far in assigning geometric data full cells in abstract complex. example, in order find shortest path through full cell need compute set of normal vectors facets. purpose, use expensive pseudo inverse procedure. since, these computations have done several times in each full cell, prefer store data once computed, , retrieve during successive computations. in addition, store collision data each full cell instead of recomputing on again after refining given triangulation.

browsing answers here , trying understand structure of cgal, reached understanding on subject:

  1. it bad idea rewrite geometric kernel this...
  2. i've seen examples of using vertex base class info in points augmented indices here. although using triangulation_cell_base_with_info seems easy workaround, consider inelegant hack because requires me implement wrapper class keeping additional data , pass class planning algorithm.
  3. i can derive cell class triangulation_ds_cell_base. looks acceptable way things, cannot find example of code me started. need not class derivation, example code on how access cell data in various scenarios: through iterator, vertex adjacency, , on.

so, here 2 questions:

  1. what cgal way store , retrieve additional geometric data per cell?
  2. is there example of code doing that?

edit: forgot mention need use dd triangulation introduced in cgal 4.6


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