Perhaps replace and limit: congruency angle -> 2-fold rotational symmetry

[GoogleCodeExporter]

The idea is to introduce a flag: has2FoldSymmetry (boolean)

This would equal the option to specify a congruency angle of 180°.
Congruency angles of 90° and 270° could no longer be specified.

Rationale:

* A congruency angle 90° doesn't make much sense, and a congruency angle
  of 270° neither. By getting rid of these angles, things become
  simpler, and there is less to test.

* By having only a boolean flag, it is clear what is possible. There is
  no need to say something like: A congruency angle of 270° is not
  supported.

If renaming, don't forget to also update the documentation in:

* collisions.xar

* attachment.xar

Original issue reported on code.google.com by fe...@f76.eu on 13 Aug 2011 at 4:47

[GoogleCodeExporter]

Issue 81 has been merged into this issue.

Original comment by fe...@f76.eu on 14 Aug 2011 at 8:54

[GoogleCodeExporter]

Done.

Original comment by fe...@f76.eu on 14 Aug 2011 at 8:55

• Changed state: Fixed