Eliminate double definitions.
Eliminate unneeded comments.
In common.scad redefine num_defined(), all_defined() and get_radius().
In geometry.scad:
- change name _dist to _dist2line
- simplify _point_above_below_segment() and triangle_area()
- change some arg names for uniformity (path>>poly)
- change point_in_polygon() to accept the Even-odd rule as alternative
- and other minor edits
Update tests_geometry to the new funcionalities.
Besides param validation and some formating, changes:
A. add new functions:
1. _valid_line()
2. _valid_plane()
3. line_from_points()
4. projection_on_plane()
5. points_on_plane()
B. rename/redefine/remove functions:
1. points_are_coplanar() >> coplanar()
2. collinear() works with list of points as well as coplanar()
3. find_noncollinear_points >> noncollinear_triple
4. collinear_indexed() removed
5. polygon_is_convex() >> is_convex_polygon()
C. recode/optimize the codes of the functions:
1. point_on_segment2d()
2. point_left_of_line2d()
3. distance_from_line()
4. line_closest_point()
5. plane_from_polygon()
6. _general_plane_line_intersection()
7. polygon_line_intersection()
8. find_circle_2tangents()
9. find_circle_3points()
10. polygon_area()
11. is_convex_polygon()
12. reindex_polygon()
13. centroid()
14. polygon_is_clockwise()
15. clockwise_polygon()
16. ccw_polygon()
The function name changes were updated in:
test_geometry.scad
hull.scad
rounding.scad
vnf.scad
Regression tests for the new external functions were included in test_geometry.scad.
Unsolved questions:
1. why sorting the indices in plane_from_points and polygon_line_intersection?
2. aren't redundant plane_from_polygon() and plane_from_points()?
needs a name change. Adds apply(), apply_list() and
affine_frame_map() to affine.scad. Adds derivative calcluation to
math.scad. Adds path_tangent, path_normal, path_curvature and
path_torsion functions. Adds path_length_fraction().
Fixed bug in reindex_polygon where it randomly reverses a 3d path (due
to clockwise check that is bogus in 3d) and put a check in
polygon_is_clockwise to trap this case.
