Move points_in_polygon to Cython

[jwiggins]

Since I'm maneuvering to eliminate the agg extension from kiva, I need to do something with points_in_polygon. I believe the only reason it was part of that extension was to cut down on the number of extension modules being built. Now it lives in its own extension.

NOTE: I don't want to merge this until after 4.6.0 is released.

[codecov-io]

Current coverage is 52.08% (diff: 100%)

Merging #250 into master will increase coverage by 0.02%

@@             master       #250   diff @@
==========================================
  Files           126        127     +1   
  Lines         13176      13180     +4   
  Methods           0          0          
  Messages          0          0          
  Branches       1943       1941     -2   
==========================================
+ Hits           6859       6865     +6   
+ Misses         5872       5870     -2   
  Partials        445        445          

Powered by Codecov. Last update 5e4e7f1...b170a17

[corranwebster]

Generally a good idea, although I haven't tried this out.

[corranwebster]

This is a backwards-incompatible change which will require updating some stuff in Chaco (and at least one other internal project I know of).

Possibly this should be kept in kiva (although not in kiva.agg), rather than moved to enable? I'm in two minds.

[jwiggins]

I'm planning for kiva.agg to go away. If the import has to change, why not move it into enable at the same time? It doesn't seem drawing related, so that's my argument for not leaving it in kiva.

[corranwebster]

While this is currently used for hit detection and point selection by Chaco, this is the sort of routine that can be useful for higher-level drawing routine optimization (eg. avoiding drawing points which are obscured).

In other words, although it's not about drawing, it is about pure geometry, which seems a more Kiva-y thing than an Enable-y thing.

[jwiggins]

Agreed. I've moved the code back to kiva, but still outside of agg.

[jwiggins]

Thanks for reviewing!

[rkern]

@jwiggins Can you please expose it back in kiva.agg with a deprecation warning? This is part of the public API and used in Chaco, so now all of the Chaco PR Travis runs are failing. Migrating Chaco isn't hard, but then Chaco would be relying on an unreleased version of Enable. The deprecation period makes the coordination easier.

[jwiggins]

Sure thing