Scarygami/journey-to-the-moon — pull request #1 by timwintle (2014-01-08 11:14:16+00:00)
Title: Three optimisations for city lookup.

Changes:
* Coercing the latitude and longitude to floats for performance during lookup
* Batching up to 100 city updates in a single javascript interpreter entry
* Adding quick Manhattan distance check which avoids using trig functions

The main bottleneck is the method of iterating over cities with setTimeout. The profiler suggests about 50% of time is spent updating the UI and only 50% is spent analysing the data now.