Shapely 1.0.4

One bug fix and a simple GEOS geometry cache to improve performance when wrapping coordinate data stored outside of Shapely.

In comments on a post about Javascript geometries, Paul Ramsey and Martin Davis wondered about a pure Python version of JTS. It might be an interesting project, and maybe you could coax reasonable performance out of it with psyco or Cython, but it wouldn't perform as well as something based on C (for C Python) or Java (for Jython) or C# (for IronPython). Consider Ian Bicking's HTML parsing benchmarks: lxml, based on libxml2, is far faster than anything else. The need to calculate spatial operations in C rather than Python is greater yet.

If Google would provide some basic spatial indexing (for App Engine), you could try to go the rest of the distance with the help of an external web geoprocessing service. You might not need a PyTS after all.


Re: Shapely 1.0.4

Author: Martin Davis

Sean, you must have been reading my mind. I was going to email you and ask if you thought there was any need for a pure Python port of JTS. I guess I'm not surprised to hear that a PyTS wouldn't have the performance of JTS or GEOS. On the other hand, there are lots of times where what is needed is functionality, and performance is a secondary concern. Perhaps the input data is small or well-bounded, or there aren't tight requirements on response time. (Human-facing spatial apps often fit this profile). So I'm not convinced that there wouldn't be an audience for PyTS. Any interest in exploring what it would take and how it might happen?

Re: Shapely 1.0.4

Author: Sean

Send me that email, Martin.