mapnik/mapnik — pull request #1014 by tmcw (2012-01-09 18:16:25+00:00)
Title: Unbuffered extent

This patch gives access to an unbuffered extent through the datasource API. Its backwards-compatible with all existing datasources and has been stable in my testing, but could use some deeper insight into how to handle this use case.

This was necessary because of the work in [jit_datasource](https://github.com/mapbox/jit_datasource), which [uses the unbuffered box](https://github.com/mapbox/jit_datasource/blob/master/jit_datasource.cpp#L196) in order to determine the original requested tile dimensions and location.