mapnik/mapnik — Issue #1072: remove locking around pj_transform for proj 4.7
Author: springmeyer
Created: 2012-02-10 01:07:35+00:00
State: open

Mutex locking was introduced around pj_transform to protect against the possibility of crashes a long time ago: http://comments.gmane.org/gmane.comp.gis.mapnik.devel/462

We now avoid this locking if proj 4.8 (current unreleased trunk) is detected, but I think we should do the same for 4.7.

My hunch is that the original problems were likely encountered due to pj_init (which proj 4.7 now protects against) and not pj_transform as I am unable to prompt crashes in unprotected pj_transform with proj 4.7 within TileMill, which uses multithreaded rendering.

This move is valuable because proj development is stalled and so linux systems relying on packages are stuck at 4.7 leading to cases for mapnik where multithreaded rendering is extremely slow.