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= Developer's Information =

This page is targeted at developers wishing to delve deeper into Proj4js internals.

== Building custom versions of Proj4js ==

The proj4js/build directory contains some scripts that can be use to build a single file (buildUncompressed.py) and compressed (build.py) versions of the Proj4js library.  The build process is controlled by the file library.cfg.  To build the library:
{{{
cd proj4js/build
./build.py
}}}

By default, all projection class code is included in the resulting file.  If only a subset of projections are required, then the library.cfg file can be edited to include or exclude the pieces required.  For example, if your application will only ever use EPSG:27563 and the LCC projection, library.cfg can be edited to be:
{{{
[first]
proj4js.js

[last]

[include]
projCode/lcc.js
defs/EPSG27563.js

[exclude]
defs/*
}}}

Similarly, OLprototype.cfg is the build configuration file used to create the OLprototype.js file with the OpenLayers build script.  In general, there will be no need to modify this file.

== The test suite ==

== Adding projection class code ==

== Datum Transforms ==