..
.. Copyright (c) 2011 by Intevation GmbH, Germany <info@intevation.de>
.. 
.. This file is part of MXD2map.
..
.. This program is free software under the LGPL (>=v2.1)
.. Read the file LICENCE.txt coming with the software for details
.. or visit http://www.gnu.org/licenses/ if it does not exist.
..
.. MXD2map has been developed on behalf of the
.. Bundesamt fuer Seeschifffahrt und Hydrographie (BSH) in Hamburg
.. by Intevation GmbH.
..
.. Authors:
.. Raimund Renkert <raimund.renkert@intevation.de>
.. Bjoern Schilberg <bjoern.schilberg@intevation.de>
.. Stephan Holl <stephan.holl@intevation.de>


.. index:: restrictions, label, Raster, ArcSDE, SDE, workaround, picture-symols, windows, ArcEngine
.. _restriction-label:

------------
Restrictions
------------

Currently there are some restrictions in the usage of the converter. One
of the main restrictions is the fact that the converter currently only
runs on Windows. This is due to the fact that the needed ArcEngine did
never reliably work on Linux. This was tested with ArcEngine 10.0.

Supported datasources:

 * ArcSDE-passwords cannot be read since they are encrypted. The converter
   exports the string ``<PASSWORD>`` which needs to be replaced later on in the
   resulting mapfile.

 * Since MapServer cannot use a FileGeodatabase datasources (yet) the MXD2map
   does not support this datasource and will not transform the MXD-file at
   all. This may change in the near future.

 * Raster data is not supported by the converter yet, though ArcSDE
   Raster-support will be available in the near future.

Symbol support:

 * Line symbols with pattern cannot be combined with marker symbols. The
   converter reads all symbols and writes the corresponding styles to the
   resulting mapfile but the marker symbols are rendered without any gap.
   The resulting mapimage may not look as intended.

   .. hint::
     Workarround: For small marker symbols it is recommended to use a line symbol in
     combination with pattern (in ArcGIS called template) to create the
     symbology.
     The reason why marker symbols cannot be used in combination with a template
     is the difficulty to interpret the read attributes like marks and gaps and
     write the appropriate symbols with the appropiate gap to the mapfile.

 * The converter sets the width to 1 for line symbols that have a width
   smaller than 1. 

   .. tip::
     To avoid lines and line colors (specially outlines) to be handled by the
     converter, use integer numbers for line width only.

 * In ArcGIS maps default symbols can be defined as fallback within classifications. 
   Since MapServer does not support such fallback symbols or styles
   within classifications the converter does not read these default symbols.

 * In ArcGIS predefined symbols like bars or pie charts can be used to display
   values. The converter does not support these symbols yet.

Layer support:

 * Expressions for label are parsed by an internal parser in ArcGIS. The
   interpretation of this expressions is very limited though.
   Therefore label expressions may not contain any special functions or must fit
   the mapserver expression design pattern.