.. include :: substitutions.txt

.. index:: !Map renderers

.. _map_renderers:

Map renderers
=============

This chapter describes the three map renderers available in |GC| and how to configure them.


.. index:: Google maps renderer
    pair: Map renderers; Google maps renderer

.. _google_maps:

|GM|
-------------

|GM| use Google Maps API v. 3 to display the map.

.. figure :: images/gc_fe_gmap.*

    The |GM| renderer.



.. note::

    Google's base layers are also available in the more flexible |OLM| and |OLWM| renderers. Please also note that there are some intrinsic limitations to the
    number of geometric features and the size of the KML file that can be shown with Google Maps (see: `<http://code.google.com/apis/kml/documentation/mapsSupport.html>`_ ).

.. warning::

    This map renderer works only when the website is deployed on a server which is accessible from the internet (it does not work on localhost) because Google must be able to retrieve KML data from your server in order to build the image tiles that are shown in the map.

.. warning::

    In some occasions, we observed Google servers failures when a layer contained over 500 points, this is a limitation of Google Maps API and cannot be fixed by |GC|. If you encounter similar problems, try switching to |OL| base maps.



.. index:: OpenLayers map renderer
    pair: Map renderers; OpenLayers map renderer


.. _openlayers_maps:

|OLM|
---------------

|OLM| uses plain |OL| renderer to display the map. It has more configuration options than |GM| and fine-grained styling features. Bing and Google layers are also available as base (background) layers for this maps.

.. figure :: images/gc_fe_olmap.*

    The |OLM| renderer.



.. index:: OLWidget map renderer
    pair: Map renderers; OLWidget map renderer



.. _olwidget_maps:

|OLWM|
---------------

|OLWM| uses a renderer built on top of |OL| renderer to display the map. It has more configuration options than |GM| and fine-grained styling features. Bing and Google layers are also available as base (background) layers for this maps.
In addition to all |OLM| options you can activate clustering for points, this renderer also uses a different template for balloons.

.. figure :: images/gc_fe_olwidgetmap.*

    The |OLWM| renderer.