============================
About the Geogebra Filter :
============================

The Geogebra Filter makes use of XSLT ( Extensible Stylesheet Language Transformations ).
Qt's XmlPatterns Module is used for providing support for XSLT. Using XSLT we
first convert the XML representation of the Geogebra files into a more suitable intermediate
representation from which constructing the ObjectCalcers ( and thus the objectHolders )
is easier and homogenous for most object-types. We use the callback interface provided
by the QAbstractXmlReceiver class to read the transformed XML and construct the objects
present in the document.


Important Classes :
===================

There are two important classes involved :

1) GeogebraSection Class -
   This class stores the Objects present in the document (either
   a worksheet or a tool file ). The input-Objects and the
   output-Objects are kept track of by using objects of this class in the GeogebraTransformer
   class.

2) GeogebraTransformer Class -
   This class transforms the XML representation of the
   Geogebra files into a more suitable intermediate XML
   representation from which readingand allocating corresponding objectHolders is easier and
   homogenous. The two filters - worksheet-filter and tool-filter make use of  objects of this class.


File-Types Supported and Usage :
================================

The Geogebra Filter supports both types of Geogebra-files - 1) Geogebra WorkSheets
                                                            2) Geogebra Tools
WorkSheets files can be opened from the open-file Dialog ( just like .kig files of Kig ).
Tool files can be opened from the types Dialog. The behaviour in case of tool files
is exactly similar to that of Kig's macros ( .kigt files ).
