This page briefly describes and summaries analogies to OpenOffice.org's chart component and where relevant code can be found, may it be for compatability or for inspiration.
Where to find it
Chart support in OpenOffice.org is located in its 'core' component: 
The sources for importing/exporting chart contents from/to ODF is located in xmloff/source/chart/ .
For import, SchXMLImport.cxx is the central file, SchXMLExport.cxx for export.