virtual void readXml(const QDomElement &elem, const QgsReadWriteContext &context=QgsReadWriteContext())=0
Reads configuration from a DOM element previously written using writeXml().
virtual QDomElement writeXml(QDomDocument &doc, const QgsReadWriteContext &context=QgsReadWriteContext()) const =0
Writes the light source's configuration to a new DOM element and returns it.
The class is used as a container of context for various read/write operations on other objects.