IlvRegionUpdater Class Reference

Utility class to update invalidated display regions. More...

#include <ilviews/base/region.h>

Public Member Functions
virtual IlBoolean	update (IlvRegion &region, const IlvRect &clip, const IlvTransformer *t=0) const =0
	Updates the refresh region. More...

Detailed Description

Utility class to update invalidated display regions.

Library: xviews or winviews or mviews (mutually exclusive)

This class lets you define the precise area that should be invalidated when modifications impact the display of a graphic holder. You typically create a subclass of IlvRegionUpdater that does the appropriate job depending on your context, and provide an instance of this class to IlvGraphicHolder::invalidateRegion(IlvRegionUpdater&,const IlvGraphic*).

Member Function Documentation

update()

virtual IlBoolean IlvRegionUpdater::update ( IlvRegion &  region, const IlvRect &  clip, const IlvTransformer *  t = 0  ) const

pure virtual

Updates the refresh region.

This member function is called when a graphic holder requests an update of its refresh area (what part of the views must be redrawn).

Parameters

region	The refresh region that must be updated by this member function, in the destination view coordinates system.
clip	The clipping rectangle of the display area. This parameter can be used to discard irrelevant region updates.
t	The transformer that must be taken into account to update the region.

Returns

IlTrue if a change is performed on region and IlFalse otherwise.