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RRegion Class Reference

class RRegion : public TRegion

Expandable region.

This class provides for the construction and destruction of a TRegion , including a granularity for expanding the region. A region;s granularity represents the number of memory slots allocated when the object is created, and the number of new memory slots allocated each time an RRegion is expanded beyond the number of free slots. The default granularity is five.

Inherits from

RRegion
- TRegion

Public Member Functions
	RRegion ()
	RRegion ( TInt )
	RRegion (const RRegion &)
	RRegion (const TRect &, TInt )
	RRegion ( TInt , TRect *, TInt )
TInt	CheckSpare ()
IMPORT_C void	Close ()
IMPORT_C void	Destroy ()

Protected Member Functions
	RRegion ( TInt , TInt )

Inherited Functions
	TRegion::AddRect(const TRect &)
	TRegion::AppendRect(const TRect &)
	TRegion::AppendRegion(TRegion &)
	TRegion::BoundingRect()const
	TRegion::CheckError()const
	TRegion::Clear()
	TRegion::ClipRect(const TRect &)
	TRegion::Contains(const TPoint &)const
	TRegion::Copy(const TRegion &)
	TRegion::Count()const
	TRegion::DeleteRect(TRect *)
	TRegion::ExpandRegion(TInt)
	TRegion::ForceError()
	TRegion::Intersect(const TRegion &)
	TRegion::Intersection(const TRegion &,const TRegion &)
	TRegion::Intersects(const TRect &)const
	TRegion::IsContainedBy(const TRect &)const
	TRegion::IsEmpty()const
	TRegion::MergeRect(const TRect &,TBool)
	TRegion::Offset(TInt,TInt)
	TRegion::Offset(const TPoint &)
	TRegion::RectangleList()const
	TRegion::RectangleListW()
	TRegion::SetListSize(TInt)
	TRegion::ShrinkRegion()
	TRegion::Sort()
	TRegion::Sort(const TPoint &)
	TRegion::SubRect(const TRect &,TRegion *)
	TRegion::SubRegion(const TRegion &,TRegion *)
	TRegion::SubtractRegion(const TRegion &,TRegion *)
	TRegion::TRegion()
	TRegion::TRegion(TInt)
	TRegion::Tidy()
	TRegion::Union(const TRegion &)
	TRegion::operator[](TInt)const

Inherited Enumerations
	TRegion:@20

Private Attributes
TInt	iGranularity
TRect *	iRectangleList

Inherited Attributes
	TRegion::iAllocedRects
	TRegion::iCount
	TRegion::iError

Constructor & Destructor Documentation

RRegion(TInt, TInt)

IMPORT_C	RRegion	(	TInt	aBuf,
			TInt	aGran
		)	[protected]

Parameters

TInt aBuf
TInt aGran

RRegion()

IMPORT_C

RRegion

(

)

Default constructor.

Initialises its granularity to five.

RRegion(TInt)

IMPORT_C

RRegion

(

TInt

aGran

)

Constructs the object with the specified granularity.

Parameters

TInt aGran

The initial value for the region's granularity. This value must not be negative.

RRegion(const RRegion &)

IMPORT_C

RRegion

(

const RRegion &

aRegion

)

Copy constructor.

Constructs a new region from an existing one by performing a bit-wise copy. Both the new and existing regions are left containing pointers to the same data, so Close() must only be called on one of them.

Use of this method is not recommended.

Parameters

const RRegion & aRegion

The region to be copied.

RRegion(const TRect &, TInt)

IMPORT_C	RRegion	(	const TRect &	aRect,
			TInt	aGran = EDefaultGranularity
		)

Constructs the object with the specified rectangle and granularity.

The resulting region consists of the specified single rectangle.

Parameters

const TRect & aRect	The single rectangle with which to initialise the region
TInt aGran = EDefaultGranularity	The initial value for the region's granularity. By default, this is five.

RRegion(TInt, TRect *, TInt)

IMPORT_C	RRegion	(	TInt	aCount,
			TRect *	aRectangleList,
			TInt	aGran = EDefaultGranularity
		)

Constructor that takes ownership of an already created rectangle list.

Parameters

TInt aCount	The number of rectangles in the region.
TRect * aRectangleList	A pointer to the set of rectangles.
TInt aGran = EDefaultGranularity	The region's granularity.

Member Functions Documentation

CheckSpare()

TInt

CheckSpare

(

)

const [inline]

Gets the number of free memory slots in the region.

This is the number of slots which have been allocated, minus the number in use.

Close()

IMPORT_C void

(

)

Closes the region.

Frees up any memory which has been allocated, and unsets the error flag, if set.

The region can be re-used after calling this method. Its granularity is preserved.

Destroy()

IMPORT_C void

Destroy

(

)

Deletes the region.

Frees all memory.

Note this method will delete the RRegion object and therefore it should not be invoked on RRegion objects that are not allocated on the heap. RRegion::Close() should be used for RRegion objects stored on the stack.

panic: USER 42 if the RRegion object is stored on the stack.

Member Data Documentation

TInt iGranularity

TInt

iGranularity

[private]

TRect * iRectangleList

TRect *

iRectangleList

[private]