Class RRegionBuf

class RRegionBuf : public RRegion;

Description

Region with pre-allocated buffer.

This class provides the functionality of an RRegion, but in addition, for optimisation purposes, uses a buffer containing pre-allocated space for as many rectangles as are specified in the granularity.

When this buffer is full, cell allocation takes place as for an RRegion, and the RRegionBuf effectively becomes an RRegion. In this case, the region does not revert to using the buffer, even if the region were to shrink so that the buffer could, once again, contain the region. When the region is no longer required, call RRegion::Close(), defined in the base class RRegion, to free up all memory.

Derivation

• TRegion - Clipping region - abstract base class.

• RRegion - Expandable region.

• RRegionBuf - Region with pre-allocated buffer.

Members

Defined in RRegionBuf:

• RRegionBuf()Constructs a default object.
• RRegionBuf(const RRegion &)Constructs this object from the specified RRegion.
• RRegionBuf(const RRegionBuf< S > &)Copy constructs from an existing RRegionBuf object.
• RRegionBuf(const TRect &)Constructs an RRegionBuf with a TRect.

Inherited from RRegion:

• CheckSpare()constGets the number of free memory slots in the region.
• Close()Closes the region.
• Destroy()Deletes the region.
• RRegion(TInt)Constructs the object with the specified granularity.
• RRegion(TInt,TInt)
• RRegion(TInt,TRect *,TInt)Constructor that takes ownership of an already created rectangle list.
• RRegion(const RRegion &)Copy constructor.
• RRegion(const TRect &,TInt)Constructs the object with the specified rectangle and granularity.

Inherited from TRegion:

• AddRect(const TRect &)Adds a rectangle to this region.
• BoundingRect()constGets the minimal rectangle that bounds the entire region.
• CheckError()constTests whether the region's error flag is set.
• Clear()Clears this region.
• ClipRect(const TRect &)Clips the region to the specified rectangle.
• Contains(const TPoint &)constTests whether a point is located within the region.
• Copy(const TRegion &)Copies another region to this region.
• Count()constGets the number of rectangles in this region.
• ERRegionBuf
• ForceError()Sets the error flag, and clears the region.
• Intersect(const TRegion &)Replaces this region with the area of intersection between it and the specified ...
• Intersection(const TRegion &,const TRegion &)Replaces this region with the area of intersection between two specified regions...
• Intersects(const TRect &)constTests whether where there is any intersection between this region and the specif...
• IsContainedBy(const TRect &)constTests whether the region is fully enclosed within the specified rectangle.
• IsEmpty()constTests whether the region is empty.
• Offset(TInt,TInt)Moves the region by adding X and Y offsets to the co-ordinates of its corners.
• Offset(const TPoint &)Moves the region by adding a TPoint offset to the co-ordinates of its corners.
• RectangleList()constGets a pointer to the array of rectangles defining this region.
• RectangleListW()
• Sort()Sorts the region's array of rectangles according to their vertical position on t...
• Sort(const TPoint &)Sorts the region's array of rectangles according to a specified sort order.
• SubRect(const TRect &,TRegion *)Removes a rectangle from this region.
• SubRegion(const TRegion &,TRegion *)Removes a region.
• TRegion(TInt)
• Tidy()Merges all rectangles within this region which share an adjacent edge of the sam...
• Union(const TRegion &)Replaces this region with the union of it and the specified region.
• anonymous
• iAllocedRects
• iCount
• iError
• operator[](TInt)constGets a rectangle from the region.

inline RRegionBuf();

Description

Constructs a default object.

The granularity is the value of the template parameter.

inline RRegionBuf(const RRegion &aRegion);

Description

Constructs this object from the specified RRegion.

Parameters

const RRegion &aRegion The region to assign to this RRegionBuf.

inline RRegionBuf(const RRegionBuf< S > &aRegion);

Description

Copy constructs from an existing RRegionBuf object.

Parameters

const RRegionBuf< S > &aRegion The RRegionBuf to be copied.

inline RRegionBuf(const TRect &aRect);

Description

Constructs an RRegionBuf with a TRect.

Its granularity is initialised to the value contained in the template argument. The resulting region consists of the specified single rectangle.

Parameters

const TRect &aRect The single rectangle with which to initialise the region.