BRegion Class Reference

#include <Region.h>

Detailed Description

A BRegion object comprises a set of rectangles in a two-dimensional coordinate system.

See also:: Using BRegion

Public Member Functions

BRegion ()

BRegion (const BRegion &region)

BRegion (const BRect rect)

virtual ~BRegion ()

BRegion & operator= (const BRegion &from)

BRect Frame () const

clipping_rect FrameInt () const

BRect RectAt (int32 index) const

clipping_rect RectAtInt (int32 index) const

int32 CountRects () const

void Set (BRect newBounds)

void Set (clipping_rect newBounds)

bool Intersects (BRect r) const

bool Intersects (clipping_rect r) const

bool Contains (BPoint pt) const

bool Contains (int32 x, int32 y)

void PrintToStream () const

void OffsetBy (int32 dh, int32 dv)

void MakeEmpty ()

void Include (BRect r)

void Include (clipping_rect r)

void Include (const BRegion *)

void Exclude (BRect r)

void Exclude (clipping_rect r)

void Exclude (const BRegion *)

void IntersectWith (const BRegion *)

BRegion (BPrivate::IRegion *reg, bool takeOwnership=true)

Friends

class BPrivate::IKAccess

Constructor & Destructor Documentation

BRegion ( )

Default constructor.
If no argument is supplied, the BRegion is empty and Frame() returns and invalid BRect.

BRegion ( const BRegion & reg )

Initializes the BRegion object to be a copy of region.

Parameters:

reg Region

BRegion ( const BRect rect )

Initializes the BRegion object to be a rectangular region containing the space indicated by rect.

~BRegion ( ) [virtual]

Frees the memory that was allocated to hold data describing the region.

BRegion ( BPrivate::IRegion * reg,

bool takeOwnership = true

)

Member Function Documentation

bool Contains ( int32 x,

int32 y

)

bool Contains ( BPoint a_point ) const

Returns:
true if point lies within the region, and false if not.

int32 CountRects ( ) const

/return the total number of rectangles in the BRegion.

void Exclude ( const BRegion * region )

Modifies the region to exclude all rectangles contained in region.
region Region to exclude

void Exclude ( clipping_rect r )

void Exclude ( BRect fr )

Modifies the region to exclude all rectangles contained in rect.
fr Rectangle to exclude

BRect Frame ( ) const

Returns the smallest rectangle that encloses all the rectangles in the region.
If the region is empty, the returned object will be invalid. Check the return thus.

See also:
BRect::IsValid()

clipping_rect FrameInt ( ) const

void Include ( const BRegion * region )

Modifies the region to include (copies of) the rectangles contained in region.
region Region to include

void Include ( clipping_rect r )

void Include ( BRect fr )

Modifies the region to include (copies of) the rectangles contained in rect.

Parameters:

fr Rectangle to include

bool Intersects ( clipping_rect r ) const

bool Intersects ( BRect a_rect ) const

Returns:
true if the BRegion has any area in common with rect, and false if not.

void IntersectWith ( const BRegion * region )

Modifies the region so that it includes only those areas that it has in common with another region.

Parameters:

region Intersection region

void MakeEmpty ( )

Empties the BRegion and invalidates the object's Frame() rectangle.

void OffsetBy ( int32 dh,

int32 dv

)

Offsets all rectangles in the region by horizontal and vertical deltas.

Parameters:

dh horizontal delta

dv vertical delta

BRegion & operator= ( const BRegion & from )

Sets the left region to be an independent copy of the right region:
BRegion left_region = right_region;

void PrintToStream ( void ) const

Prints (to standard out) each rectangle in the BRegion in the form:
"BRect(left, top, right, bottom)"
The first string that's printed is the object's frame rectangle. Each subsequent string describes a single rectangle in the BRegion.

BRect RectAt ( int32 index ) const

Returns:
the rectangle at a particular index. The order of the rectangles is unimportant.

Parameters:

index particular index

clipping_rect RectAtInt ( int32 index ) const

void Set ( clipping_rect newBounds )

void Set ( BRect initialbound )

Modifies the BRegion so that it only contains rect.

Parameters:

initialbound Initial rectangle

Friends And Related Function Documentation

friend class BPrivate::IKAccess [friend]


Public Member Functions
	BRegion ()
	BRegion (const BRegion &region)
	BRegion (const BRect rect)
virtual	~BRegion ()
BRegion &	operator= (const BRegion &from)
BRect	Frame () const
clipping_rect	FrameInt () const
BRect	RectAt (int32 index) const
clipping_rect	RectAtInt (int32 index) const
int32	CountRects () const
void	Set (BRect newBounds)
void	Set (clipping_rect newBounds)
bool	Intersects (BRect r) const
bool	Intersects (clipping_rect r) const
bool	Contains (BPoint pt) const
bool	Contains (int32 x, int32 y)
void	PrintToStream () const
void	OffsetBy (int32 dh, int32 dv)
void	MakeEmpty ()
void	Include (BRect r)
void	Include (clipping_rect r)
void	Include (const BRegion *)
void	Exclude (BRect r)
void	Exclude (clipping_rect r)
void	Exclude (const BRegion *)
void	IntersectWith (const BRegion *)
	BRegion (BPrivate::IRegion *reg, bool takeOwnership=true)
Friends
class	BPrivate::IKAccess