wxPen Class Reference
[Graphics Device Interface (GDI)]

#include <wx/pen.h>

Inheritance diagram for wxPen:
Inheritance graph
[legend]

Detailed Description

A pen is a drawing tool for drawing outlines.

It is used for drawing lines and painting the outline of rectangles, ellipses, etc. It has a colour, a width and a style.

Note:
On a monochrome display, wxWidgets shows all non-white pens as black.

Do not initialize objects on the stack before the program commences, since other required structures may not have been set up yet. Instead, define global pointers to objects and create them in wxApp::OnInit() or when required.

An application may wish to dynamically create pens with different characteristics, and there is the consequent danger that a large number of duplicate pens will be created. Therefore an application may wish to get a pointer to a pen by using the global list of pens wxThePenList, and calling the member function wxPenList::FindOrCreatePen(). See wxPenList for more info.

This class uses reference counting and copy-on-write internally so that assignments between two instances of this class are very cheap. You can therefore use actual objects instead of pointers without efficiency problems. If an instance of this class is changed it will create its own data internally so that other instances, which previously shared the data using the reference counting, are not affected.

Library:  wxCore
Category:  Graphics Device Interface (GDI)

Predefined objects/pointers:

See also:
wxPenList, wxDC, wxDC::SetPen()

Public Member Functions

 wxPen ()
 Default constructor.
 wxPen (const wxColour &colour, int width=1, wxPenStyle style=wxPENSTYLE_SOLID)
 Constructs a pen from a colour object, pen width and style.
 wxPen (const wxBitmap &stipple, int width)
 Constructs a stippled pen from a stipple bitmap and a width.
 wxPen (const wxPen &pen)
 Copy constructor, uses Reference Counting.
virtual ~wxPen ()
 Destructor.
virtual wxPenCap GetCap () const
 Returns the pen cap style, which may be one of wxCAP_ROUND, wxCAP_PROJECTING and wxCAP_BUTT.
virtual wxColour GetColour () const
 Returns a reference to the pen colour.
virtual int GetDashes (wxDash **dashes) const
 Gets an array of dashes (defined as char in X, DWORD under Windows).
virtual wxPenJoin GetJoin () const
 Returns the pen join style, which may be one of wxJOIN_BEVEL, wxJOIN_ROUND and wxJOIN_MITER.
virtual wxBitmapGetStipple () const
 Gets a pointer to the stipple bitmap.
virtual wxPenStyle GetStyle () const
 Returns the pen style.
virtual int GetWidth () const
 Returns the pen width.
virtual bool IsOk () const
 Returns true if the pen is initialised.
virtual void SetCap (wxPenCap capStyle)
 Sets the pen cap style, which may be one of wxCAP_ROUND, wxCAP_PROJECTING and wxCAP_BUTT.
virtual void SetDashes (int n, const wxDash *dash)
 Associates an array of pointers to dashes (defined as char in X, DWORD under Windows) with the pen.
virtual void SetJoin (wxPenJoin join_style)
 Sets the pen join style, which may be one of wxJOIN_BEVEL, wxJOIN_ROUND and wxJOIN_MITER.
virtual void SetStipple (const wxBitmap &stipple)
 Sets the bitmap for stippling.
virtual void SetStyle (wxPenStyle style)
 Set the pen style.
virtual void SetWidth (int width)
 Sets the pen width.
bool operator!= (const wxPen &pen) const
 Inequality operator.
wxPenoperator= (const wxPen &pen)
 Assignment operator, using Reference Counting.
bool operator== (const wxPen &pen) const
 Equality operator.

virtual void SetColour (wxColour &colour)
 The pen's colour is changed to the given colour.
virtual void SetColour (unsigned char red, unsigned char green, unsigned char blue)
 The pen's colour is changed to the given colour.

List of all members.


Constructor & Destructor Documentation

wxPen::wxPen (  ) 

Default constructor.

The pen will be uninitialised, and IsOk() will return false.

wxPen::wxPen ( const wxColour colour,
int  width = 1,
wxPenStyle  style = wxPENSTYLE_SOLID 
)

Constructs a pen from a colour object, pen width and style.

Parameters:
colour A colour object.
width Pen width. Under Windows, the pen width cannot be greater than 1 if the style is wxPENSTYLE_DOT, wxPENSTYLE_LONG_DASH, wxPENSTYLE_SHORT_DASH, wxPENSTYLE_DOT_DASH, or wxPENSTYLE_USER_DASH.
style The style may be one of the wxPenStyle values.
Remarks:
Different versions of Windows and different versions of other platforms support very different subsets of the styles above
  • there is no similarity even between Windows95 and Windows98 - so handle with care.
See also:
SetStyle(), SetColour(), SetWidth()
wxPen::wxPen ( const wxBitmap stipple,
int  width 
)

Constructs a stippled pen from a stipple bitmap and a width.

Parameters:
width Pen width. Under Windows, the pen width cannot be greater than 1 if the style is wxPENSTYLE_DOT, wxPENSTYLE_LONG_DASH, wxPENSTYLE_SHORT_DASH, wxPENSTYLE_DOT_DASH, or wxPENSTYLE_USER_DASH.
stipple A stipple bitmap.
Availability:  only available for the wxMSW, wxOSX ports.
See also:
SetWidth(), SetStipple()
wxPen::wxPen ( const wxPen pen  ) 

Copy constructor, uses Reference Counting.

Parameters:
pen A pointer or reference to a pen to copy.
virtual wxPen::~wxPen (  )  [virtual]

Destructor.

See also:
reference-counted object destruction
Remarks:
Although all remaining pens are deleted when the application exits, the application should try to clean up all pens itself. This is because wxWidgets cannot know if a pointer to the pen object is stored in an application data structure, and there is a risk of double deletion.

Member Function Documentation

virtual wxPenCap wxPen::GetCap (  )  const [virtual]

Returns the pen cap style, which may be one of wxCAP_ROUND, wxCAP_PROJECTING and wxCAP_BUTT.

The default is wxCAP_ROUND.

See also:
SetCap()
virtual wxColour wxPen::GetColour (  )  const [virtual]

Returns a reference to the pen colour.

See also:
SetColour()
virtual int wxPen::GetDashes ( wxDash **  dashes  )  const [virtual]

Gets an array of dashes (defined as char in X, DWORD under Windows).

dashes is a pointer to the internal array. Do not deallocate or store this pointer.

Returns:
The number of dashes associated with this pen.
See also:
SetDashes()
virtual wxPenJoin wxPen::GetJoin (  )  const [virtual]

Returns the pen join style, which may be one of wxJOIN_BEVEL, wxJOIN_ROUND and wxJOIN_MITER.

The default is wxJOIN_ROUND.

See also:
SetJoin()
virtual wxBitmap* wxPen::GetStipple (  )  const [virtual]

Gets a pointer to the stipple bitmap.

See also:
SetStipple()
virtual wxPenStyle wxPen::GetStyle (  )  const [virtual]

Returns the pen style.

See also:
wxPen(), SetStyle()
virtual int wxPen::GetWidth (  )  const [virtual]

Returns the pen width.

See also:
SetWidth()
virtual bool wxPen::IsOk (  )  const [virtual]

Returns true if the pen is initialised.

bool wxPen::operator!= ( const wxPen pen  )  const

Inequality operator.

See reference-counted object comparison for more info.

wxPen& wxPen::operator= ( const wxPen pen  ) 

Assignment operator, using Reference Counting.

bool wxPen::operator== ( const wxPen pen  )  const

Equality operator.

See reference-counted object comparison for more info.

virtual void wxPen::SetCap ( wxPenCap  capStyle  )  [virtual]

Sets the pen cap style, which may be one of wxCAP_ROUND, wxCAP_PROJECTING and wxCAP_BUTT.

The default is wxCAP_ROUND.

See also:
GetCap()
virtual void wxPen::SetColour ( unsigned char  red,
unsigned char  green,
unsigned char  blue 
) [virtual]

The pen's colour is changed to the given colour.

See also:
GetColour()
virtual void wxPen::SetColour ( wxColour colour  )  [virtual]

The pen's colour is changed to the given colour.

See also:
GetColour()
virtual void wxPen::SetDashes ( int  n,
const wxDash *  dash 
) [virtual]

Associates an array of pointers to dashes (defined as char in X, DWORD under Windows) with the pen.

The array is not deallocated by wxPen, but neither must it be deallocated by the calling application until the pen is deleted or this function is called with a NULL array.

See also:
GetDashes()
virtual void wxPen::SetJoin ( wxPenJoin  join_style  )  [virtual]

Sets the pen join style, which may be one of wxJOIN_BEVEL, wxJOIN_ROUND and wxJOIN_MITER.

The default is wxJOIN_ROUND.

See also:
GetJoin()
virtual void wxPen::SetStipple ( const wxBitmap stipple  )  [virtual]

Sets the bitmap for stippling.

See also:
GetStipple()
virtual void wxPen::SetStyle ( wxPenStyle  style  )  [virtual]

Set the pen style.

See also:
wxPen()
virtual void wxPen::SetWidth ( int  width  )  [virtual]

Sets the pen width.

See also:
GetWidth()
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