QwtPaintBuffer Class Reference

#include <qwt_paint_buffer.h>

Collaboration diagram for QwtPaintBuffer:

[legend]List of all members.

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Detailed Description

Paint buffer for Qwt widgets.

QwtPaintBuffer offers a simple way to en/disable double buffering. Double buffering is enabled as default and in general there will be no reason to change this.

Definition at line 36 of file qwt_paint_buffer.h.

Public Member Functions
void	close ()
const QPaintDevice *	device ()
void	open (QPaintDevice *, const QRect &, QPainter *painter=NULL)
QPainter *	painter ()
	QwtPaintBuffer (QPaintDevice *, const QRect &, QPainter *painter=NULL)
	QwtPaintBuffer ()
	Default constructor.
virtual	~QwtPaintBuffer ()
Static Public Member Functions
static bool	isEnabled ()
static void	setEnabled (bool enable)
Protected Member Functions
void	flush ()
Private Attributes
QPaintDevice *	d_device
QPainter *	d_devicePainter
QPainter *	d_painter
QPixmap	d_pixBuffer
QRect	d_rect
Static Private Attributes
static bool	d_enabled = TRUE

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Constructor & Destructor Documentation

QwtPaintBuffer::QwtPaintBuffer (   )

Default constructor. Definition at line 38 of file qwt_paint_buffer.cpp.

QwtPaintBuffer::QwtPaintBuffer (  QPaintDevice *  device, const QRect &  rect, QPainter *  painter = NULL )

Create an open paint buffer Parameters: device  Device to paint on rect  Rect to paint on painter  Painter to paint on device. In case of 0 QwtPaintBuffer uses an internal painter See also: QwtPaintBuffer::open() Definition at line 55 of file qwt_paint_buffer.cpp. References open().

QwtPaintBuffer::~QwtPaintBuffer (   )  [virtual]

Closes the buffer See also: QwtPaintBuffer::close() Definition at line 68 of file qwt_paint_buffer.cpp. References close().

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Member Function Documentation

void QwtPaintBuffer::close (   )

Flush the internal pixmap buffer to the device and close the buffer. Definition at line 199 of file qwt_paint_buffer.cpp. References d_device, d_devicePainter, d_painter, d_pixBuffer, QPainter::end(), flush(), QPainter::isActive(), and QPixmap::isNull(). Referenced by open(), and ~QwtPaintBuffer().

const QPaintDevice * QwtPaintBuffer::device (   )

Returns: Device to paint on Definition at line 87 of file qwt_paint_buffer.cpp. References d_device. Referenced by flush().

void QwtPaintBuffer::flush (   )  [protected]

Flush the internal pixmap buffer to the device. Definition at line 172 of file qwt_paint_buffer.cpp. References d_device, d_devicePainter, d_enabled, d_pixBuffer, d_rect, QPainter::device(), device(), QPainter::drawPixmap(), QPaintDevice::isExtDev(), QRect::isValid(), and QRect::topLeft(). Referenced by close().

bool QwtPaintBuffer::isEnabled (   )  [static]

Returns: TRUE if double buffering is enabled, FALSE otherwise. Definition at line 105 of file qwt_paint_buffer.cpp. References d_enabled. Referenced by open().

void QwtPaintBuffer::open (  QPaintDevice *  device, const QRect &  rect, QPainter *  painter = NULL )

Open the buffer Parameters: device  Device to paint on rect  Rect to paint on painter  Painter to paint on device. In case of 0 QwtPaintBuffer uses an internal painter Definition at line 118 of file qwt_paint_buffer.cpp. References QPainter::begin(), close(), d_device, d_devicePainter, d_painter, d_pixBuffer, d_rect, QPainter::eraseRect(), QPixmap::fill(), isEnabled(), QRect::isValid(), QPixmap::resize(), QRect::size(), QWidget::testWFlags(), QRect::topLeft(), QPainter::translate(), QRect::x(), and QRect::y(). Referenced by QwtPaintBuffer().

QPainter * QwtPaintBuffer::painter (   )

Returns: Depending on isEnabled() the painter connected to an internal pixmap buffer otherwise the painter connected to the device. Definition at line 79 of file qwt_paint_buffer.cpp. References d_painter. Referenced by QtViewWidget::paintEvent().

void QwtPaintBuffer::setEnabled (  bool  enable  )  [static]

Enable/Disable double buffering. Please note that this is a global switch for all QwtPaintBuffers, but won't change opened buffers. Definition at line 97 of file qwt_paint_buffer.cpp. References d_enabled.

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Member Data Documentation

QPaintDevice* QwtPaintBuffer::d_device [private]

Definition at line 60 of file qwt_paint_buffer.h. Referenced by close(), device(), flush(), and open().

QPainter* QwtPaintBuffer::d_devicePainter [private]

Definition at line 62 of file qwt_paint_buffer.h. Referenced by close(), flush(), and open().

bool QwtPaintBuffer::d_enabled = TRUE [static, private]

Definition at line 32 of file qwt_paint_buffer.cpp. Referenced by flush(), isEnabled(), and setEnabled().

QPainter* QwtPaintBuffer::d_painter [private]

Definition at line 61 of file qwt_paint_buffer.h. Referenced by close(), open(), and painter().

QPixmap QwtPaintBuffer::d_pixBuffer [private]

Definition at line 57 of file qwt_paint_buffer.h. Referenced by close(), flush(), and open().

QRect QwtPaintBuffer::d_rect [private]

Definition at line 58 of file qwt_paint_buffer.h. Referenced by flush(), and open().

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The documentation for this class was generated from the following files:

• qwt_paint_buffer.h
• qwt_paint_buffer.cpp

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