QDirectPainter man page on Peanut

Man page or keyword search:  
man Server   7435 pages
apropos Keyword Search (all sections)
Output format
Peanut logo
[printable version]

QDirectPainter(3qt)					   QDirectPainter(3qt)

NAME
       QDirectPainter - Direct access to the video hardware

SYNOPSIS
       #include <qdirectpainter_qws.h>

       Inherits QPainter.

   Public Members
       QDirectPainter ( const QWidget * w )
       ~QDirectPainter ()
       uchar * frameBuffer ()
       int lineStep ()
       int transformOrientation ()
       int numRects () const
       const QRect & rect ( int i ) const
       QRegion region () const
       int depth () const
       int width () const
       int height () const
       int xOffset () const
       int yOffset () const
       QPoint offset () const
       QSize size () const
       void setAreaChanged ( const QRect & r )

DESCRIPTION
       The QDirectPainter class provides direct access to the video hardware.

       Only available in Qt/Embedded.

       When the hardware is known and well defined, as is often the case with
       software for embedded devices, it may be useful to manipulate the
       underlying video hardware directly. In order to do this in a way that
       is co-operative with other applications, you must lock the video
       hardware for exclusive use for a small time while you write to it, and
       you must know the clipping region which is allocated to a widget.

       QDirectPainter provides this functionality.

       In the simplest case, you make a QDirectPainter on a widget and then,
       observing the clip region, perform some platform-specific operation.
       For example:

	       void MyWidget::updatePlatformGraphics()
	       {
		   QDirectPainter dp( this );
		   for ( int i = 0; i < dp.numRects; i++ ) {
		       const QRect& clip = dp.rect(i);
		       ... // platform specific operation
		   }
	       }

       The platform-specific code has access to the display, but should only
       modify graphics in the rectangles specified by numRects() and rect().
       Note that these rectangles are relative to the entire display.

       The offset() function returns the position of the widget relative to
       the entire display, allowing you to offset platform-specific operations
       appropriately. The xOffset() and yOffset() functions merely return the
       component values of offset().

       For simple frame-buffer hardware, the frameBuffer(), lineStep(), and
       depth() functions provide basic access, though some hardware
       configurations are insufficiently specified by such simple parameters.

       Note that while a QDirectPainter exists, the entire Qt/Embedded window
       system is locked from use by other applications. Always construct the
       QDirectPainter as an auto (stack) variable, and be very careful to
       write robust and stable code within its scope.

       See also Graphics Classes.

MEMBER FUNCTION DOCUMENTATION
QDirectPainter::QDirectPainter ( const QWidget * w )
       Construct a direct painter on w. The display is locked and the mouse
       cursor is hidden if it is above w.

QDirectPainter::~QDirectPainter ()
       Destroys the direct painter. The mouse cursor is revealed if necessary
       and the display is unlocked.

int QDirectPainter::depth () const
       Returns the bit-depth of the display.

uchar * QDirectPainter::frameBuffer ()
       Returns a pointer to the framebuffer memory if available.

int QDirectPainter::height () const
       Returns the height of the widget drawn upon.

int QDirectPainter::lineStep ()
       Returns the spacing in bytes from one framebuffer line to the next.

int QDirectPainter::numRects () const
       Returns the number of rectangles in the drawable region.

       See also rect() and region().

QPoint QDirectPainter::offset () const
       Returns the position of the widget relative to the entire display.

const QRect & QDirectPainter::rect ( int i ) const
       Returns a reference to rectangle i of the drawable region. Valid values
       for i are 0..numRects()-1.

       See also region().

QRegion QDirectPainter::region () const
       Returns the region of the framebuffer which represents the exposed area
       of the widget being painted on. Note that this may be a sub-area of the
       clip region, because of child widgets and overlapping cousin widgets.

       See also numRects() and rect().

void QDirectPainter::setAreaChanged ( const QRect & r )
       Sets the area changed by the transaction to r. By default, the entire
       widget is assumed to have changed. The area changed is only used by
       some graphics drivers, so often calling this function for a smaller
       area will make no difference to performance.

QSize QDirectPainter::size () const
       Returns the size of the widget drawn upon.

       See also width() and height().

int QDirectPainter::transformOrientation ()
       Returns a number that signifies the orientation of the framebuffer.
       <center>.nf

       </center>

int QDirectPainter::width () const
       Returns the width of the widget drawn upon.

int QDirectPainter::xOffset () const
       Returns the X-position of the widget relative to the entire display.

int QDirectPainter::yOffset () const
       Returns the Y-position of the widget relative to the entire display.

SEE ALSO
       http://doc.trolltech.com/qdirectpainter.html
       http://www.trolltech.com/faq/tech.html

COPYRIGHT
       Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com.  See the
       license file included in the distribution for a complete license
       statement.

AUTHOR
       Generated automatically from the source code.

BUGS
       If you find a bug in Qt, please report it as described in
       http://doc.trolltech.com/bughowto.html.	Good bug reports help us to
       help you. Thank you.

       The definitive Qt documentation is provided in HTML format; it is
       located at $QTDIR/doc/html and can be read using Qt Assistant or with a
       web browser. This man page is provided as a convenience for those users
       who prefer man pages, although this format is not officially supported
       by Trolltech.

       If you find errors in this manual page, please report them to qt-
       bugs@trolltech.com.  Please include the name of the manual page
       (qdirectpainter.3qt) and the Qt version (3.3.8).

Trolltech AS			2 February 2007		   QDirectPainter(3qt)
[top]

List of man pages available for Peanut

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net