QScreen(3qt)

NAME
QScreen - Abstracts the interface to the framebuffer

#include <qgfx_qws.h>

  Public Members
QScreen ( int display_id )
virtual ~QScreen ()
virtual bool initDevice ()
virtual bool connect ( const QString & displaySpec )
virtual void disconnect ()
virtual int initCursor ( void *, bool=FALSE )
virtual void shutdownDevice ()
virtual void setMode ( int, int, int )
virtual bool supportsDepth ( int ) const
virtual QGfx* createGfx ( unsigned char *, int, int, int, int )
virtual QGfx* screenGfx ()
virtual void save ()
virtual void restore ()
virtual void blank ( bool on )
virtual int pixmapOffsetAlignment ()
virtual int pixmapLinestepAlignment ()
virtual bool onCard ( unsigned char * ) const
virtual bool onCard ( unsigned char *, ulong & out_offset ) const
virtual void set ( unsigned int, unsigned int, unsigned int, unsigned int )
virtual int alloc ( unsigned int, unsigned int, unsigned int )
int width () const
int height () const
int depth () const
virtual int pixmapDepth () const
int pixelType () const
int linestep () const
int deviceWidth () const
int deviceHeight () const
uchar* base () const
virtual uchar* cache ( int, int )
virtual void uncache ( uchar * )
int screenSize () const
int totalSize () const
QRgb* clut ()
int numCols ()
virtual QSize mapToDevice ( const QSize & ) const
virtual QSize mapFromDevice ( const QSize & ) const
virtual QPoint mapToDevice ( const QPoint &, const QSize & ) const
virtual QPoint mapFromDevice ( const QPoint &, const QSize & ) const
virtual QRect mapToDevice ( const QRect &, const QSize & ) const
virtual QRect mapFromDevice ( const QRect &, const QSize & ) const
virtual QImage mapToDevice ( const QImage & ) const
virtual QImage mapFromDevice ( const QImage & ) const
virtual QRegion mapToDevice ( const QRegion &, const QSize & ) const
virtual QRegion mapFromDevice ( const QRegion &, const QSize & ) const
virtual int transformOrientation () const
virtual bool isTransformed () const
virtual bool isInterlaced () const

DESCRIPTION
The QScreen class abstracts the interface to the framebuffer.

Descendants of QScreen manage the framebuffer and palette and act as factories for the screen cursor and QGfx's. QLinuxFbScreen manages a Linux framebuffer; accelerated drivers subclass QLinuxFbScreen. There can only be one screen in a Qt/Embedded application.

MEMBER FUNCTION DOCUMENTATION

QScreen::QScreen ( int display_id )
Create a screen; the display_id is the number of the Qt/Embedded server to connect to.

QScreen::~QScreen () [virtual]
Destroys a QScreen.

int QScreen::alloc ( unsigned int r,unsigned int g,unsigned int b ) [virtual]
Given an RGB value, return an index which is the closest match to it in the screen's palette. Used in paletted modes only.

int QScreen::initCursor ( void * end_of_location, bool init=FALSE ) [virtual]
This is used to initialise the software cursor - end_of_location points to the address after the area where the cursor image can be stored. init is true for the first application this method is called from (the Qt/Embedded server), false otherwise.

bool QScreen::onCard ( unsigned char * p ) const [virtual]
Returns true if the buffer pointed to by p is within graphics card memory, false if it's in main RAM.

bool QScreen::onCard ( unsigned char * p, ulong & offset ) const [virtual]
This checks whether the buffer specified by p is on the card (as per the other version of onCard) and returns an offset in bytes from the start of graphics card memory in offset if it is.

int QScreen::pixelType () const
Returns an integer (taking the same values as QGfx::PixelType) that specifies the pixel storage format of the screen.

void QScreen::restore () [virtual]
Restore the state of the graphics card from a previous save().

void QScreen::save () [virtual]
Saves the state of the graphics card - used so that, for instance, the palette can be restored when switching between linux virtual consoles. Hardware QScreen descendants should save register state here if necessary if switching between virtual consoles (for example to/from X) is to be permitted.

QGfx * QScreen::screenGfx () [virtual]
Returns a QGfx (normally a QGfxRaster) initialised to point to the screen, with an origin at 0,0 and a clip region covering the whole screen.

void QScreen::set ( unsigned int, unsigned int, unsigned int, unsigned int ) [virtual]
Set an entry in the colour palette. A noop in this class, implemented in QLinuxFbScreen.

void QScreen::shutdownDevice () [virtual]
Called by the Qt/Embedded server on shutdown; never called by a Qt/Embedded client. This is intended to support graphics card specific shutdown; the unaccelerated implementation simply hides the mouse cursor.

bool QScreen::supportsDepth ( int d ) const [virtual]
Returns true if the screen supports a particular color depth. Possible values are 1,4,8,16 and 32.

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

COPYRIGHT
Copyright 1992-2001 Trolltech AS, 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 make our job much simpler. Thank you.

In case of content or formattting problems with this manual page, please report them to qt-bugs@trolltech.com. Please include the name of the manual page (qscreen.3qt) and the Qt version (2.3.10).