Viadeo Twitter Google Bookmarks ! Facebook Digg del.icio.us MySpace Yahoo MyWeb Blinklist Netvouz Reddit Simpy StumbleUpon Bookmarks Windows Live Favorites 
Logo Documentation Qt ·  Page d'accueil  ·  Toutes les classes  ·  Toutes les fonctions  ·  Vues d'ensemble  · 

QRasterPaintEngine Class Reference
[QtGui module]

The QRasterPaintEngine class enables hardware acceleration of painting operations in Qt for Embedded Linux. More...

 #include <QRasterPaintEngine>

This class is under development and is subject to change.

Inherits QPaintEngine.

This class was introduced in Qt 4.2.


Public Functions

QRasterPaintEngine ( QPaintDevice * device )
~QRasterPaintEngine ()
virtual void drawBufferSpan ( const uint * buffer, int size, int x, int y, int length, uint alpha )
virtual void drawColorSpans ( const QSpan * spans, int count, uint color )

Reimplemented Public Functions

virtual bool begin ( QPaintDevice * device )
virtual void drawEllipse ( const QRectF & rect )
virtual void drawEllipse ( const QRect & rect )
virtual void drawImage ( const QRectF & r, const QImage & img, const QRectF & sr, Qt::ImageConversionFlags falgs = Qt::AutoColor )
virtual void drawLines ( const QLine * lines, int lineCount )
virtual void drawLines ( const QLineF * lines, int lineCount )
virtual void drawPixmap ( const QRectF & r, const QPixmap & pixmap, const QRectF & sr )
virtual void drawPoints ( const QPointF * points, int pointCount )
virtual void drawPoints ( const QPoint * points, int pointCount )
virtual void drawPolygon ( const QPointF * points, int pointCount, PolygonDrawMode mode )
virtual void drawPolygon ( const QPoint * points, int pointCount, PolygonDrawMode mode )
virtual void drawRects ( const QRect * rects, int rectCount )
virtual void drawRects ( const QRectF * rects, int rectCount )
virtual void drawTextItem ( const QPointF & p, const QTextItem & textItem )
virtual void drawTiledPixmap ( const QRectF & r, const QPixmap & pixmap, const QPointF & sr )
virtual bool end ()
virtual void fillRect ( const QRectF & r, const QBrush & brush )
virtual void fillRect ( const QRectF & r, const QColor & color )
virtual Type type () const

Related Non-Members

typedef QSpan

Detailed Description

The QRasterPaintEngine class enables hardware acceleration of painting operations in Qt for Embedded Linux.

Note that this functionality is only available in Qt for Embedded Linux.

In Qt for Embedded Linux, painting is a pure software implementation. But starting with Qt 4.2, it is possible to add an accelerated graphics driver to take advantage of available hardware resources.

Hardware acceleration is accomplished by creating a custom screen driver, accelerating the copying from memory to the screen, and implementing a custom paint engine accelerating the various painting operations. Then a custom paint device (derived from the QCustomRasterPaintDevice class) and a custom window surface (derived from QWSWindowSurface) must be implemented to make Qt for Embedded Linux aware of the accelerated driver.

Note: The QRasterPaintEngine class does not support 8-bit images. Instead, they need to be converted to a supported format, such as QImage::Format_ARGB32_Premultiplied.

See the Adding an Accelerated Graphics Driver to Qt for Embedded Linux documentation for details.

See also QCustomRasterPaintDevice and QPaintEngine.


Member Function Documentation

QRasterPaintEngine::QRasterPaintEngine ( QPaintDevice * device )

Creates a raster based paint engine for operating on the given device, with the complete set of paint engine features and capabilities.

This function was introduced in Qt 4.5.

QRasterPaintEngine::~QRasterPaintEngine ()

Destroys this paint engine.

bool QRasterPaintEngine::begin ( QPaintDevice * device )   [virtual]

Reimplemented from QPaintEngine::begin().

void QRasterPaintEngine::drawBufferSpan ( const uint * buffer, int size, int x, int y, int length, uint alpha )   [virtual]

Draws the given buffer.

The default implementation does nothing; reimplement this function to draw a buffer that contains more than one color. Note that this function must be reimplemented if the framebuffer is not memory-mapped.

The size parameter specifies the total size of the given buffer, while the length parameter specifies the number of pixels to draw. The buffer's position is given by (x, y). The provided alpha value is added to each pixel in the buffer when drawing.

See also drawColorSpans().

void QRasterPaintEngine::drawColorSpans ( const QSpan * spans, int count, uint color )   [virtual]

Draws the given color spans with the specified color. The count parameter specifies the number of spans.

The default implementation does nothing; reimplement this function to draw the given color spans with the specified color. Note that this function must be reimplemented if the framebuffer is not memory-mapped.

See also drawBufferSpan().

void QRasterPaintEngine::drawEllipse ( const QRectF & rect )   [virtual]

Reimplemented from QPaintEngine::drawEllipse().

void QRasterPaintEngine::drawEllipse ( const QRect & rect )   [virtual]

Reimplemented from QPaintEngine::drawEllipse().

This is an overloaded function.

Reimplement this function to draw the largest ellipse that can be contained within rectangle rect.

void QRasterPaintEngine::drawImage ( const QRectF & r, const QImage & img, const QRectF & sr, Qt::ImageConversionFlags falgs = Qt::AutoColor )   [virtual]

Reimplemented from QPaintEngine::drawImage().

void QRasterPaintEngine::drawLines ( const QLine * lines, int lineCount )   [virtual]

Reimplemented from QPaintEngine::drawLines().

void QRasterPaintEngine::drawLines ( const QLineF * lines, int lineCount )   [virtual]

Reimplemented from QPaintEngine::drawLines().

void QRasterPaintEngine::drawPixmap ( const QRectF & r, const QPixmap & pixmap, const QRectF & sr )   [virtual]

Reimplemented from QPaintEngine::drawPixmap().

void QRasterPaintEngine::drawPoints ( const QPointF * points, int pointCount )   [virtual]

Reimplemented from QPaintEngine::drawPoints().

void QRasterPaintEngine::drawPoints ( const QPoint * points, int pointCount )   [virtual]

Reimplemented from QPaintEngine::drawPoints().

This is an overloaded function.

Draws the first pointCount points in the buffer points

The default implementation converts the first pointCount QPoints in points to QPointFs and calls the floating point version of drawPoints.

void QRasterPaintEngine::drawPolygon ( const QPointF * points, int pointCount, PolygonDrawMode mode )   [virtual]

Reimplemented from QPaintEngine::drawPolygon().

void QRasterPaintEngine::drawPolygon ( const QPoint * points, int pointCount, PolygonDrawMode mode )   [virtual]

Reimplemented from QPaintEngine::drawPolygon().

void QRasterPaintEngine::drawRects ( const QRect * rects, int rectCount )   [virtual]

Reimplemented from QPaintEngine::drawRects().

void QRasterPaintEngine::drawRects ( const QRectF * rects, int rectCount )   [virtual]

Reimplemented from QPaintEngine::drawRects().

void QRasterPaintEngine::drawTextItem ( const QPointF & p, const QTextItem & textItem )   [virtual]

Reimplemented from QPaintEngine::drawTextItem().

void QRasterPaintEngine::drawTiledPixmap ( const QRectF & r, const QPixmap & pixmap, const QPointF & sr )   [virtual]

Reimplemented from QPaintEngine::drawTiledPixmap().

bool QRasterPaintEngine::end ()   [virtual]

Reimplemented from QPaintEngine::end().

void QRasterPaintEngine::fillRect ( const QRectF & r, const QBrush & brush )   [virtual]

void QRasterPaintEngine::fillRect ( const QRectF & r, const QColor & color )   [virtual]

Type QRasterPaintEngine::type () const   [virtual]

Reimplemented from QPaintEngine::type().


Related Non-Members

typedef QSpan

A struct equivalent to QT_FT_Span, containing a position (x, y), the span's length in pixels and its color/coverage (a value ranging from 0 to 255).

Publicité

Best Of

Actualités les plus lues

Semaine
Mois
Année
  1. « Quelque chose ne va vraiment pas avec les développeurs "modernes" », un développeur à "l'ancienne" critique la multiplication des bibliothèques 44
  2. Microsoft ouvre aux autres compilateurs C++ AMP, la spécification pour la conception d'applications parallèles C++ utilisant le GPU 22
  3. Les développeurs ignorent-ils trop les failles découvertes dans leur code ? Prenez-vous en compte les remarques des autres ? 17
  4. RIM : « 13 % des développeurs ont gagné plus de 100 000 $ sur l'AppWord », Qt et open-source au menu du BlackBerry DevCon Europe 0
  5. BlackBerry 10 : premières images du prochain OS de RIM qui devrait intégrer des widgets et des tuiles inspirées de Windows Phone 0
  6. Quelles nouveautés de C++11 Visual C++ doit-il rapidement intégrer ? Donnez-nous votre avis 10
  7. Adieu qmake, bienvenue qbs : Qt Building Suite, un outil déclaratif et extensible pour la compilation de projets Qt 17
Page suivante

Le blog Digia au hasard

Logo

Déploiement d'applications Qt Commercial sur les tablettes Windows 8

Le blog Digia est l'endroit privilégié pour la communication sur l'édition commerciale de Qt, où des réponses publiques sont apportées aux questions les plus posées au support. Lire l'article.

Communauté

Ressources

Liens utiles

Contact

  • Vous souhaitez rejoindre la rédaction ou proposer un tutoriel, une traduction, une question... ? Postez dans le forum Contribuez ou contactez-nous par MP ou par email (voir en bas de page).

Qt dans le magazine

Cette page est une traduction d'une page de la documentation de Qt, écrite par Nokia Corporation and/or its subsidiary(-ies). Les éventuels problèmes résultant d'une mauvaise traduction ne sont pas imputables à Nokia. Qt 4.6
Copyright © 2012 Developpez LLC. Tous droits réservés Developpez LLC. Aucune reproduction, même partielle, ne peut être faite de ce site et de l'ensemble de son contenu : textes, documents et images sans l'autorisation expresse de Developpez LLC. Sinon, vous encourez selon la loi jusqu'à 3 ans de prison et jusqu'à 300 000 E de dommages et intérêts. Cette page est déposée à la SACD.
Vous avez déniché une erreur ? Un bug ? Une redirection cassée ? Ou tout autre problème, quel qu'il soit ? Ou bien vous désirez participer à ce projet de traduction ? N'hésitez pas à nous contacter ou par MP !
 
 
 
 
Partenaires

Hébergement Web