QRasterPaintEngine Class
The QRasterPaintEngine class enables hardware acceleration of painting operations in Qt for Embedded Linux. More...
| Header: | #include <QRasterPaintEngine> |
| CMake: | find_package(Qt6 COMPONENTS Gui REQUIRED) target_link_libraries(mytarget PRIVATE Qt6::Gui) |
| qmake: | QT += gui |
| Inherits: | QPaintEngineEx |
This class is under development and is subject to change.
Public Functions
| QRasterPaintEngine(QPaintDevice *device) | |
| virtual | ~QRasterPaintEngine() |
Reimplemented Public Functions
| virtual bool | begin(QPaintDevice *device) override |
| virtual void | drawEllipse(const QRectF &rect) override |
| virtual void | drawImage(const QRectF &r, const QImage &img, const QRectF &sr, Qt::ImageConversionFlags flags = Qt::AutoColor) override |
| virtual void | drawLines(const QLine *lines, int lineCount) override |
| virtual void | drawLines(const QLineF *lines, int lineCount) override |
| virtual void | drawPixmap(const QRectF &r, const QPixmap &pixmap, const QRectF &sr) override |
| virtual void | drawPoints(const QPointF *points, int pointCount) override |
| virtual void | drawPolygon(const QPointF *points, int pointCount, QPaintEngine::PolygonDrawMode mode) override |
| virtual void | drawPolygon(const QPoint *points, int pointCount, QPaintEngine::PolygonDrawMode mode) override |
| virtual void | drawRects(const QRect *rects, int rectCount) override |
| virtual void | drawRects(const QRectF *rects, int rectCount) override |
| virtual void | drawStaticTextItem(QStaticTextItem *textItem) override |
| virtual void | drawTextItem(const QPointF &p, const QTextItem &textItem) override |
| virtual void | drawTiledPixmap(const QRectF &r, const QPixmap &pixmap, const QPointF &sr) override |
| virtual bool | end() override |
| virtual void | fillRect(const QRectF &r, const QBrush &brush) override |
| virtual void | fillRect(const QRectF &r, const QColor &color) override |
| virtual bool | shouldDrawCachedGlyphs(QFontEngine *fontEngine, const QTransform &m) const override |
Related Non-Members
Detailed Description
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 and a custom window surface 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 also 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.
[virtual] QRasterPaintEngine::~QRasterPaintEngine()
Destroys this paint engine.
[override virtual] bool QRasterPaintEngine::begin(QPaintDevice *device)
Reimplements: QPaintEngine::begin(QPaintDevice *pdev).
[override virtual] void QRasterPaintEngine::drawEllipse(const QRectF &rect)
Reimplements: QPaintEngine::drawEllipse(const QRectF &rect).
[override virtual] void QRasterPaintEngine::drawImage(const QRectF &r, const QImage &img, const QRectF &sr, Qt::ImageConversionFlags flags = Qt::AutoColor)
Reimplements: QPaintEngine::drawImage(const QRectF &rectangle, const QImage &image, const QRectF &sr, Qt::ImageConversionFlags flags).
[override virtual] void QRasterPaintEngine::drawLines(const QLine *lines, int lineCount)
Reimplements: QPaintEngine::drawLines(const QLine *lines, int lineCount).
[override virtual] void QRasterPaintEngine::drawLines(const QLineF *lines, int lineCount)
Reimplements: QPaintEngine::drawLines(const QLineF *lines, int lineCount).
[override virtual] void QRasterPaintEngine::drawPixmap(const QRectF &r, const QPixmap &pixmap, const QRectF &sr)
Reimplements: QPaintEngine::drawPixmap(const QRectF &r, const QPixmap &pm, const QRectF &sr).
[override virtual] void QRasterPaintEngine::drawPoints(const QPointF *points, int pointCount)
Reimplements: QPaintEngine::drawPoints(const QPointF *points, int pointCount).
[override virtual] void QRasterPaintEngine::drawPolygon(const QPointF *points, int pointCount, QPaintEngine::PolygonDrawMode mode)
Reimplements: QPaintEngine::drawPolygon(const QPointF *points, int pointCount, QPaintEngine::PolygonDrawMode mode).
[override virtual] void QRasterPaintEngine::drawPolygon(const QPoint *points, int pointCount, QPaintEngine::PolygonDrawMode mode)
Reimplements: QPaintEngine::drawPolygon(const QPoint *points, int pointCount, QPaintEngine::PolygonDrawMode mode).
[override virtual] void QRasterPaintEngine::drawRects(const QRect *rects, int rectCount)
Reimplements: QPaintEngine::drawRects(const QRect *rects, int rectCount).
[override virtual] void QRasterPaintEngine::drawRects(const QRectF *rects, int rectCount)
Reimplements: QPaintEngine::drawRects(const QRectF *rects, int rectCount).
[override virtual] void QRasterPaintEngine::drawStaticTextItem(QStaticTextItem *textItem)
[override virtual] void QRasterPaintEngine::drawTextItem(const QPointF &p, const QTextItem &textItem)
Reimplements: QPaintEngine::drawTextItem(const QPointF &p, const QTextItem &textItem).
[override virtual] void QRasterPaintEngine::drawTiledPixmap(const QRectF &r, const QPixmap &pixmap, const QPointF &sr)
Reimplements: QPaintEngine::drawTiledPixmap(const QRectF &rect, const QPixmap &pixmap, const QPointF &p).
[override virtual] bool QRasterPaintEngine::end()
Reimplements: QPaintEngine::end().
[override virtual] void QRasterPaintEngine::fillRect(const QRectF &r, const QBrush &brush)
[override virtual] void QRasterPaintEngine::fillRect(const QRectF &r, const QColor &color)
[override virtual] bool QRasterPaintEngine::shouldDrawCachedGlyphs(QFontEngine *fontEngine, const QTransform &m) const
Returns whether glyph caching is supported by the font engine fontEngine with the given transform m applied.
Related Non-Members
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).