内容

• 公共函数
• 重实现公共函数
• 相关非成员
• 详细描述

QRasterPaintEngine 类

QRasterPaintEngine 类启用描绘操作硬件加速 (在 Qt for Embedded Linux 中)。 更多...

头：	#include <QRasterPaintEngine>
qmake:	QT += gui
Since:	Qt 4.2
继承：	QPaintEngineEx

该类在开发且可能改变。

该类在 Qt 4.2 引入。

• 所有成员列表，包括继承成员

公共函数

	QRasterPaintEngine (QPaintDevice * device )
virtual	~QRasterPaintEngine ()

重实现公共函数

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

相关非成员

typedef

QSpan

详细描述

注意：此功能仅用于 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.

注意： 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 .

另请参阅 QPaintEngine .

成员函数文档编制

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 .

该函数在 Qt 4.5 引入。

[virtual] QRasterPaintEngine:: ~QRasterPaintEngine ()

销毁此描绘引擎。

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

重实现： QPaintEngine::begin (QPaintDevice *pdev).

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

重实现： QPaintEngine::drawEllipse (const QRectF &rect).

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

重实现： QPaintEngine::drawImage (const QRectF &rectangle, const QImage &image, const QRectF &sr, Qt::ImageConversionFlags flags).

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

重实现： QPaintEngine::drawLines (const QLine *lines, int lineCount).

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

重实现： QPaintEngine::drawLines (const QLineF *lines, int lineCount).

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

重实现： QPaintEngine::drawPixmap (const QRectF &r, const QPixmap &pm, const QRectF &sr).

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

重实现： QPaintEngine::drawPoints (const QPointF *points, int pointCount).

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

重实现： QPaintEngine::drawPolygon (const QPointF *points, int pointCount, QPaintEngine::PolygonDrawMode mode).

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

重实现： QPaintEngine::drawPolygon (const QPoint *points, int pointCount, QPaintEngine::PolygonDrawMode mode).

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

重实现： QPaintEngine::drawRects (const QRect *rects, int rectCount).

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

重实现： 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 )

重实现： QPaintEngine::drawTextItem (const QPointF &p, const QTextItem &textItem).

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

重实现： QPaintEngine::drawTiledPixmap (const QRectF &rect, const QPixmap &pixmap, const QPointF &p).

[override virtual] bool QRasterPaintEngine:: end ()

重实现： 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.

相关非成员

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).