QRasterPaintEngine Class

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

Header: #include <QRasterPaintEngine>
qmake: QT += gui
Since: Qt 4.2
Inherits: QPaintEngineEx

This class is under development and is subject to change.

This class was introduced in Qt 4.2.

typedef QSpan

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.

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).