source: trunk/doc/src/platforms/emb-HwAcc-LinuxEmbedded.qdoc@ 651

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/*!

    \page qt-embeddedLinux-accel.html

    \target Hardware Acceleration with Qt for Embedded Linux

    \title Qt for Embedded Linux Hardware Accelerated Graphics
    \ingroup qt-embedded-linux


        \input platforms/emb-hardwareacceleration.qdocinc

    \section1 Windowing on Embedded Linux with Hardware Accelerated Graphics

    Qt for Embedded Linux includes its own windowing system, QWS. QWS was
    designed in 1999, well before graphics acceleration was available for
    embedded devices. It does a great job providing a lightweight window
    manager including all the expected functionality such as arbitrary
    windows that can be moved, resized, minimized, etc. Getting QWS to work
    with GPUs is very challenging, particularly with OpenGL and OpenVG
    because there is no standard way in Linux to share textures across
    processes. Some silicon vendors provide private APIs to allow texture
    sharing, others do not. These limitations are documented under the
    sections describing each type of accelerated hardware APIs. The simplest
    most generic support for accelerated graphics is a full screen single
    process single window.

    \section2 General options
    \list
        \o QWS, not accelerated, allows arbitrary windowing with multiple
        processes drawing on the screen.
        \o X11 with an accelerated X11 driver provided by the silicon
        vendor. Like QWS, this allows arbitrary windows with multiple
        processes drawing on the screen. Our experience is that there is
        some overhead from X11 which will adversely affect framerates.
        Additionally, our experience is that the drivers from silicon
        vendors are still maturing.
        \o Full screen single process single window. This will always work.
        Some additional capabilities are available and are documented in
        the acceleration specific API sections.
    \endlist

    \section1 Supported Hardware Accelerated Graphics APIs

    This table shows which Hardware Accelerated Graphics APIs currently
    supported by Qt.

     \table 
     \header
        \o Supported APIs
                \o API Version
     \row
        \o \l {Qt for Embedded Linux and OpenGL}{OpenGL ES}
                \o 1.x and 2.x
     \row
        \o \l {Qt for Embedded Linux and OpenVG}{OpenVG } 
                \o 1.1
     \row
        \o \l {Qt for Embedded Linux and DirectFB}{DirectFB}
                \o 2.0
     \endtable 


*/