source: trunk/doc/src/wince-opengl.qdoc@ 551

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/*!
    \page windowsce-opengl.html
    \title Windows CE OpenGL ES
    \ingroup qtce
    \brief Information about support for OpenGL ES with Qt for Windows CE.

    \section1 Introduction

    \l {http://www.opengl.org}{OpenGL} is an industry standard API for 2D/3D
    graphics. It provides a powerful, low-level interface between software
    and acceleration hardware, and it is operating system and window system
    independent.

    \l {http://www.khronos.org/opengles}{OpenGL ES} is a subset of the
    \l {http://www.opengl.org}{OpenGL} standard. It is meant for use in
    embedded systems. Hence, it has a smaller, more constrained API.

    Qt for Windows CE uses EGL 1.1 to embed OpenGL ES windows within the
    Windows CE window manager.

    To use OpenGL ES enabled widgets in a Qt for Windows CE application, you
    only need to subclass QGLWidget and draw on instances of the subclass with
    OpenGL ES functions.

    OpenGL ES includes profiles for floating-point and fixed-point arithmetic.
    The floating point profile is called OpenGL ES CM (Common) and the
    fixed-point profile is called OpenGL ES CL (Common Lite).

    You can run \c{configure} with the \c{-opengl-es-cm} option for the Common
    profile or \c{-opengl-es-cl} for the Common Lite profile. In both cases,
    ensure that the \c{lib} and \c{includes} paths include the OpenGL ES
    headers and libararies from your SDK. The OpenGL ES lib should be called
    either \c{libGLES_CM.lib} for the Common profile or \c{libGLES_CL.lib}
    for the Common Lite profile.

    To configure Qt for Windows Mobile 5.0 and OpenGL ES Common Lite support
    you can run \c{configure} like this:

    \snippet doc/src/snippets/code/doc_src_wince-opengl.qdoc 0

    The distinction between the Common and Common Lite profiles is important,
    because the Common Lite profile has less functionality and only supports a
    fixed-point vertex format.

    To start programming with Qt and OpenGL ES on Windows CE, you can start
    with the \l{Hello GL ES Example}. This example shows how to use QGLWidget
    and QGLPainter with OpenGL ES. It also provides some hints on how to port
    OpenGL code to OpenGL ES.

    \section2 Using OpenGL to Accelerate Normal 2D Painting

    Qt provides QOpenGLPaintEngine, a subclass of QPaintEngine that translates
    QPainter operations into OpenGL calls. This is especially convenient for
    drawing text or QImage objects in an OpenGL ES context. For further
    details, refer to the \l{Hello GL ES Example}.

*/