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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}.

*/