/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Qt Software Information (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain
** additional rights. These rights are described in the Nokia Qt LGPL
** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
** package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at qt-sales@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/

/*!
    \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}.

*/