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+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Free Documentation License
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of this
+** file.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+    \group painting
+    \title Painting Classes
+    \ingroup groups
+
+    \brief Classes that provide support for painting.
+
+    See also this introduction to the \link coordsys.html Qt
+    coordinate system. \endlink
+*/
+
+/*!
+    \group painting-3D
+    \title Rendering in 3D
+    \ingroup groups
+
+    \brief Classes that provide support for rendering in 3D.
+*/
+
+/*!
+    \page paintsystem.html
+    \title Paint System
+    \brief A system for painting on the screen or on print devices using the same API
+    \ingroup qt-graphics
+    \ingroup frameworks-technologies
+    \ingroup qt-basic-concepts
+	
+
+    Qt's paint system enables painting on screen and print devices
+    using the same API, and is primarily based on the QPainter,
+    QPaintDevice, and QPaintEngine classes.
+
+    QPainter is used to perform drawing operations, QPaintDevice is an
+    abstraction of a two-dimensional space that can be painted on
+    using a QPainter, and QPaintEngine provides the interface that the
+    painter uses to draw onto different types of devices. The
+    QPaintEngine class is used internally by QPainter and
+    QPaintDevice, and is hidden from application programmers unless
+    they create their own device type.
+
+    \image paintsystem-core.png
+
+    The main benefit of this approach is that all painting follows the
+    same painting pipeline making it easy to add support for new
+    features and providing default implementations for unsupported
+    ones.
+    
+    \section1 Topics
+    \list
+        \o \l{Classes for Painting}
+        \o \l{Paint Devices and Backends}
+        \o \l{Drawing and Filling}
+        \o \l{Coordinate System}
+        \o \l{Reading and Writing Image Files}
+        \o \l{Styling}
+        \o \l{Printing with Qt}
+    \endlist
+
+    \section1 Classes for Painting
+
+    These classes provide support for painting onto a paint device.
+
+    \annotatedlist painting
+
+    Alternatively, Qt provides the QtOpenGL module, offering classes
+    that makes it easy to use OpenGL in Qt applications. Among others,
+    the module provides an OpenGL widget class that can be used just
+    like any other Qt widget, except that it opens an OpenGL display
+    buffer where the OpenGL API can be used to render the contents.
+*/
+
+
+/*!
+    \page paintsystem-devices.html
+    \title Paint Devices and Backends
+
+	\contentspage The Paint System
+	\nextpage Drawing and Filling
+
+    \section1 Creating a Paint Device
+
+    The QPaintDevice class is the base class of objects that can be
+    painted, i.e. QPainter can draw on any QPaintDevice
+    subclass. QPaintDevice's drawing capabilities are currently
+    implemented by the QWidget, QImage, QPixmap, QGLWidget,
+    QGLPixelBuffer, QPicture and QPrinter subclasses.
+
+    \image paintsystem-devices.png
+
+    \table 100%
+    \row \o \bold Widget
+
+    The QWidget class is the base class of all user interface
+    objects. The widget is the atom of the user interface: it receives
+    mouse, keyboard and other events from the window system, and
+    paints a representation of itself on the screen.
+
+    \row \o \bold Image
+
+    The QImage class provides a hardware-independent image
+    representation which is designed and optimized for I/O, and for
+    direct pixel access and manipulation. QImage supports several
+    image formats including monochrome, 8-bit, 32-bit and
+    alpha-blended images.
+
+    One advantage of using QImage as a paint device is that it is
+    possible to guarantee the pixel exactness of any drawing operation
+    in a platform-independent way. Another benefit is that the
+    painting can be performed in another thread than the current GUI
+    thread.
+    
+    \row \o \bold Pixmap
+
+    The QPixmap class is an off-screen image representation which is
+    designed and optimized for showing images on screen. Unlike
+    QImage, the pixel data in a pixmap is internal and is managed by
+    the underlying window system, i.e. pixels can only be accessed
+    through QPainter functions or by converting the QPixmap to a
+    QImage.
+
+    To optimize drawing with QPixmap, Qt provides the QPixmapCache
+    class which can be used to store temporary pixmaps that are
+    expensive to generate without using more storage space than the
+    cache limit.
+
+    Qt also provides the QBitmap convenience class, inheriting
+    QPixmap. QBitmap guarantees monochrome (1-bit depth) pixmaps, and
+    is mainly used for creating custom QCursor and QBrush objects,
+    constructing QRegion objects, and for setting masks for pixmaps
+    and widgets.
+
+    \row \o \bold {OpenGL Widget}
+
+    As mentioned previously, Qt provides the QtOpenGL module offering
+    classes that makes it easy to use OpenGL in Qt applications. For
+    example, the QGLWidget enables the OpenGL API for
+    rendering.
+
+    But QGLWidget is also a QWidget subclass, and can be used by
+    QPainter as any other paint device. One huge benefit from this is
+    that it enables Qt to utilize the high performance of OpenGL for
+    most drawing operations, such as transformations and pixmap
+    drawing.
+
+    \row \o \bold {Pixel Buffer}
+
+    The QtOpenGL module also provides the QGLPixelBuffer class which
+    inherits QPaintDevice directly.
+
+    QGLPixelBuffer encapsulates an OpenGL pbuffer. Rendering into a
+    pbuffer is normally done using full hardware acceleration which
+    can be significantly faster than rendering into a QPixmap.
+
+    \row \o \bold {Framebuffer Object}
+
+    The QtOpenGL module also provides the QGLFramebufferObject class
+    which inherits QPaintDevice directly.
+
+    QGLFramebufferObject encapsulates an OpenGL framebuffer object.
+    Framebuffer objects can also be used for off-screen rendering, and
+    offer several advantages over pixel buffers for this purpose.
+    These are described in the QGLFramebufferObject class documentation.
+
+    \row \o \bold {Picture}
+
+    The QPicture class is a paint device that records and replays
+    QPainter commands. A picture serializes painter commands to an IO
+    device in a platform-independent format. QPicture is also
+    resolution independent, i.e. a QPicture can be displayed on
+    different devices (for example svg, pdf, ps, printer and screen)
+    looking the same.
+
+    Qt provides the QPicture::load() and QPicture::save() functions
+    as well as streaming operators for loading and saving pictures.
+
+    \row \o \bold {Printer}
+
+    The QPrinter class is a paint device that paints on a printer. On
+    Windows or Mac OS X, QPrinter uses the built-in printer
+    drivers. On X11, QPrinter generates postscript and sends that to
+    lpr, lp, or another print program. QPrinter can also print to any
+    other QPrintEngine object.
+
+    The QPrintEngine class defines an interface for how QPrinter
+    interacts with a given printing subsystem. The common case when
+    creating your own print engine, is to derive from both
+    QPaintEngine and QPrintEngine.
+
+    The output format is by default determined by the platform the
+    printer is running on, but by explicitly setting the output format
+    to QPrinter::PdfFormat, QPrinter will generate its output as a PDF
+    file.
+
+    \row \o \bold {Custom Backends}
+
+    Support for a new backend can be implemented by deriving from the
+    QPaintDevice class and reimplementing the virtual
+    QPaintDevice::paintEngine() function to tell QPainter which paint
+    engine should be used to draw on this particular device. To
+    actually be able to draw on the device, this paint engine must be
+    a custom paint engine created by deriving from the QPaintEngine
+    class.
+    
+    \endtable
+
+    \section1 Selecting the Painting Backend
+
+    Since Qt 4.5, it is possible to replace the paint engines and paint
+    devices used for widgets, pixmaps and the offscreen double buffer. By
+    default the backends are:
+
+    \table
+        \row
+            \o Windows
+            \o Software Rasterizer
+        \row
+            \o X11
+            \o X11
+        \row
+            \o Mac OS X
+            \o CoreGraphics
+        \row
+            \o Embedded
+            \o Software Rasterizer
+    \endtable
+
+    Passing a command line parameter to the application, such as,
+    \c{-graphicssystem raster}, specifies that Qt should use the software
+    rasterizer for this application. The Software rasterizer is fully
+    supported on all platforms.
+
+    \code
+      > analogclock -graphicssystem raster
+    \endcode
+
+    There is also a \c{-graphicssystem opengl} mode that uses OpenGL for
+    all drawing. Currently, this engine is experimental as it does not draw
+    everything correctly.
+
+    Qt also supports being configured using \c {-graphicssystem
+    raster|opengl} in which case all applications will use the
+    specified graphics system for its graphics.
+*/
+
+/*!
+    \page paintsystem-drawing.html
+    \title Drawing and Filling
+    
+    \previouspage Paint Devices and Backends
+    \contentspage The Paint System
+    \nextpage Coordinate System
+
+    \section1 Drawing
+
+    QPainter provides highly optimized functions to do most of the
+    drawing GUI programs require. It can draw everything from simple
+    graphical primitives (represented by the QPoint, QLine, QRect,
+    QRegion and QPolygon classes) to complex shapes like vector
+    paths. In Qt vector paths are represented by the QPainterPath
+    class. QPainterPath provides a container for painting operations,
+    enabling graphical shapes to be constructed and reused.
+
+    \table 100%
+    \row
+    \o \image paintsystem-painterpath.png
+    \o \bold QPainterPath
+
+    A painter path is an object composed of lines and curves. For
+    example, a rectangle is composed by lines and an ellipse is
+    composed by curves.
+
+    The main advantage of painter paths over normal drawing operations
+    is that complex shapes only need to be created once; then they can
+    be drawn many times using only calls to the QPainter::drawPath()
+    function.
+
+    A QPainterPath object can be used for filling, outlining, and
+    clipping. To generate fillable outlines for a given painter path,
+    use the QPainterPathStroker class.
+
+    \endtable
+
+    Lines and outlines are drawn using the QPen class. A pen is
+    defined by its style (i.e. its line-type), width, brush, how the
+    endpoints are drawn (cap-style) and how joins between two
+    connected lines are drawn (join-style). The pen's brush is a
+    QBrush object used to fill strokes generated with the pen,
+    i.e. the QBrush class defines the fill pattern.
+
+    QPainter can also draw aligned text and pixmaps.
+
+    When drawing text, the font is specified using the QFont class. Qt
+    will use the font with the specified attributes, or if no matching
+    font exists, Qt will use the closest matching installed font. The
+    attributes of the font that is actually used can be retrieved
+    using the QFontInfo class. In addition, the QFontMetrics class
+    provides the font measurements, and the QFontDatabase class
+    provides information about the fonts available in the underlying
+    window system.
+
+    Normally, QPainter draws in a "natural" coordinate system, but it
+    is able to perform view and world transformations using the
+    QTransform class. For more information, see \l {Coordinate
+    System}, which also describes the rendering process, i.e. the
+    relation between the logical representation and the rendered
+    pixels, and the benefits of anti-aliased painting.
+
+    \table 100%
+    \row \o
+    \bold {Anti-Aliased Painting}
+
+    When drawing, the pixel rendering is controlled by the
+    QPainter::Antialiasing render hint. The QPainter::RenderHint enum
+    is used to specify flags to QPainter that may or may not be
+    respected by any given engine.
+
+    The QPainter::Antialiasing value indicates that the engine should
+    antialias edges of primitives if possible, i.e. smoothing the
+    edges by using different color intensities.
+
+    \o \image paintsystem-antialiasing.png
+
+    \endtable
+
+    \section1 Filling
+
+    Shapes are filled using the QBrush class. A brush is defined
+    by its color and its style (i.e. its fill pattern).
+
+    Any color in Qt is represented by the QColor class which supports
+    the RGB, HSV and CMYK color models. QColor also support
+    alpha-blended outlining and filling (specifying the transparency
+    effect), and the class is platform and device independent (the
+    colors are mapped to hardware using the QColormap class). For more
+    information, see the QColor class documentation.
+
+    When creating a new widget, it is recommend to use the colors in
+    the widget's palette rather than hard-coding specific colors. All
+    widgets in Qt contain a palette and use their palette to draw
+    themselves. A widget's palette is represented by the QPalette
+    class which contains color groups for each widget state.
+
+    The available fill patterns are described by the Qt::BrushStyle
+    enum. These include basic patterns spanning from uniform color to
+    very sparse pattern, various line combinations, gradient fills and
+    textures. Qt provides the QGradient class to define custom
+    gradient fills, while texture patterns are specified using the
+    QPixmap class.
+
+    \table 100%
+    \row
+    \o \image paintsystem-fancygradient.png
+    \o \bold QGradient
+
+    The QGradient class is used in combination with QBrush to specify
+    gradient fills.
+
+    \image paintsystem-gradients.png
+
+    Qt currently supports three types of gradient fills: Linear
+    gradients interpolate colors between start and end points, radial
+    gradients interpolate colors between a focal point and end points
+    on a circle surrounding it, and conical gradients interpolate
+    colors around a center point.
+
+    \endtable
+*/
+
+/*!
+    \page paintsystem-images.html
+    \title Reading and Writing Image Files
+
+    \previouspage Coordinate System
+    \contentspage The Paint System
+    \nextpage Styling
+
+    The most common way to read images is through QImage and QPixmap's
+    constructors, or by calling the QImage::load() and QPixmap::load()
+    functions. In addition, Qt provides the QImageReader class which
+    gives more control over the process. Depending on the underlying
+    support in the image format, the functions provided by the class
+    can save memory and speed up loading of images.
+
+    Likewise, Qt provides the QImageWriter class which supports
+    setting format specific options, such as the gamma level,
+    compression level and quality, prior to storing the image. If you
+    do not need such options, you can use QImage::save() or
+    QPixmap::save() instead.
+
+    \table 100%
+    \row
+    \o \bold QMovie
+
+    QMovie is a convenience class for displaying animations, using the
+    QImageReader class internally.  Once created, the QMovie class
+    provides various functions for both running and controlling the
+    given animation.
+
+    \o \image paintsystem-movie.png
+    \endtable
+
+    The QImageReader and QImageWriter classes rely on the
+    QImageIOHandler class which is the common image I/O interface for
+    all image formats in Qt. QImageIOHandler objects are used
+    internally by QImageReader and QImageWriter to add support for
+    different image formats to Qt.
+
+    A list of the supported file formats are available through the
+    QImageReader::supportedImageFormats() and
+    QImageWriter::supportedImageFormats() functions. Qt supports
+    several file formats by default, and in addition new formats can
+    be added as plugins. The currently supported formats are listed in
+    the QImageReader and QImageWriter class documentation.
+
+    Qt's plugin mechanism can also be used to write a custom image
+    format handler. This is done by deriving from the QImageIOHandler
+    class, and creating a QImageIOPlugin object which is a factory for
+    creating QImageIOHandler objects. When the plugin is installed,
+    QImageReader and QImageWriter will automatically load the plugin
+    and start using it.
+
+    \section1 Rendering SVG files
+
+    \table 100%
+    \row
+    \o \image paintsystem-svg.png
+    \o \bold {SVG Rendering}
+
+	Scalable Vector Graphics (SVG) is a language for describing two-dimensional
+	graphics and graphical applications in XML. SVG 1.1 is a W3C Recommendation
+	and forms the core of the current SVG developments in Qt. SVG 1.2 is the
+	specification currently being developed by the \l{SVG Working Group}, and it
+	is \l{http://www.w3.org/TR/SVG12/}{available in draft form}.
+	The \l{Mobile SVG Profiles} (SVG Basic and SVG Tiny) are aimed at
+	resource-limited devices and are part of the 3GPP platform for third generation
+	mobile phones. You can read more about SVG at \l{About SVG}.
+
+	Qt supports the \l{SVG 1.2 Tiny Static Features}{static features} of
+	\l{SVG 1.2 Tiny}. ECMA scripts and DOM manipulation are currently not
+	supported.
+
+    SVG drawings can be rendered onto any QPaintDevice subclass. This
+    approach gives developers the flexibility to experiment, in order
+    to find the best solution for each application.
+
+	The easiest way to render SVG files is to construct a QSvgWidget and
+	load an SVG file using one of the QSvgWidget::load() functions.
+
+	QSvgRenderer is the class responsible for rendering SVG files for
+	QSvgWidget, and it can be used directly to provide SVG support for
+	custom widgets.
+	To load an SVG file, construct a QSvgRenderer with a file name or the
+	contents of a file, or call QSvgRenderer::load() on an existing
+	renderer. If the SVG file has been loaded successfully the
+	QSvgRenderer::isValid() will return true.
+
+	Once you have loaded the SVG file successfully, you can render it
+	with the QSvgRenderer::render() function. Note that this scheme allows
+	you to render SVG files on all paint devices supported by Qt, including
+	QWidget, QGLWidget, and QImage. See the \l{SVG Viewer Example}{SVG Viewer}
+	example for more details.
+
+    \endtable
+*/
+
+/*!
+    \page paintsystem-styling.html
+    \title Styling
+
+    \previouspage Reading and Writing Image Files
+    \contentspage The Paint System
+    \nextpage Printing with Qt
+
+    Qt's built-in widgets use the QStyle class to perform nearly all
+    of their drawing.  QStyle is an abstract base class that
+    encapsulates the look and feel of a GUI, and can be used to make
+    the widgets look exactly like the equivalent native widgets or to
+    give the widgets a custom look.
+
+    Qt provides a set of QStyle subclasses that emulate the native
+    look of the different platforms supported by Qt (QWindowsStyle,
+    QMacStyle, QMotifStyle, etc.). These styles are built into the
+    QtGui library, other styles can be made available using Qt's
+    plugin mechansim.
+
+    Most functions for drawing style elements take four arguments:
+
+    \list
+    \o an enum value specifying which graphical element to draw
+    \o a QStyleOption object specifying how and where to render that element
+    \o a QPainter object that should be used to draw the element
+    \o a QWidget object on which the drawing is performed (optional)
+    \endlist
+
+    The style gets all the information it needs to render the
+    graphical element from the QStyleOption class. The widget is
+    passed as the last argument in case the style needs it to perform
+    special effects (such as animated default buttons on Mac OS X),
+    but it isn't mandatory. In fact, QStyle can be used to draw on any
+    paint device (not just widgets), in which case the widget argument
+    is a zero pointer.
+
+    \image paintsystem-stylepainter.png
+
+    The paint system also provides the QStylePainter class inheriting
+    from QPainter.  QStylePainter is a convenience class for drawing
+    QStyle elements inside a widget, and extends QPainter with a set
+    of high-level drawing functions implemented on top of QStyle's
+    API. The advantage of using QStylePainter is that the parameter
+    lists get considerably shorter.
+
+    \table 100%
+    \row
+    \o \inlineimage paintsystem-icon.png
+    \o \bold QIcon
+
+    The QIcon class provides scalable icons in different modes and states.
+
+    QIcon can generate pixmaps reflecting an icon's state, mode and
+    size. These pixmaps are generated from the set of pixmaps
+    made available to the icon, and are used by Qt widgets to show an
+    icon representing a particular action.
+
+    The rendering of a QIcon object is handled by the QIconEngine
+    class. Each icon has a corresponding icon engine that is
+    responsible for drawing the icon with a requested size, mode and
+    state.
+
+    \endtable
+    
+    For more information about widget styling and appearance, see the
+    \l{Styles and Style Aware Widgets}.
+*/