source: trunk/src/gui/image/qiconengine.cpp@ 260

/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Qt Software Information ([email protected])
**
** This file is part of the QtGui module 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 [email protected].
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qiconengine.h"
#include "qpainter.h"

QT_BEGIN_NAMESPACE

/*!
  \class QIconEngine

  \brief The QIconEngine class provides an abstract base class for QIcon renderers.

  \ingroup multimedia

  \bold {Use QIconEngineV2 instead.}

  An icon engine provides the rendering functions for a QIcon. Each icon has a
  corresponding icon engine that is responsible for drawing the icon with a
  requested size, mode and state.

  The icon is rendered by the paint() function, and the icon can additionally be
  obtained as a pixmap with the pixmap() function (the default implementation
  simply uses paint() to achieve this). The addPixmap() function can be used to
  add new pixmaps to the icon engine, and is used by QIcon to add specialized
  custom pixmaps.

  The paint(), pixmap(), and addPixmap() functions are all virtual, and can
  therefore be reimplemented in subclasses of QIconEngine.

  \sa QIconEngineV2, QIconEnginePlugin

*/

/*!
  \fn virtual void QIconEngine::paint(QPainter *painter, const QRect &rect, QIcon::Mode mode, QIcon::State state) = 0;

  Uses the given \a painter to paint the icon with the required \a mode and
  \a state into the rectangle \a rect.
*/

/*!  Returns the actual size of the icon the engine provides for the
  requested \a size, \a mode and \a state. The default implementation
  returns the given \a size.
 */
QSize QIconEngine::actualSize(const QSize &size, QIcon::Mode /*mode*/, QIcon::State /*state*/)
{
    return size;
}


/*!
  Destroys the icon engine.
 */
QIconEngine::~QIconEngine()
{
}


/*!
  Returns the icon as a pixmap with the required \a size, \a mode,
  and \a state. The default implementation creates a new pixmap and
  calls paint() to fill it.
*/
QPixmap QIconEngine::pixmap(const QSize &size, QIcon::Mode mode, QIcon::State state)
{
    QPixmap pm(size);
    {
        QPainter p(&pm);
        paint(&p, QRect(QPoint(0,0),size), mode, state);
    }
    return pm;
}

/*!
  Called by QIcon::addPixmap(). Adds a specialized \a pixmap for the given
  \a mode and \a state. The default pixmap-based engine stores any supplied
  pixmaps, and it uses them instead of scaled pixmaps if the size of a pixmap
  matches the size of icon requested. Custom icon engines that implement
  scalable vector formats are free to ignores any extra pixmaps.
 */
void QIconEngine::addPixmap(const QPixmap &/*pixmap*/, QIcon::Mode /*mode*/, QIcon::State /*state*/)
{
}


/*!  Called by QIcon::addFile(). Adds a specialized pixmap from the
  file with the given \a fileName, \a size, \a mode and \a state. The
  default pixmap-based engine stores any supplied file names, and it
  loads the pixmaps on demand instead of using scaled pixmaps if the
  size of a pixmap matches the size of icon requested. Custom icon
  engines that implement scalable vector formats are free to ignores
  any extra files.
 */
void QIconEngine::addFile(const QString &/*fileName*/, const QSize &/*size*/, QIcon::Mode /*mode*/, QIcon::State /*state*/)
{
}



// version 2 functions


/*!
    \class QIconEngineV2

    \brief The QIconEngineV2 class provides an abstract base class for QIcon renderers.

    \ingroup multimedia
    \since 4.3

    An icon engine renders \l{QIcon}s. With icon engines, you can
    customize icons. Qt provides a default engine that makes icons
    adhere to the current style by scaling the icons and providing a
    disabled appearance.

    An engine is installed on an icon either through a QIcon
    constructor or through a QIconEnginePluginV2. The plugins are used
    by Qt if a specific engine is not given when the icon is created.
    See the QIconEngineV2 class description to learn how to create
    icon engine plugins.

    An icon engine provides the rendering functions for a QIcon. Each
    icon has a corresponding icon engine that is responsible for drawing
    the icon with a requested size, mode and state.

    QIconEngineV2 extends the API of QIconEngine to allow streaming of
    the icon engine contents, and should be used instead of QIconEngine
    for implementing new icon engines.

    \sa QIconEnginePluginV2

*/

/*!
    \enum QIconEngineV2::IconEngineHook
    \since 4.5