src/gui/image/qbitmap.cpp
changeset 0 1918ee327afb
child 3 41300fa6a67c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/gui/image/qbitmap.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,403 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 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 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qbitmap.h"
+#include "qpixmapdata_p.h"
+#include "qimage.h"
+#include "qvariant.h"
+#include <qpainter.h>
+#include <private/qgraphicssystem_p.h>
+#include <private/qapplication_p.h>
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \class QBitmap
+    \brief The QBitmap class provides monochrome (1-bit depth) pixmaps.
+
+    \ingroup painting
+    \ingroup shared
+
+    The QBitmap class is a monochrome off-screen paint device used
+    mainly for creating custom QCursor and QBrush objects,
+    constructing QRegion objects, and for setting masks for pixmaps
+    and widgets.
+
+    QBitmap is a QPixmap subclass ensuring a depth of 1, except for
+    null objects which have a depth of 0. If a pixmap with a depth
+    greater than 1 is assigned to a bitmap, the bitmap will be
+    dithered automatically.
+
+    Use the QColor objects Qt::color0 and Qt::color1 when drawing on a
+    QBitmap object (or a QPixmap object with depth 1).
+
+    Painting with Qt::color0 sets the bitmap bits to 0, and painting
+    with Qt::color1 sets the bits to 1. For a bitmap, 0-bits indicate
+    background (or transparent pixels) and 1-bits indicate foreground
+    (or opaque pixels). Use the clear() function to set all the bits
+    to Qt::color0. Note that using the Qt::black and Qt::white colors
+    make no sense because the QColor::pixel() value is not necessarily
+    0 for black and 1 for white.
+
+    The QBitmap class provides the transformed() function returning a
+    transformed copy of the bitmap; use the QTransform argument to
+    translate, scale, shear, and rotate the bitmap. In addition,
+    QBitmap provides the static fromData() function which returns a
+    bitmap constructed from the given \c uchar data, and the static
+    fromImage() function returning a converted copy of a QImage
+    object.
+
+    Just like the QPixmap class, QBitmap is optimized by the use of
+    implicit data sharing. For more information, see the {Implicit
+    Data Sharing} documentation.
+
+    \sa  QPixmap, QImage, QImageReader, QImageWriter
+*/
+
+/*! \typedef QBitmap::DataPtr
+  \internal
+ */
+
+/*!
+    Constructs a null bitmap.
+
+    \sa QPixmap::isNull()
+*/
+QBitmap::QBitmap()
+    : QPixmap(QSize(0, 0), QPixmapData::BitmapType)
+{
+}
+
+/*!
+    \fn QBitmap::QBitmap(int width, int height)
+
+    Constructs a bitmap with the given \a width and \a height. The pixels
+    inside are uninitialized.
+
+    \sa clear()
+*/
+
+QBitmap::QBitmap(int w, int h)
+    : QPixmap(QSize(w, h), QPixmapData::BitmapType)
+{
+}
+
+/*!
+    Constructs a bitmap with the given \a size.  The pixels in the
+    bitmap are uninitialized.
+
+    \sa clear()
+*/
+
+QBitmap::QBitmap(const QSize &size)
+    : QPixmap(size, QPixmapData::BitmapType)
+{
+}
+
+/*!
+    \fn QBitmap::clear()
+
+    Clears the bitmap, setting all its bits to Qt::color0.
+*/
+
+/*!
+    Constructs a bitmap that is a copy of the given \a pixmap.
+
+    If the pixmap has a depth greater than 1, the resulting bitmap
+    will be dithered automatically.
+
+    \sa QPixmap::depth(), fromImage(), fromData()
+*/
+
+QBitmap::QBitmap(const QPixmap &pixmap)
+{
+    QBitmap::operator=(pixmap);
+}
+
+/*!
+    \fn QBitmap::QBitmap(const QImage &image)
+
+    Constructs a bitmap that is a copy of the given \a image.
+
+    Use the static fromImage() function instead.
+*/
+
+/*!
+    Constructs a bitmap from the file specified by the given \a
+    fileName. If the file does not exist, or has an unknown format,
+    the bitmap becomes a null bitmap.
+
+    The \a fileName and \a format parameters are passed on to the
+    QPixmap::load() function. If the file format uses more than 1 bit
+    per pixel, the resulting bitmap will be dithered automatically.
+
+    \sa QPixmap::isNull(), QImageReader::imageFormat()
+*/
+
+QBitmap::QBitmap(const QString& fileName, const char *format)
+    : QPixmap(QSize(0, 0), QPixmapData::BitmapType)
+{
+    load(fileName, format, Qt::MonoOnly);
+}
+
+/*!
+    \overload
+
+    Assigns the given \a pixmap to this bitmap and returns a reference
+    to this bitmap.
+
+    If the pixmap has a depth greater than 1, the resulting bitmap
+    will be dithered automatically.
+
+    \sa QPixmap::depth()
+ */
+
+QBitmap &QBitmap::operator=(const QPixmap &pixmap)
+{
+    if (pixmap.isNull()) {                        // a null pixmap
+        QBitmap bm(0, 0);
+        QBitmap::operator=(bm);
+    } else if (pixmap.depth() == 1) {                // 1-bit pixmap
+        QPixmap::operator=(pixmap);                // shallow assignment
+    } else {                                        // n-bit depth pixmap
+        QImage image;
+        image = pixmap.toImage();                                // convert pixmap to image
+        *this = fromImage(image);                                // will dither image
+    }
+    return *this;
+}
+
+
+#ifdef QT3_SUPPORT
+QBitmap::QBitmap(int w, int h, const uchar *bits, bool isXbitmap)
+{
+    *this = fromData(QSize(w, h), bits, isXbitmap ? QImage::Format_MonoLSB : QImage::Format_Mono);
+}
+
+
+QBitmap::QBitmap(const QSize &size, const uchar *bits, bool isXbitmap)
+{
+    *this = fromData(size, bits, isXbitmap ? QImage::Format_MonoLSB : QImage::Format_Mono);
+}
+#endif
+
+/*!
+  Destroys the bitmap.
+*/
+QBitmap::~QBitmap()
+{
+}
+
+/*!
+   Returns the bitmap as a QVariant.
+*/
+QBitmap::operator QVariant() const
+{
+    return QVariant(QVariant::Bitmap, this);
+}
+
+/*!
+    \fn QBitmap &QBitmap::operator=(const QImage &image)
+    \overload
+
+    Converts the given \a image to a bitmap, and assigns the result to
+    this bitmap. Returns a reference to the bitmap.
+
+    Use the static fromImage() function instead.
+*/
+
+/*!
+    Returns a copy of the given \a image converted to a bitmap using
+    the specified image conversion \a flags.
+
+    \sa fromData()
+*/
+QBitmap QBitmap::fromImage(const QImage &image, Qt::ImageConversionFlags flags)
+{
+    if (image.isNull())
+        return QBitmap();
+
+    QImage img = image.convertToFormat(QImage::Format_MonoLSB, flags);
+
+    // make sure image.color(0) == Qt::color0 (white)
+    // and image.color(1) == Qt::color1 (black)
+    const QRgb c0 = QColor(Qt::black).rgb();
+    const QRgb c1 = QColor(Qt::white).rgb();
+    if (img.color(0) == c0 && img.color(1) == c1) {
+        img.invertPixels();
+        img.setColor(0, c1);
+        img.setColor(1, c0);
+    }
+
+    QGraphicsSystem* gs = QApplicationPrivate::graphicsSystem();
+    QScopedPointer<QPixmapData> data(gs ? gs->createPixmapData(QPixmapData::BitmapType)
+                : QGraphicsSystem::createDefaultPixmapData(QPixmapData::BitmapType));
+
+    data->fromImage(img, flags | Qt::MonoOnly);
+    return QPixmap(data.take());
+}
+
+/*!
+    Constructs a bitmap with the given \a size, and sets the contents to
+    the \a bits supplied.
+
+    The bitmap data has to be byte aligned and provided in in the bit
+    order specified by \a monoFormat. The mono format must be either
+    QImage::Format_Mono or QImage::Format_MonoLSB. Use
+    QImage::Format_Mono to specify data on the XBM format.
+
+    \sa fromImage()
+
+*/
+QBitmap QBitmap::fromData(const QSize &size, const uchar *bits, QImage::Format monoFormat)
+{
+    Q_ASSERT(monoFormat == QImage::Format_Mono || monoFormat == QImage::Format_MonoLSB);
+
+    QImage image(size, monoFormat);
+    image.setColor(0, QColor(Qt::color0).rgb());
+    image.setColor(1, QColor(Qt::color1).rgb());
+
+    // Need to memcpy each line separatly since QImage is 32bit aligned and
+    // this data is only byte aligned...
+    int bytesPerLine = (size.width() + 7) / 8;
+    for (int y = 0; y < size.height(); ++y)
+        memcpy(image.scanLine(y), bits + bytesPerLine * y, bytesPerLine);
+    return QBitmap::fromImage(image);
+}
+
+/*!
+    Returns a copy of this bitmap, transformed according to the given
+    \a matrix.
+
+    \sa QPixmap::transformed()
+ */
+QBitmap QBitmap::transformed(const QTransform &matrix) const
+{
+    QBitmap bm = QPixmap::transformed(matrix);
+    return bm;
+}
+
+/*!
+  \overload
+  \obsolete
+
+  This convenience function converts the \a matrix to a QTransform
+  and calls the overloaded function.
+*/
+QBitmap QBitmap::transformed(const QMatrix &matrix) const
+{
+    return transformed(QTransform(matrix));
+}
+
+#ifdef QT3_SUPPORT
+/*!
+    \fn QBitmap QBitmap::xForm(const QMatrix &matrix) const
+
+    Returns a copy of this bitmap, transformed according to the given
+    \a matrix.
+
+    Use transformed() instead.
+*/
+
+/*!
+    \fn QBitmap::QBitmap(const QSize &size, bool clear)
+
+    Constructs a bitmap with the given \a size. If \a clear is true,
+    the bits are initialized to Qt::color0.
+
+    Use the corresponding QBitmap() constructor instead, and then call
+    the clear() function if the \a clear parameter is true.
+*/
+
+/*!
+    \fn QBitmap::QBitmap(int width, int height, bool clear)
+
+    Constructs a bitmap with the given \a width and \a height.  If \a
+    clear is true, the bits are initialized to Qt::color0.
+
+    Use the corresponding QBitmap() constructor instead, and then call
+    the clear() function if the \a clear parameter is true.
+*/
+
+/*!
+    \fn QBitmap::QBitmap(int width, int height, const uchar *bits, bool isXbitmap)
+
+    Constructs a bitmap with the given \a width and \a height, and
+    sets the contents to the \a bits supplied. The \a isXbitmap flag
+    should be true if \a bits was generated by the X11 bitmap
+    program.
+
+    Use the static fromData() function instead. If \a isXbitmap is
+    true, use the default bit order(QImage_FormatMonoLSB) otherwise
+    use QImage::Format_Mono.
+
+    \omit
+    The X bitmap bit order is little endian.  The QImage
+    documentation discusses bit order of monochrome images. Opposed to
+    QImage, the data has to be byte aligned.
+
+    Example (creates an arrow bitmap):
+    \snippet doc/src/snippets/code/src_gui_image_qbitmap.cpp 0
+    \endomit
+*/
+
+
+/*!
+  \fn QBitmap::QBitmap(const QSize &size, const uchar *bits, bool isXbitmap)
+
+    \overload
+
+    Constructs a bitmap with the given \a size, and sets the contents
+    to the \a bits supplied. The \a isXbitmap flag should be true if
+    \a bits was generated by the X11 bitmap program.
+
+    \omit
+    The X bitmap bit order is little endian.  The QImage documentation
+    discusses bit order of monochrome images.
+    \endomit
+
+    Use the static fromData() function instead. If \a isXbitmap is
+    true, use the default bit order(QImage_FormatMonoLSB) otherwise
+    use QImage::Format_Mono.
+*/
+#endif
+
+QT_END_NAMESPACE