koffice/lib/kofficecore/KoPictureImage.cpp

/* This file is part of the KDE project
   Copyright (c) 2001 Simon Hausmann <hausmann@kde.org>
   Copyright (C) 2002, 2003 Nicolas GOUTTE <goutte@kde.org>

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.

   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public License
   along with this library; see the file COPYING.LIB.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
*/

#include "KoPictureImage.h"
#include "KoPictureKey.h"

#include <kdebug.h>
#include <kmimetype.h>

#include <qbuffer.h>
#include <qpainter.h>
#include <qimage.h>
#include <qpixmap.h>
#include <qapplication.h>
#include <qdragobject.h>

KoPictureImage::KoPictureImage(void) : m_cacheIsInFastMode(true)
{
    // Forbid QPixmap to cache the X-Window resources (Yes, it is slower!)
    m_cachedPixmap.setOptimization(QPixmap::MemoryOptim);
}

KoPictureImage::~KoPictureImage(void)
{
}

KoPictureBase* KoPictureImage::newCopy(void) const
{
    return new KoPictureImage(*this);
}

KoPictureType::Type KoPictureImage::getType(void) const
{
    return KoPictureType::TypeImage;
}

bool KoPictureImage::isNull(void) const
{
    return m_originalImage.isNull();
}

void KoPictureImage::scaleAndCreatePixmap(const QSize& size, bool fastMode)
{
    if ((size==m_cachedSize)
        && ((fastMode) || (!m_cacheIsInFastMode)))
    {
        // The cached pixmap has already the right size
        // and:
        // - we are in fast mode (We do not care if the re-size was done slowly previously)
        // - the re-size was already done in slow mode
        return;
    }

    // Slow mode can be very slow, especially at high zoom levels -> configurable
    if ( !isSlowResizeModeAllowed() )
    {
        kdDebug(30003) << "User has disallowed slow mode!" << endl;
        fastMode = true;
    }

    // Use QImage::scale if we have fastMode==true
    if ( fastMode )
    {
        m_cachedPixmap.convertFromImage(m_originalImage.scale( size ), QPixmap::Color); // Always color or else B/W can be reversed
        m_cacheIsInFastMode=true;
    }
    else
    {
        m_cachedPixmap.convertFromImage(m_originalImage.smoothScale( size ), QPixmap::Color); // Always color or else B/W can be reversed
        m_cacheIsInFastMode=false;
    }
    m_cachedSize=size;
}

void KoPictureImage::draw(QPainter& painter, int x, int y, int width, int height, int sx, int sy, int sw, int sh, bool fastMode)
{
    //kdDebug() << "KoImage::draw currentSize:" << currentSize.width() << "x" << currentSize.height() << endl;
    if ( !width || !height )
        return;
    QSize origSize = getOriginalSize();
    const bool scaleImage = painter.device()->isExtDev() // we are printing
        && ((width <= origSize.width()) || (height <= origSize.height()));
    if( scaleImage )
    {
        // use full resolution of image
        double xScale = double(width) / double(origSize.width());
        double yScale = double(height) / double(origSize.height());

        painter.save();
        painter.translate( x, y );
        painter.scale( xScale, yScale );
        // Note that sx, sy, sw and sh are unused in this case. Not a problem, since it's about printing.
        // Note 2: we do not cache the QPixmap. As we are printing, the next time we will probably
        //   need again the screen version.
        painter.drawImage(0, 0, m_originalImage);
        painter.restore();
    }
    else
    {
        QSize screenSize( width, height );
        //kdDebug() << "KoPictureImage::draw screenSize=" << screenSize.width() << "x" << screenSize.height() << endl;

        scaleAndCreatePixmap(screenSize, fastMode);

        // sx,sy,sw,sh is meant to be used as a cliprect on the pixmap, but drawPixmap
        // translates it to the (x,y) point -> we need (x+sx, y+sy).
        painter.drawPixmap( x + sx, y + sy, m_cachedPixmap, sx, sy, sw, sh );
    }
}

bool KoPictureImage::loadData(const QByteArray& array, const QString& /* extension*/ )
{
    m_rawData=array;
    // Second, create the original image
    QBuffer buffer(m_rawData);
    buffer.open(IO_ReadWrite);
    QImageIO imageIO(&buffer,NULL);

    if (!imageIO.read())
    {
        buffer.close();
        kdError(30003) << "Image could not be loaded!" << endl;
        return false;
    }
    buffer.close();
    m_originalImage=imageIO.image();

    return true;
}

bool KoPictureImage::save(QIODevice* io) const
{
    kdDebug() << k_funcinfo << "writing raw data. size=" << m_rawData.size() << endl;
    // We save the raw data, to avoid damaging the file by many load/save cycles (especially for JPEG)
    Q_ULONG size=io->writeBlock(m_rawData); // WARNING: writeBlock returns Q_LONG but size() Q_ULONG!
    return (size==m_rawData.size());
}

QSize KoPictureImage::getOriginalSize(void) const
{
    return m_originalImage.size();
}

QPixmap KoPictureImage::generatePixmap(const QSize& size, bool smoothScale)
{
    scaleAndCreatePixmap(size,!smoothScale);
    return m_cachedPixmap;
}

QString KoPictureImage::getMimeType(const QString& extension) const
{
    QString fileName("/tmp/temp.");
    fileName+=extension;
    // Find the mimetype only by the extension, not by file content (as the file is empty!)
    const QString mimetype( KMimeType::findByPath( fileName, 0 ,true )->name() );
    // ### TODO: use KMimeType::findByContent (but then the mimetype probably need to be cached)
    kdDebug(30003) << "Image is mime type: " << mimetype << endl;
    return mimetype;
}

QDragObject* KoPictureImage::dragObject( QWidget *dragSource, const char *name )
{
    return new QImageDrag( m_originalImage, dragSource, name );
}

QImage KoPictureImage::generateImage(const QSize& size)
{
    // We do not cache the image, as we will seldom need it again.
    return m_originalImage.smoothScale( size );
}

void KoPictureImage::clearCache(void)
{
    m_cachedPixmap.resize(0, 0);
    m_cacheIsInFastMode=true;
    m_cachedSize=QSize();
}