annotate layer/ImageLayer.cpp @ 314:7b96a3261e1c

* "Align mode"

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2006 Chris Cannam.
    
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

#include "ImageLayer.h"

#include "data/model/Model.h"
#include "base/RealTime.h"
#include "base/Profiler.h"
#include "view/View.h"

#include "data/model/ImageModel.h"
#include "data/fileio/RemoteFile.h"

#include "widgets/ImageDialog.h"

#include <QPainter>
#include <QMouseEvent>
#include <QInputDialog>
#include <QMutexLocker>

#include <iostream>
#include <cmath>

ImageLayer::ImageMap
ImageLayer::m_images;

QMutex
ImageLayer::m_imageMapMutex;

ImageLayer::ImageLayer() :
    Layer(),
    m_model(0),
    m_editing(false),
    m_originalPoint(0, "", ""),
    m_editingPoint(0, "", ""),
    m_editingCommand(0)
{
}

ImageLayer::~ImageLayer()
{
    for (RemoteFileMap::iterator i = m_remoteFiles.begin();
         i != m_remoteFiles.end(); ++i) {
        delete i->second;
    }
}

void
ImageLayer::setModel(ImageModel *model)
{
    if (m_model == model) return;
    m_model = model;

    connect(m_model, SIGNAL(modelChanged()),
            this, SIGNAL(modelChanged()));
    connect(m_model, SIGNAL(modelChanged(size_t, size_t)),
	    this, SIGNAL(modelChanged(size_t, size_t)));

    connect(m_model, SIGNAL(completionChanged()),
	    this, SIGNAL(modelCompletionChanged()));

//    connect(m_model, SIGNAL(modelChanged()),
//            this, SLOT(checkAddRemotes()));

//    std::cerr << "ImageLayer::setModel(" << model << ")" << std::endl;

//    checkAddRemotes();

    emit modelReplaced();
}

Layer::PropertyList
ImageLayer::getProperties() const
{
    return Layer::getProperties();
}

QString
ImageLayer::getPropertyLabel(const PropertyName &name) const
{
    return "";
}

Layer::PropertyType
ImageLayer::getPropertyType(const PropertyName &name) const
{
    return Layer::getPropertyType(name);
}

int
ImageLayer::getPropertyRangeAndValue(const PropertyName &name,
				    int *min, int *max, int *deflt) const
{
    return Layer::getPropertyRangeAndValue(name, min, max, deflt);
}

QString
ImageLayer::getPropertyValueLabel(const PropertyName &name,
				 int value) const
{
    return Layer::getPropertyValueLabel(name, value);
}

void
ImageLayer::setProperty(const PropertyName &name, int value)
{
    Layer::setProperty(name, value);
}

bool
ImageLayer::getValueExtents(float &, float &, bool &, QString &) const
{
    return false;
}

bool
ImageLayer::isLayerScrollable(const View *v) const
{
    return true;
}


ImageModel::PointList
ImageLayer::getLocalPoints(View *v, int x, int y) const
{
    if (!m_model) return ImageModel::PointList();

//    std::cerr << "ImageLayer::getLocalPoints(" << x << "," << y << "):";
    const ImageModel::PointList &points(m_model->getPoints());

    ImageModel::PointList rv;

    for (ImageModel::PointList::const_iterator i = points.begin();
	 i != points.end(); ) {

	const ImageModel::Point &p(*i);
	int px = v->getXForFrame(p.frame);
        if (px > x) break;

        ++i;
        if (i != points.end()) {
            int nx = v->getXForFrame((*i).frame);
            if (nx < x) {
                // as we aim not to overlap the images, if the following
                // image begins to the left of a point then the current
                // one may be assumed to end to the left of it as well.
                continue;
            }
        }

        // this image is a candidate, test it properly

        int width = 32;
        if (m_scaled[v].find(p.image) != m_scaled[v].end()) {
            width = m_scaled[v][p.image].width();
//            std::cerr << "scaled width = " << width << std::endl;
        }

        if (x >= px && x < px + width) {
            rv.insert(p);
        }
    }

//    std::cerr << rv.size() << " point(s)" << std::endl;

    return rv;
}

QString
ImageLayer::getFeatureDescription(View *v, QPoint &pos) const
{
    int x = pos.x();

    if (!m_model || !m_model->getSampleRate()) return "";

    ImageModel::PointList points = getLocalPoints(v, x, pos.y());

    if (points.empty()) {
	if (!m_model->isReady()) {
	    return tr("In progress");
	} else {
	    return "";
	}
    }

    long useFrame = points.begin()->frame;

    RealTime rt = RealTime::frame2RealTime(useFrame, m_model->getSampleRate());

    QString text;
/*    
    if (points.begin()->label == "") {
	text = QString(tr("Time:\t%1\nHeight:\t%2\nLabel:\t%3"))
	    .arg(rt.toText(true).c_str())
	    .arg(points.begin()->height)
	    .arg(points.begin()->label);
    }

    pos = QPoint(v->getXForFrame(useFrame),
		 getYForHeight(v, points.begin()->height));
*/
    return text;
}


//!!! too much overlap with TimeValueLayer/TimeInstantLayer/TextLayer

bool
ImageLayer::snapToFeatureFrame(View *v, int &frame,
			      size_t &resolution,
			      SnapType snap) const
{
    if (!m_model) {
	return Layer::snapToFeatureFrame(v, frame, resolution, snap);
    }

    resolution = m_model->getResolution();
    ImageModel::PointList points;

    if (snap == SnapNeighbouring) {
	
	points = getLocalPoints(v, v->getXForFrame(frame), -1);
	if (points.empty()) return false;
	frame = points.begin()->frame;
	return true;
    }    

    points = m_model->getPoints(frame, frame);
    int snapped = frame;
    bool found = false;

    for (ImageModel::PointList::const_iterator i = points.begin();
	 i != points.end(); ++i) {

	if (snap == SnapRight) {

	    if (i->frame > frame) {
		snapped = i->frame;
		found = true;
		break;
	    }

	} else if (snap == SnapLeft) {

	    if (i->frame <= frame) {
		snapped = i->frame;
		found = true; // don't break, as the next may be better
	    } else {
		break;
	    }

	} else { // nearest

	    ImageModel::PointList::const_iterator j = i;
	    ++j;

	    if (j == points.end()) {

		snapped = i->frame;
		found = true;
		break;

	    } else if (j->frame >= frame) {

		if (j->frame - frame < frame - i->frame) {
		    snapped = j->frame;
		} else {
		    snapped = i->frame;
		}
		found = true;
		break;
	    }
	}
    }

    frame = snapped;
    return found;
}

void
ImageLayer::paint(View *v, QPainter &paint, QRect rect) const
{
    if (!m_model || !m_model->isOK()) return;

    int sampleRate = m_model->getSampleRate();
    if (!sampleRate) return;

//    Profiler profiler("ImageLayer::paint", true);

//    int x0 = rect.left(), x1 = rect.right();
    int x0 = 0, x1 = v->width();

    long frame0 = v->getFrameForX(x0);
    long frame1 = v->getFrameForX(x1);

    ImageModel::PointList points(m_model->getPoints(frame0, frame1));
    if (points.empty()) return;

    paint.save();
    paint.setClipRect(rect.x(), 0, rect.width(), v->height());

    QColor penColour;
    penColour = v->getForeground();

    QColor brushColour;
    brushColour = v->getBackground();

    int h, s, val;
    brushColour.getHsv(&h, &s, &val);
    brushColour.setHsv(h, s, 255, 240);

    paint.setPen(penColour);
    paint.setBrush(brushColour);
    paint.setRenderHint(QPainter::Antialiasing, true);

    for (ImageModel::PointList::const_iterator i = points.begin();
	 i != points.end(); ++i) {

	const ImageModel::Point &p(*i);

	int x = v->getXForFrame(p.frame);

        int nx = x + 2000;
        ImageModel::PointList::const_iterator j = i;
        ++j;
        if (j != points.end()) {
            int jx = v->getXForFrame(j->frame);
            if (jx < nx) nx = jx;
        }

        drawImage(v, paint, p, x, nx);
    }

    paint.setRenderHint(QPainter::Antialiasing, false);
    paint.restore();
}

void
ImageLayer::drawImage(View *v, QPainter &paint, const ImageModel::Point &p,
                      int x, int nx) const
{
    QString label = p.label;
    QString imageName = p.image;

    QImage image;
    QString additionalText;

    QSize imageSize;
    if (!getImageOriginalSize(imageName, imageSize)) {
        image = QImage(":icons/emptypage.png");
        imageSize = image.size();
        additionalText = imageName;
    }

    int topMargin = 10;
    int bottomMargin = 10;
    int spacing = 5;

    if (v->height() < 100) {
        topMargin = 5;
        bottomMargin = 5;
    }

    int maxBoxHeight = v->height() - topMargin - bottomMargin;

    int availableWidth = nx - x - 3;
    if (availableWidth < 20) availableWidth = 20;

    QRect labelRect;

    if (label != "") {

        int likelyHeight = v->height() / 4;

        int likelyWidth = // available height times image aspect
            ((maxBoxHeight - likelyHeight) * imageSize.width())
            / imageSize.height();

        if (likelyWidth > imageSize.width()) {
            likelyWidth = imageSize.width();
        }

        if (likelyWidth > availableWidth) {
            likelyWidth = availableWidth;
        }

        int singleWidth = paint.fontMetrics().width(label);
        if (singleWidth < availableWidth && singleWidth < likelyWidth * 2) {
            likelyWidth = singleWidth + 4;
        }

        labelRect = paint.fontMetrics().boundingRect
            (QRect(0, 0, likelyWidth, likelyHeight),
             Qt::AlignCenter | Qt::TextWordWrap, label);

        labelRect.setWidth(labelRect.width() + 6);
    }

    if (image.isNull()) {
        image = getImage(v, imageName,
                         QSize(availableWidth,
                               maxBoxHeight - labelRect.height()));
    }

    int boxWidth = image.width();
    if (boxWidth < labelRect.width()) {
        boxWidth = labelRect.width();
    }

    int boxHeight = image.height();
    if (label != "") {
        boxHeight += labelRect.height() + spacing;
    }

    int division = image.height();

    if (additionalText != "") {

        paint.save();

        QFont font(paint.font());
        font.setItalic(true);
        paint.setFont(font);

        int tw = paint.fontMetrics().width(additionalText);
        if (tw > availableWidth) {
            tw = availableWidth;
        }
        if (boxWidth < tw) {
            boxWidth = tw;
        }
        boxHeight += paint.fontMetrics().height();
        division += paint.fontMetrics().height();
    }                

    bottomMargin = v->height() - topMargin - boxHeight;
    if (bottomMargin > topMargin + v->height()/7) {
        topMargin += v->height()/8;
        bottomMargin -= v->height()/8;
    }

    paint.drawRect(x - 1,
                   topMargin - 1,
                   boxWidth + 2,
                   boxHeight + 2);

    int imageY;
    if (label != "") {
        imageY = topMargin + labelRect.height() + spacing;
    } else {
        imageY = topMargin;
    }

    paint.drawImage(x + (boxWidth - image.width())/2,
                    imageY,
                    image);

    if (additionalText != "") {
        paint.drawText(x,
                       imageY + image.height() + paint.fontMetrics().ascent(),
                       additionalText);
        paint.restore();
    }

    if (label != "") {
        paint.drawLine(x,
                       topMargin + labelRect.height() + spacing,
                       x + boxWidth, 
                       topMargin + labelRect.height() + spacing);

        paint.drawText(QRect(x,
                             topMargin,
                             boxWidth,
                             labelRect.height()),
                       Qt::AlignCenter | Qt::TextWordWrap,
                       label);
    }
}

void
ImageLayer::setLayerDormant(const View *v, bool dormant)
{
    if (dormant) {
        // Delete the images named in the view's scaled map from the
        // general image map as well.  They can always be re-loaded
        // if it turns out another view still needs them.
        QMutexLocker locker(&m_imageMapMutex);
        for (ImageMap::iterator i = m_scaled[v].begin();
             i != m_scaled[v].end(); ++i) {
            m_images.erase(i->first);
        }
        m_scaled.erase(v);
    }
}

//!!! how to reap no-longer-used images?

bool
ImageLayer::getImageOriginalSize(QString name, QSize &size) const
{
//    std::cerr << "getImageOriginalSize: \"" << name.toStdString() << "\"" << std::endl;

    QMutexLocker locker(&m_imageMapMutex);
    if (m_images.find(name) == m_images.end()) {
//        std::cerr << "don't have, trying to open local" << std::endl;
        m_images[name] = QImage(getLocalFilename(name));
    }
    if (m_images[name].isNull()) {
//        std::cerr << "null image" << std::endl;
        return false;
    } else {
        size = m_images[name].size();
        return true;
    }
}

QImage 
ImageLayer::getImage(View *v, QString name, QSize maxSize) const
{
    bool need = false;

//    std::cerr << "ImageLayer::getImage(" << v << ", " << name.toStdString() << ", ("
//              << maxSize.width() << "x" << maxSize.height() << "))" << std::endl;

    if (!m_scaled[v][name].isNull()  &&
        ((m_scaled[v][name].width()  == maxSize.width() &&
          m_scaled[v][name].height() <= maxSize.height()) ||
         (m_scaled[v][name].width()  <= maxSize.width() &&
          m_scaled[v][name].height() == maxSize.height()))) {
//        std::cerr << "cache hit" << std::endl;
        return m_scaled[v][name];
    }

    QMutexLocker locker(&m_imageMapMutex);

    if (m_images.find(name) == m_images.end()) {
        m_images[name] = QImage(getLocalFilename(name));
    }

    if (m_images[name].isNull()) {
//        std::cerr << "null image" << std::endl;
        m_scaled[v][name] = QImage();
    } else if (m_images[name].width() <= maxSize.width() &&
               m_images[name].height() <= maxSize.height()) {
        m_scaled[v][name] = m_images[name];
    } else {
        m_scaled[v][name] =
            m_images[name].scaled(maxSize,
                                  Qt::KeepAspectRatio,
                                  Qt::SmoothTransformation);
    }

    return m_scaled[v][name];
}

void
ImageLayer::drawStart(View *v, QMouseEvent *e)
{
//    std::cerr << "ImageLayer::drawStart(" << e->x() << "," << e->y() << ")" << std::endl;

    if (!m_model) {
	std::cerr << "ImageLayer::drawStart: no model" << std::endl;
	return;
    }

    long frame = v->getFrameForX(e->x());
    if (frame < 0) frame = 0;
    frame = frame / m_model->getResolution() * m_model->getResolution();

    m_editingPoint = ImageModel::Point(frame, "", "");
    m_originalPoint = m_editingPoint;

    if (m_editingCommand) m_editingCommand->finish();
    m_editingCommand = new ImageModel::EditCommand(m_model, "Add Image");
    m_editingCommand->addPoint(m_editingPoint);

    m_editing = true;
}

void
ImageLayer::drawDrag(View *v, QMouseEvent *e)
{
//    std::cerr << "ImageLayer::drawDrag(" << e->x() << "," << e->y() << ")" << std::endl;

    if (!m_model || !m_editing) return;

    long frame = v->getFrameForX(e->x());
    if (frame < 0) frame = 0;
    frame = frame / m_model->getResolution() * m_model->getResolution();

    m_editingCommand->deletePoint(m_editingPoint);
    m_editingPoint.frame = frame;
    m_editingCommand->addPoint(m_editingPoint);
}

void
ImageLayer::drawEnd(View *v, QMouseEvent *)
{
//    std::cerr << "ImageLayer::drawEnd(" << e->x() << "," << e->y() << ")" << std::endl;
    if (!m_model || !m_editing) return;

    bool ok = false;

    ImageDialog dialog(tr("Select image"), "", "");

    if (dialog.exec() == QDialog::Accepted) {

        checkAddRemote(dialog.getImage());

	ImageModel::ChangeImageCommand *command =
	    new ImageModel::ChangeImageCommand
            (m_model, m_editingPoint, dialog.getImage(), dialog.getLabel());
	m_editingCommand->addCommand(command);
    } else {
        m_editingCommand->deletePoint(m_editingPoint);
    }

    m_editingCommand->finish();
    m_editingCommand = 0;
    m_editing = false;
}

bool
ImageLayer::addImage(long frame, QString url)
{
    QImage image(getLocalFilename(url));
    if (image.isNull()) {
        delete m_remoteFiles[url];
        m_remoteFiles.erase(url);
        return false;
    }

    ImageModel::Point point(frame, url, "");
    ImageModel::EditCommand *command =
        new ImageModel::EditCommand(m_model, "Add Image");
    command->addPoint(point);
    command->finish();
    return true;
}

void
ImageLayer::editStart(View *v, QMouseEvent *e)
{
//    std::cerr << "ImageLayer::editStart(" << e->x() << "," << e->y() << ")" << std::endl;

    if (!m_model) return;

    ImageModel::PointList points = getLocalPoints(v, e->x(), e->y());
    if (points.empty()) return;

    m_editOrigin = e->pos();
    m_editingPoint = *points.begin();
    m_originalPoint = m_editingPoint;

    if (m_editingCommand) {
	m_editingCommand->finish();
	m_editingCommand = 0;
    }

    m_editing = true;
}

void
ImageLayer::editDrag(View *v, QMouseEvent *e)
{
    if (!m_model || !m_editing) return;

    long frameDiff = v->getFrameForX(e->x()) - v->getFrameForX(m_editOrigin.x());
    long frame = m_originalPoint.frame + frameDiff;

    if (frame < 0) frame = 0;
    frame = (frame / m_model->getResolution()) * m_model->getResolution();

    if (!m_editingCommand) {
	m_editingCommand = new ImageModel::EditCommand(m_model, tr("Move Image"));
    }

    m_editingCommand->deletePoint(m_editingPoint);
    m_editingPoint.frame = frame;
    m_editingCommand->addPoint(m_editingPoint);
}

void
ImageLayer::editEnd(View *, QMouseEvent *)
{
//    std::cerr << "ImageLayer::editEnd(" << e->x() << "," << e->y() << ")" << std::endl;
    if (!m_model || !m_editing) return;

    if (m_editingCommand) {
	m_editingCommand->finish();
    }
    
    m_editingCommand = 0;
    m_editing = false;
}

bool
ImageLayer::editOpen(View *v, QMouseEvent *e)
{
    if (!m_model) return false;

    ImageModel::PointList points = getLocalPoints(v, e->x(), e->y());
    if (points.empty()) return false;

    QString image = points.begin()->image;
    QString label = points.begin()->label;

    ImageDialog dialog(tr("Select image"),
                       image,
                       label);

    if (dialog.exec() == QDialog::Accepted) {

        checkAddRemote(dialog.getImage());

	ImageModel::ChangeImageCommand *command =
	    new ImageModel::ChangeImageCommand
            (m_model, *points.begin(), dialog.getImage(), dialog.getLabel());

        CommandHistory::getInstance()->addCommand(command);
    }

    return true;
}    

void
ImageLayer::moveSelection(Selection s, size_t newStartFrame)
{
    if (!m_model) return;

    ImageModel::EditCommand *command =
	new ImageModel::EditCommand(m_model, tr("Drag Selection"));

    ImageModel::PointList points =
	m_model->getPoints(s.getStartFrame(), s.getEndFrame());

    for (ImageModel::PointList::iterator i = points.begin();
	 i != points.end(); ++i) {

	if (s.contains(i->frame)) {
	    ImageModel::Point newPoint(*i);
	    newPoint.frame = i->frame + newStartFrame - s.getStartFrame();
	    command->deletePoint(*i);
	    command->addPoint(newPoint);
	}
    }

    command->finish();
}

void
ImageLayer::resizeSelection(Selection s, Selection newSize)
{
    if (!m_model) return;

    ImageModel::EditCommand *command =
	new ImageModel::EditCommand(m_model, tr("Resize Selection"));

    ImageModel::PointList points =
	m_model->getPoints(s.getStartFrame(), s.getEndFrame());

    double ratio =
	double(newSize.getEndFrame() - newSize.getStartFrame()) /
	double(s.getEndFrame() - s.getStartFrame());

    for (ImageModel::PointList::iterator i = points.begin();
	 i != points.end(); ++i) {

	if (s.contains(i->frame)) {

	    double target = i->frame;
	    target = newSize.getStartFrame() + 
		double(target - s.getStartFrame()) * ratio;

	    ImageModel::Point newPoint(*i);
	    newPoint.frame = lrint(target);
	    command->deletePoint(*i);
	    command->addPoint(newPoint);
	}
    }

    command->finish();
}

void
ImageLayer::deleteSelection(Selection s)
{
    if (!m_model) return;

    ImageModel::EditCommand *command =
	new ImageModel::EditCommand(m_model, tr("Delete Selection"));

    ImageModel::PointList points =
	m_model->getPoints(s.getStartFrame(), s.getEndFrame());

    for (ImageModel::PointList::iterator i = points.begin();
	 i != points.end(); ++i) {
	if (s.contains(i->frame)) command->deletePoint(*i);
    }

    command->finish();
}

void
ImageLayer::copy(Selection s, Clipboard &to)
{
    if (!m_model) return;

    ImageModel::PointList points =
	m_model->getPoints(s.getStartFrame(), s.getEndFrame());

    for (ImageModel::PointList::iterator i = points.begin();
	 i != points.end(); ++i) {
	if (s.contains(i->frame)) {
            //!!! inadequate
            Clipboard::Point point(i->frame, i->label);
            to.addPoint(point);
        }
    }
}

bool
ImageLayer::paste(const Clipboard &from, int frameOffset, bool /* interactive */)
{
    if (!m_model) return false;

    const Clipboard::PointList &points = from.getPoints();

    ImageModel::EditCommand *command =
	new ImageModel::EditCommand(m_model, tr("Paste"));

    for (Clipboard::PointList::const_iterator i = points.begin();
         i != points.end(); ++i) {
        
        if (!i->haveFrame()) continue;
        size_t frame = 0;
        if (frameOffset > 0 || -frameOffset < i->getFrame()) {
            frame = i->getFrame() + frameOffset;
        }
        ImageModel::Point newPoint(frame);

        //!!! inadequate
        
        if (i->haveLabel()) {
            newPoint.label = i->getLabel();
        } else if (i->haveValue()) {
            newPoint.label = QString("%1").arg(i->getValue());
        } else {
            newPoint.label = tr("New Point");
        }
        
        command->addPoint(newPoint);
    }

    command->finish();
    return true;
}

QString
ImageLayer::getLocalFilename(QString img) const
{
    if (m_remoteFiles.find(img) == m_remoteFiles.end()) {
        checkAddRemote(img);
        if (m_remoteFiles.find(img) == m_remoteFiles.end()) {
            return img;
        }
    }
    return m_remoteFiles[img]->getLocalFilename();
}

void
ImageLayer::checkAddRemote(QString img) const
{
    if (RemoteFile::isRemote(img)) {

        std::cerr << "ImageLayer::checkAddRemote(" << img.toStdString() << "): yes, trying..." << std::endl;

        if (m_remoteFiles.find(img) != m_remoteFiles.end()) {
            return;
        }

        QUrl url(img);
        if (RemoteFile::canHandleScheme(url)) {
            RemoteFile *rf = new RemoteFile(url);
            if (rf->isOK()) {
                std::cerr << "ok, adding it (local filename = " << rf->getLocalFilename().toStdString() << ")" << std::endl;
                m_remoteFiles[img] = rf;
                connect(rf, SIGNAL(ready()), this, SLOT(remoteFileReady()));
            } else {
                delete rf;
            }
        }
    }
}

void
ImageLayer::checkAddRemotes()
{
    const ImageModel::PointList &points(m_model->getPoints());

    for (ImageModel::PointList::const_iterator i = points.begin();
	 i != points.end(); ++i) {
        
        checkAddRemote((*i).image);
    }
}

void
ImageLayer::remoteFileReady()
{
//    std::cerr << "ImageLayer::remoteFileReady" << std::endl;

    RemoteFile *rf = dynamic_cast<RemoteFile *>(sender());
    if (!rf) return;

    QString img;
    for (RemoteFileMap::const_iterator i = m_remoteFiles.begin();
         i != m_remoteFiles.end(); ++i) {
        if (i->second == rf) {
            img = i->first;
//            std::cerr << "it's image \"" << img.toStdString() << "\"" << std::endl;
            break;
        }
    }
    if (img == "") return;

    QMutexLocker locker(&m_imageMapMutex);
    m_images.erase(img);
    for (ViewImageMap::iterator i = m_scaled.begin(); i != m_scaled.end(); ++i) {
        i->second.erase(img);
        emit modelChanged();
    }
}

QString
ImageLayer::toXmlString(QString indent, QString extraAttributes) const
{
    return Layer::toXmlString(indent, extraAttributes);
}

void
ImageLayer::setProperties(const QXmlAttributes &attributes)
{
}