annotate view/View.cpp @ 317:e251c3599ea8

* Make RemoteFile far more pervasive, and use it for local files as well
  so that we can handle both transparently.  Make it shallow copy with
  reference counting, so it can be used by value without having to worry
  about the cache file lifetime.  Use RemoteFile for MainWindow file-open
  functions, etc

/* -*- 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 "View.h"
#include "layer/Layer.h"
#include "data/model/Model.h"
#include "base/ZoomConstraint.h"
#include "base/Profiler.h"
#include "base/Pitch.h"

#include "layer/TimeRulerLayer.h"
#include "layer/SingleColourLayer.h"
#include "data/model/PowerOfSqrtTwoZoomConstraint.h"
#include "data/model/RangeSummarisableTimeValueModel.h"

#include <QPainter>
#include <QPaintEvent>
#include <QRect>
#include <QApplication>
#include <QProgressDialog>
#include <QTextStream>

#include <iostream>
#include <cassert>
#include <math.h>

//#define DEBUG_VIEW_WIDGET_PAINT 1

using std::cerr;
using std::endl;

View::View(QWidget *w, bool showProgress) :
    QFrame(w),
    m_centreFrame(0),
    m_zoomLevel(1024),
    m_followPan(true),
    m_followZoom(true),
    m_followPlay(PlaybackScrollPage),
    m_playPointerFrame(0),
    m_showProgress(showProgress),
    m_cache(0),
    m_cacheCentreFrame(0),
    m_cacheZoomLevel(1024),
    m_selectionCached(false),
    m_deleting(false),
    m_haveSelectedLayer(false),
    m_manager(0),
    m_propertyContainer(new ViewPropertyContainer(this))
{
}

View::~View()
{
//    std::cerr << "View::~View(" << this << ")" << std::endl;

    m_deleting = true;
    delete m_propertyContainer;
}

PropertyContainer::PropertyList
View::getProperties() const
{
    PropertyContainer::PropertyList list;
    list.push_back("Global Scroll");
    list.push_back("Global Zoom");
    list.push_back("Follow Playback");
    return list;
}

QString
View::getPropertyLabel(const PropertyName &pn) const
{
    if (pn == "Global Scroll") return tr("Global Scroll");
    if (pn == "Global Zoom") return tr("Global Zoom");
    if (pn == "Follow Playback") return tr("Follow Playback");
    return "";
}

PropertyContainer::PropertyType
View::getPropertyType(const PropertyContainer::PropertyName &name) const
{
    if (name == "Global Scroll") return PropertyContainer::ToggleProperty;
    if (name == "Global Zoom") return PropertyContainer::ToggleProperty;
    if (name == "Follow Playback") return PropertyContainer::ValueProperty;
    return PropertyContainer::InvalidProperty;
}

int
View::getPropertyRangeAndValue(const PropertyContainer::PropertyName &name,
			       int *min, int *max, int *deflt) const
{
    if (deflt) *deflt = 1;
    if (name == "Global Scroll") return m_followPan;
    if (name == "Global Zoom") return m_followZoom;
    if (name == "Follow Playback") {
	if (min) *min = 0;
	if (max) *max = 2;
        if (deflt) *deflt = int(PlaybackScrollPage);
	return int(m_followPlay);
    }
    if (min) *min = 0;
    if (max) *max = 0;
    if (deflt) *deflt = 0;
    return 0;
}

QString
View::getPropertyValueLabel(const PropertyContainer::PropertyName &name,
			    int value) const
{
    if (name == "Follow Playback") {
	switch (value) {
	default:
	case 0: return tr("Scroll");
	case 1: return tr("Page");
	case 2: return tr("Off");
	}
    }
    return tr("<unknown>");
}

void
View::setProperty(const PropertyContainer::PropertyName &name, int value)
{
    if (name == "Global Scroll") {
	setFollowGlobalPan(value != 0);
    } else if (name == "Global Zoom") {
	setFollowGlobalZoom(value != 0);
    } else if (name == "Follow Playback") {
	switch (value) {
	default:
	case 0: setPlaybackFollow(PlaybackScrollContinuous); break;
	case 1: setPlaybackFollow(PlaybackScrollPage); break;
	case 2: setPlaybackFollow(PlaybackIgnore); break;
	}
    }
}

size_t
View::getPropertyContainerCount() const
{
    return m_layers.size() + 1; // the 1 is for me
}

const PropertyContainer *
View::getPropertyContainer(size_t i) const
{
    return (const PropertyContainer *)(((View *)this)->
				       getPropertyContainer(i));
}

PropertyContainer *
View::getPropertyContainer(size_t i)
{
    if (i == 0) return m_propertyContainer;
    return m_layers[i-1];
}

bool
View::getValueExtents(QString unit, float &min, float &max, bool &log) const
{
    bool have = false;

    for (LayerList::const_iterator i = m_layers.begin();
         i != m_layers.end(); ++i) { 

        QString layerUnit;
        float layerMin = 0.0, layerMax = 0.0;
        float displayMin = 0.0, displayMax = 0.0;
        bool layerLog = false;

        if ((*i)->getValueExtents(layerMin, layerMax, layerLog, layerUnit) &&
            layerUnit.toLower() == unit.toLower()) {

            if ((*i)->getDisplayExtents(displayMin, displayMax)) {

                min = displayMin;
                max = displayMax;
                log = layerLog;
                have = true;
                break;

            } else {

                if (!have || layerMin < min) min = layerMin;
                if (!have || layerMax > max) max = layerMax;
                if (layerLog) log = true;
                have = true;
            }
        }
    }

    return have;
}

int
View::getTextLabelHeight(const Layer *layer, QPainter &paint) const
{
    std::map<int, Layer *> sortedLayers;

    for (LayerList::const_iterator i = m_layers.begin();
         i != m_layers.end(); ++i) { 
        if ((*i)->needsTextLabelHeight()) {
            sortedLayers[getObjectExportId(*i)] = *i;
        }
    }

    int y = 15 + paint.fontMetrics().ascent();

    for (std::map<int, Layer *>::const_iterator i = sortedLayers.begin();
         i != sortedLayers.end(); ++i) {
        if (i->second == layer) return y;
        y += paint.fontMetrics().height();
    }

    return y;
}

void
View::propertyContainerSelected(View *client, PropertyContainer *pc)
{
    if (client != this) return;
    
    if (pc == m_propertyContainer) {
	if (m_haveSelectedLayer) {
	    m_haveSelectedLayer = false;
	    update();
	}
	return;
    }

    delete m_cache;
    m_cache = 0;

    Layer *selectedLayer = 0;

    for (LayerList::iterator i = m_layers.begin(); i != m_layers.end(); ++i) {
	if (*i == pc) {
	    selectedLayer = *i;
	    m_layers.erase(i);
	    break;
	}
    }

    if (selectedLayer) {
	m_haveSelectedLayer = true;
	m_layers.push_back(selectedLayer);
	update();
    } else {
	m_haveSelectedLayer = false;
    }

    emit propertyContainerSelected(pc);
}

void
View::toolModeChanged()
{
//    std::cerr << "View::toolModeChanged(" << m_manager->getToolMode() << ")" << std::endl;
}

void
View::overlayModeChanged()
{
    delete m_cache;
    m_cache = 0;
    update();
}

void
View::zoomWheelsEnabledChanged()
{
    // subclass might override this
}

long
View::getStartFrame() const
{
    return getFrameForX(0);
}

size_t
View::getEndFrame() const
{
    return getFrameForX(width()) - 1;
}

void
View::setStartFrame(long f)
{
    setCentreFrame(f + m_zoomLevel * (width() / 2));
}

bool
View::setCentreFrame(size_t f, bool e)
{
    bool changeVisible = false;

    if (m_centreFrame != f) {

	int formerPixel = m_centreFrame / m_zoomLevel;

	m_centreFrame = f;

	int newPixel = m_centreFrame / m_zoomLevel;
	
	if (newPixel != formerPixel) {

#ifdef DEBUG_VIEW_WIDGET_PAINT
	    std::cout << "View(" << this << ")::setCentreFrame: newPixel " << newPixel << ", formerPixel " << formerPixel << std::endl;
#endif
	    update();

	    changeVisible = true;
	}

	if (e) emit centreFrameChanged(f, m_followPan, m_followPlay);
    }

    return changeVisible;
}

int
View::getXForFrame(long frame) const
{
    return (frame - getStartFrame()) / m_zoomLevel;
}

long
View::getFrameForX(int x) const
{
    long z = (long)m_zoomLevel;
    long frame = m_centreFrame - (width()/2) * z;
    frame = (frame / z) * z; // this is start frame
    return frame + x * z;
}

float
View::getYForFrequency(float frequency,
		       float minf,
		       float maxf, 
		       bool logarithmic) const
{
    int h = height();

    if (logarithmic) {

	static float lastminf = 0.0, lastmaxf = 0.0;
	static float logminf = 0.0, logmaxf = 0.0;

	if (lastminf != minf) {
	    lastminf = (minf == 0.0 ? 1.0 : minf);
	    logminf = log10f(minf);
	}
	if (lastmaxf != maxf) {
	    lastmaxf = (maxf < lastminf ? lastminf : maxf);
	    logmaxf = log10f(maxf);
	}

	if (logminf == logmaxf) return 0;
	return h - (h * (log10f(frequency) - logminf)) / (logmaxf - logminf);

    } else {
	
	if (minf == maxf) return 0;
	return h - (h * (frequency - minf)) / (maxf - minf);
    }
}

float
View::getFrequencyForY(int y,
		       float minf,
		       float maxf,
		       bool logarithmic) const
{
    int h = height();

    if (logarithmic) {

	static float lastminf = 0.0, lastmaxf = 0.0;
	static float logminf = 0.0, logmaxf = 0.0;

	if (lastminf != minf) {
	    lastminf = (minf == 0.0 ? 1.0 : minf);
	    logminf = log10f(minf);
	}
	if (lastmaxf != maxf) {
	    lastmaxf = (maxf < lastminf ? lastminf : maxf);
	    logmaxf = log10f(maxf);
	}

	if (logminf == logmaxf) return 0;
	return pow(10.f, logminf + ((logmaxf - logminf) * (h - y)) / h);

    } else {

	if (minf == maxf) return 0;
	return minf + ((h - y) * (maxf - minf)) / h;
    }
}

int
View::getZoomLevel() const
{
#ifdef DEBUG_VIEW_WIDGET_PAINT
//	std::cout << "zoom level: " << m_zoomLevel << std::endl;
#endif
    return m_zoomLevel;
}

void
View::setZoomLevel(size_t z)
{
    if (m_zoomLevel != int(z)) {
	m_zoomLevel = z;
	emit zoomLevelChanged(z, m_followZoom);
	update();
    }
}

bool
View::hasLightBackground() const
{
    bool darkPalette = false;
    if (m_manager) darkPalette = m_manager->getGlobalDarkBackground();

    Layer::ColourSignificance maxSignificance = Layer::ColourAbsent;
    bool mostSignificantHasDarkBackground = false;
    
    for (LayerList::const_iterator i = m_layers.begin();
         i != m_layers.end(); ++i) {

        Layer::ColourSignificance s = (*i)->getLayerColourSignificance();
        bool light = (*i)->hasLightBackground();

        if (int(s) > int(maxSignificance)) {
            maxSignificance = s;
            mostSignificantHasDarkBackground = !light;
        } else if (s == maxSignificance && !light) {
            mostSignificantHasDarkBackground = true;
        }
    }

    if (int(maxSignificance) >= int(Layer::ColourAndBackgroundSignificant)) {
        return !mostSignificantHasDarkBackground;
    } else {
        return !darkPalette;
    }
}

QColor
View::getBackground() const
{
    bool light = hasLightBackground();

    QColor widgetbg = palette().window().color();
    bool widgetLight =
        (widgetbg.red() + widgetbg.green() + widgetbg.blue()) > 384;

    if (widgetLight == light) {
        if (widgetLight) {
            return widgetbg.light();
        } else {
            return widgetbg.dark();
        }
    }
    else if (light) return Qt::white;
    else return Qt::black;
}

QColor
View::getForeground() const
{
    bool light = hasLightBackground();

    QColor widgetfg = palette().text().color();
    bool widgetLight =
        (widgetfg.red() + widgetfg.green() + widgetfg.blue()) > 384;

    if (widgetLight != light) return widgetfg;
    else if (light) return Qt::black;
    else return Qt::white;
}

View::LayerProgressBar::LayerProgressBar(QWidget *parent) :
    QProgressBar(parent)
{
    QFont f(font());
    f.setPointSize(f.pointSize() * 8 / 10);
    setFont(f);
}

void
View::addLayer(Layer *layer)
{
    delete m_cache;
    m_cache = 0;

    SingleColourLayer *scl = dynamic_cast<SingleColourLayer *>(layer);
    if (scl) scl->setDefaultColourFor(this);

    m_layers.push_back(layer);

    m_progressBars[layer] = new LayerProgressBar(this);
    m_progressBars[layer]->setMinimum(0);
    m_progressBars[layer]->setMaximum(100);
    m_progressBars[layer]->setMinimumWidth(80);
    m_progressBars[layer]->hide();
    
    connect(layer, SIGNAL(layerParametersChanged()),
	    this,    SLOT(layerParametersChanged()));
    connect(layer, SIGNAL(layerParameterRangesChanged()),
	    this,    SLOT(layerParameterRangesChanged()));
    connect(layer, SIGNAL(layerMeasurementRectsChanged()),
	    this,    SLOT(layerMeasurementRectsChanged()));
    connect(layer, SIGNAL(layerNameChanged()),
	    this,    SLOT(layerNameChanged()));
    connect(layer, SIGNAL(modelChanged()),
	    this,    SLOT(modelChanged()));
    connect(layer, SIGNAL(modelCompletionChanged()),
	    this,    SLOT(modelCompletionChanged()));
    connect(layer, SIGNAL(modelChanged(size_t, size_t)),
	    this,    SLOT(modelChanged(size_t, size_t)));
    connect(layer, SIGNAL(modelReplaced()),
	    this,    SLOT(modelReplaced()));

    update();

    emit propertyContainerAdded(layer);
}

void
View::removeLayer(Layer *layer)
{
    if (m_deleting) {
	return;
    }

    delete m_cache;
    m_cache = 0;

    for (LayerList::iterator i = m_layers.begin(); i != m_layers.end(); ++i) {
	if (*i == layer) {
	    m_layers.erase(i);
	    if (m_progressBars.find(layer) != m_progressBars.end()) {
		delete m_progressBars[layer];
		m_progressBars.erase(layer);
	    }
	    break;
	}
    }
    
    disconnect(layer, SIGNAL(layerParametersChanged()),
               this,    SLOT(layerParametersChanged()));
    disconnect(layer, SIGNAL(layerParameterRangesChanged()),
               this,    SLOT(layerParameterRangesChanged()));
    disconnect(layer, SIGNAL(layerNameChanged()),
               this,    SLOT(layerNameChanged()));
    disconnect(layer, SIGNAL(modelChanged()),
               this,    SLOT(modelChanged()));
    disconnect(layer, SIGNAL(modelCompletionChanged()),
               this,    SLOT(modelCompletionChanged()));
    disconnect(layer, SIGNAL(modelChanged(size_t, size_t)),
               this,    SLOT(modelChanged(size_t, size_t)));
    disconnect(layer, SIGNAL(modelReplaced()),
               this,    SLOT(modelReplaced()));

    update();

    emit propertyContainerRemoved(layer);
}

Layer *
View::getSelectedLayer()
{
    if (m_haveSelectedLayer && !m_layers.empty()) {
	return getLayer(getLayerCount() - 1);
    } else {
	return 0;
    }
}

const Layer *
View::getSelectedLayer() const
{
    return const_cast<const Layer *>(const_cast<View *>(this)->getSelectedLayer());
}

void
View::setViewManager(ViewManager *manager)
{
    if (m_manager) {
	m_manager->disconnect(this, SLOT(globalCentreFrameChanged(unsigned long)));
	m_manager->disconnect(this, SLOT(viewCentreFrameChanged(View *, unsigned long)));
	m_manager->disconnect(this, SLOT(viewManagerPlaybackFrameChanged(unsigned long)));
	m_manager->disconnect(this, SLOT(viewZoomLevelChanged(View *, unsigned long, bool)));
        m_manager->disconnect(this, SLOT(toolModeChanged()));
        m_manager->disconnect(this, SLOT(selectionChanged()));
        m_manager->disconnect(this, SLOT(overlayModeChanged()));
        m_manager->disconnect(this, SLOT(zoomWheelsEnabledChanged()));
        disconnect(m_manager, SLOT(viewCentreFrameChanged(unsigned long, bool, PlaybackFollowMode)));
	disconnect(m_manager, SLOT(zoomLevelChanged(unsigned long, bool)));
    }

    m_manager = manager;

    connect(m_manager, SIGNAL(globalCentreFrameChanged(unsigned long)),
	    this, SLOT(globalCentreFrameChanged(unsigned long)));
    connect(m_manager, SIGNAL(viewCentreFrameChanged(View *, unsigned long)),
	    this, SLOT(viewCentreFrameChanged(View *, unsigned long)));
    connect(m_manager, SIGNAL(playbackFrameChanged(unsigned long)),
	    this, SLOT(viewManagerPlaybackFrameChanged(unsigned long)));

    connect(m_manager, SIGNAL(viewZoomLevelChanged(View *, unsigned long, bool)),
	    this, SLOT(viewZoomLevelChanged(View *, unsigned long, bool)));

    connect(m_manager, SIGNAL(toolModeChanged()),
	    this, SLOT(toolModeChanged()));
    connect(m_manager, SIGNAL(selectionChanged()),
	    this, SLOT(selectionChanged()));
    connect(m_manager, SIGNAL(inProgressSelectionChanged()),
	    this, SLOT(selectionChanged()));
    connect(m_manager, SIGNAL(overlayModeChanged()),
            this, SLOT(overlayModeChanged()));
    connect(m_manager, SIGNAL(zoomWheelsEnabledChanged()),
            this, SLOT(zoomWheelsEnabledChanged()));

    connect(this, SIGNAL(centreFrameChanged(unsigned long, bool,
                                            PlaybackFollowMode)),
            m_manager, SLOT(viewCentreFrameChanged(unsigned long, bool,
                                                   PlaybackFollowMode)));

    connect(this, SIGNAL(zoomLevelChanged(unsigned long, bool)),
	    m_manager, SLOT(viewZoomLevelChanged(unsigned long, bool)));

    if (m_followPlay != PlaybackIgnore) {
//        std::cerr << "View::setViewManager: setting centre frame to playback frame: " << m_manager->getPlaybackFrame() << std::endl;
        setCentreFrame(m_manager->getPlaybackFrame(), false);
    } else if (m_followPan) {
//        std::cerr << "View::setViewManager: setting centre frame to global centre frame: " << m_manager->getGlobalCentreFrame() << std::endl;
        setCentreFrame(m_manager->getGlobalCentreFrame(), false);
    }
    if (m_followZoom) setZoomLevel(m_manager->getGlobalZoom());

    toolModeChanged();
}

void
View::setFollowGlobalPan(bool f)
{
    m_followPan = f;
    emit propertyContainerPropertyChanged(m_propertyContainer);
}

void
View::setFollowGlobalZoom(bool f)
{
    m_followZoom = f;
    emit propertyContainerPropertyChanged(m_propertyContainer);
}

void
View::drawVisibleText(QPainter &paint, int x, int y, QString text, TextStyle style) const
{
    if (style == OutlinedText) {

        paint.save();

        QColor penColour, surroundColour;

        penColour = getForeground();
        surroundColour = getBackground();

	paint.setPen(surroundColour);

	for (int dx = -1; dx <= 1; ++dx) {
	    for (int dy = -1; dy <= 1; ++dy) {
		if (!(dx || dy)) continue;
		paint.drawText(x + dx, y + dy, text);
	    }
	}

	paint.setPen(penColour);

	paint.drawText(x, y, text);

        paint.restore();

    } else {

	std::cerr << "ERROR: View::drawVisibleText: Boxed style not yet implemented!" << std::endl;
    }
}

void
View::setPlaybackFollow(PlaybackFollowMode m)
{
    m_followPlay = m;
    emit propertyContainerPropertyChanged(m_propertyContainer);
}

void
View::modelChanged()
{
    QObject *obj = sender();

#ifdef DEBUG_VIEW_WIDGET_PAINT
    std::cerr << "View(" << this << ")::modelChanged()" << std::endl;
#endif
    
    // If the model that has changed is not used by any of the cached
    // layers, we won't need to recreate the cache
    
    bool recreate = false;

    bool discard;
    LayerList scrollables = getScrollableBackLayers(false, discard);
    for (LayerList::const_iterator i = scrollables.begin();
	 i != scrollables.end(); ++i) {
	if (*i == obj || (*i)->getModel() == obj) {
	    recreate = true;
	    break;
	}
    }

    if (recreate) {
	delete m_cache;
	m_cache = 0;
    }

    checkProgress(obj);

    update();
}

void
View::modelChanged(size_t startFrame, size_t endFrame)
{
    QObject *obj = sender();

    long myStartFrame = getStartFrame();
    size_t myEndFrame = getEndFrame();

#ifdef DEBUG_VIEW_WIDGET_PAINT
    std::cerr << "View(" << this << ")::modelChanged(" << startFrame << "," << endFrame << ") [me " << myStartFrame << "," << myEndFrame << "]" << std::endl;
#endif

    if (myStartFrame > 0 && endFrame < size_t(myStartFrame)) {
	checkProgress(obj);
	return;
    }
    if (startFrame > myEndFrame) {
	checkProgress(obj);
	return;
    }

    // If the model that has changed is not used by any of the cached
    // layers, we won't need to recreate the cache
    
    bool recreate = false;

    bool discard;
    LayerList scrollables = getScrollableBackLayers(false, discard);
    for (LayerList::const_iterator i = scrollables.begin();
	 i != scrollables.end(); ++i) {
	if (*i == obj || (*i)->getModel() == obj) {
	    recreate = true;
	    break;
	}
    }

    if (recreate) {
	delete m_cache;
	m_cache = 0;
    }

    if (long(startFrame) < myStartFrame) startFrame = myStartFrame;
    if (endFrame > myEndFrame) endFrame = myEndFrame;

    checkProgress(obj);

    update();
}    

void
View::modelCompletionChanged()
{
    std::cerr << "View(" << this << ")::modelCompletionChanged()" << std::endl;

    QObject *obj = sender();
    checkProgress(obj);
}

void
View::modelReplaced()
{
#ifdef DEBUG_VIEW_WIDGET_PAINT
    std::cerr << "View(" << this << ")::modelReplaced()" << std::endl;
#endif
    delete m_cache;
    m_cache = 0;

    update();
}

void
View::layerParametersChanged()
{
    Layer *layer = dynamic_cast<Layer *>(sender());

#ifdef DEBUG_VIEW_WIDGET_PAINT
    std::cerr << "View::layerParametersChanged()" << std::endl;
#endif

    delete m_cache;
    m_cache = 0;
    update();

    if (layer) {
	emit propertyContainerPropertyChanged(layer);
    }
}

void
View::layerParameterRangesChanged()
{
    Layer *layer = dynamic_cast<Layer *>(sender());
    if (layer) emit propertyContainerPropertyRangeChanged(layer);
}

void
View::layerMeasurementRectsChanged()
{
    Layer *layer = dynamic_cast<Layer *>(sender());
    if (layer) update();
}

void
View::layerNameChanged()
{
    Layer *layer = dynamic_cast<Layer *>(sender());
    if (layer) emit propertyContainerNameChanged(layer);
}

void
View::globalCentreFrameChanged(unsigned long f)
{
    if (m_followPan) {
        setCentreFrame(f, false);
    }
}

void
View::viewCentreFrameChanged(View *, unsigned long )
{
    // We do nothing with this, but a subclass might
}

void
View::viewManagerPlaybackFrameChanged(unsigned long f)
{
    if (m_manager) {
	if (sender() != m_manager) return;
    }

    f = getAlignedPlaybackFrame();

    if (m_playPointerFrame == f) return;
    bool visible = (getXForFrame(m_playPointerFrame) != getXForFrame(f));
    size_t oldPlayPointerFrame = m_playPointerFrame;
    m_playPointerFrame = f;
    if (!visible) return;

    switch (m_followPlay) {

    case PlaybackScrollContinuous:
	if (QApplication::mouseButtons() == Qt::NoButton) {
	    setCentreFrame(f, false);
	}
	break;

    case PlaybackScrollPage:
    { 
	int xold = getXForFrame(oldPlayPointerFrame);
	update(xold - 1, 0, 3, height());

	long w = getEndFrame() - getStartFrame();
	w -= w/5;
	long sf = (f / w) * w - w/8;

	if (m_manager &&
	    m_manager->isPlaying() &&
	    m_manager->getPlaySelectionMode()) {
	    MultiSelection::SelectionList selections = m_manager->getSelections();
	    if (!selections.empty()) {
		size_t selectionStart = selections.begin()->getStartFrame();
		if (sf < long(selectionStart) - w / 10) {
		    sf = long(selectionStart) - w / 10;
		}
	    }
	}

#ifdef DEBUG_VIEW_WIDGET_PAINT
	std::cerr << "PlaybackScrollPage: f = " << f << ", sf = " << sf << ", start frame "
		  << getStartFrame() << std::endl;
#endif

	// We don't consider scrolling unless the pointer is outside
	// the clearly visible range already

	int xnew = getXForFrame(m_playPointerFrame);

#ifdef DEBUG_VIEW_WIDGET_PAINT
	std::cerr << "xnew = " << xnew << ", width = " << width() << std::endl;
#endif

	if (xnew < width()/8 || xnew > (width()*7)/8) {
	    if (QApplication::mouseButtons() == Qt::NoButton) {
		long offset = getFrameForX(width()/2) - getStartFrame();
		long newCentre = sf + offset;
		bool changed = setCentreFrame(newCentre, false);
		if (changed) {
		    xold = getXForFrame(oldPlayPointerFrame);
		    update(xold - 1, 0, 3, height());
		}
	    }
	}

	update(xnew - 1, 0, 3, height());

	break;
    }

    case PlaybackIgnore:
	if (long(f) >= getStartFrame() && f < getEndFrame()) {
	    update();
	}
	break;
    }
}

void
View::viewZoomLevelChanged(View *p, unsigned long z, bool locked)
{
#ifdef DEBUG_VIEW_WIDGET_PAINT
    std::cerr  << "View[" << this << "]: viewZoomLevelChanged(" << p << ", " << z << ", " << locked << ")" << std::endl;
#endif
    if (m_followZoom && p != this && locked) {
        setZoomLevel(z);
    }
}

void
View::selectionChanged()
{
    if (m_selectionCached) {
	delete m_cache;
	m_cache = 0;
	m_selectionCached = false;
    }
    update();
}

size_t
View::getFirstVisibleFrame() const
{
    long f0 = getStartFrame();
    size_t f = getModelsStartFrame();
    if (f0 < 0 || f0 < long(f)) return f;
    return f0;
}

size_t 
View::getLastVisibleFrame() const
{
    size_t f0 = getEndFrame();
    size_t f = getModelsEndFrame();
    if (f0 > f) return f;
    return f0;
}

size_t
View::getModelsStartFrame() const
{
    bool first = true;
    size_t startFrame = 0;

    for (LayerList::const_iterator i = m_layers.begin(); i != m_layers.end(); ++i) {

	if ((*i)->getModel() && (*i)->getModel()->isOK()) {

	    size_t thisStartFrame = (*i)->getModel()->getStartFrame();

	    if (first || thisStartFrame < startFrame) {
		startFrame = thisStartFrame;
	    }
	    first = false;
	}
    }
    return startFrame;
}

size_t
View::getModelsEndFrame() const
{
    bool first = true;
    size_t endFrame = 0;

    for (LayerList::const_iterator i = m_layers.begin(); i != m_layers.end(); ++i) {

	if ((*i)->getModel() && (*i)->getModel()->isOK()) {

	    size_t thisEndFrame = (*i)->getModel()->getEndFrame();

	    if (first || thisEndFrame > endFrame) {
		endFrame = thisEndFrame;
	    }
	    first = false;
	}
    }

    if (first) return getModelsStartFrame();
    return endFrame;
}

int
View::getModelsSampleRate() const
{
    //!!! Just go for the first, for now.  If we were supporting
    // multiple samplerates, we'd probably want to do frame/time
    // conversion in the model

    //!!! nah, this wants to always return the sr of the main model!

    for (LayerList::const_iterator i = m_layers.begin(); i != m_layers.end(); ++i) {
	if ((*i)->getModel() && (*i)->getModel()->isOK()) {
	    return (*i)->getModel()->getSampleRate();
	}
    }
    return 0;
}

View::ModelSet
View::getModels()
{
    ModelSet models;

    for (int i = 0; i < getLayerCount(); ++i) {

        Layer *layer = getLayer(i);

        if (dynamic_cast<TimeRulerLayer *>(layer)) {
            continue;
        }

        if (layer && layer->getModel()) {
            Model *model = layer->getModel();
            models.insert(model);
        }
    }

    return models;
}

int
View::getAlignedPlaybackFrame() const
{
    if (!m_manager) return 0;
    if (!m_manager->getAlignMode() ||
        !m_manager->getPlaybackModel()) {
        return m_manager->getPlaybackFrame();
    }

    RangeSummarisableTimeValueModel *waveformModel = 0;
    for (LayerList::const_iterator i = m_layers.begin(); i != m_layers.end(); ++i) {

        if (!*i) continue;
        if (dynamic_cast<TimeRulerLayer *>(*i)) continue;

        Model *model = (*i)->getModel();
        if (!model) continue;

        waveformModel = dynamic_cast<RangeSummarisableTimeValueModel *>(model);
        if (!waveformModel) {
            waveformModel = dynamic_cast<RangeSummarisableTimeValueModel *>
                (model->getSourceModel());
        }

        if (waveformModel) break;
    }

    int pf = m_manager->getPlaybackFrame();

    if (!waveformModel) return pf;

    RangeSummarisableTimeValueModel *pm =
        dynamic_cast<RangeSummarisableTimeValueModel *>
        (m_manager->getPlaybackModel());

//    std::cerr << "View[" << this << "]::getAlignedPlaybackFrame: pf = " << pf;

    if (pm) {
        pf = pm->alignFromReference(pf);
//        std::cerr << " -> " << pf;
    }

    int af = waveformModel->alignToReference(pf);

//    std::cerr << ", aligned = " << af << std::endl;
    return af;
}

bool
View::areLayersScrollable() const
{
    // True iff all views are scrollable
    for (LayerList::const_iterator i = m_layers.begin(); i != m_layers.end(); ++i) {
	if (!(*i)->isLayerScrollable(this)) return false;
    }
    return true;
}

View::LayerList
View::getScrollableBackLayers(bool testChanged, bool &changed) const
{
    changed = false;

    // We want a list of all the scrollable layers that are behind the
    // backmost non-scrollable layer.

    LayerList scrollables;
    bool metUnscrollable = false;

    for (LayerList::const_iterator i = m_layers.begin(); i != m_layers.end(); ++i) {
//        std::cerr << "View::getScrollableBackLayers: calling isLayerDormant on layer " << *i << std::endl;
//        std::cerr << "(name is " << (*i)->objectName().toStdString() << ")"
//                  << std::endl;
//        std::cerr << "View::getScrollableBackLayers: I am " << this << std::endl;
	if ((*i)->isLayerDormant(this)) continue;
	if ((*i)->isLayerOpaque()) {
	    // You can't see anything behind an opaque layer!
	    scrollables.clear();
            if (metUnscrollable) break;
	}
	if (!metUnscrollable && (*i)->isLayerScrollable(this)) {
            scrollables.push_back(*i);
        } else {
            metUnscrollable = true;
        }
    }

    if (testChanged && scrollables != m_lastScrollableBackLayers) {
	m_lastScrollableBackLayers = scrollables;
	changed = true;
    }
    return scrollables;
}

View::LayerList
View::getNonScrollableFrontLayers(bool testChanged, bool &changed) const
{
    changed = false;
    LayerList nonScrollables;

    // Everything in front of the first non-scrollable from the back
    // should also be considered non-scrollable

    bool started = false;

    for (LayerList::const_iterator i = m_layers.begin(); i != m_layers.end(); ++i) {
	if ((*i)->isLayerDormant(this)) continue;
	if (!started && (*i)->isLayerScrollable(this)) {
	    continue;
	}
	started = true;
	if ((*i)->isLayerOpaque()) {
	    // You can't see anything behind an opaque layer!
	    nonScrollables.clear();
	}
	nonScrollables.push_back(*i);
    }

    if (testChanged && nonScrollables != m_lastNonScrollableBackLayers) {
	m_lastNonScrollableBackLayers = nonScrollables;
	changed = true;
    }

    return nonScrollables;
}

size_t
View::getZoomConstraintBlockSize(size_t blockSize,
				 ZoomConstraint::RoundingDirection dir)
    const
{
    size_t candidate = blockSize;
    bool haveCandidate = false;

    PowerOfSqrtTwoZoomConstraint defaultZoomConstraint;

    for (LayerList::const_iterator i = m_layers.begin(); i != m_layers.end(); ++i) {

	const ZoomConstraint *zoomConstraint = (*i)->getZoomConstraint();
	if (!zoomConstraint) zoomConstraint = &defaultZoomConstraint;

	size_t thisBlockSize =
	    zoomConstraint->getNearestBlockSize(blockSize, dir);

	// Go for the block size that's furthest from the one
	// passed in.  Most of the time, that's what we want.
	if (!haveCandidate ||
	    (thisBlockSize > blockSize && thisBlockSize > candidate) ||
	    (thisBlockSize < blockSize && thisBlockSize < candidate)) {
	    candidate = thisBlockSize;
	    haveCandidate = true;
	}
    }

    return candidate;
}

bool
View::areLayerColoursSignificant() const
{
    for (LayerList::const_iterator i = m_layers.begin(); i != m_layers.end(); ++i) {
	if ((*i)->getLayerColourSignificance() ==
            Layer::ColourHasMeaningfulValue) return true;
        if ((*i)->isLayerOpaque()) break;
    }
    return false;
}

bool
View::hasTopLayerTimeXAxis() const
{
    LayerList::const_iterator i = m_layers.end();
    if (i == m_layers.begin()) return false;
    --i;
    return (*i)->hasTimeXAxis();
}

void
View::zoom(bool in)
{
    int newZoomLevel = m_zoomLevel;

    if (in) {
	newZoomLevel = getZoomConstraintBlockSize(newZoomLevel - 1, 
						  ZoomConstraint::RoundDown);
    } else {
	newZoomLevel = getZoomConstraintBlockSize(newZoomLevel + 1,
						  ZoomConstraint::RoundUp);
    }

    if (newZoomLevel != m_zoomLevel) {
	setZoomLevel(newZoomLevel);
    }
}

void
View::scroll(bool right, bool lots)
{
    long delta;
    if (lots) {
	delta = (getEndFrame() - getStartFrame()) / 2;
    } else {
	delta = (getEndFrame() - getStartFrame()) / 20;
    }
    if (right) delta = -delta;

    if (int(m_centreFrame) < delta) {
	setCentreFrame(0);
    } else if (int(m_centreFrame) - delta >= int(getModelsEndFrame())) {
	setCentreFrame(getModelsEndFrame());
    } else {
	setCentreFrame(m_centreFrame - delta);
    }
}

void
View::checkProgress(void *object)
{
    if (!m_showProgress) return;

    int ph = height();

    for (ProgressMap::const_iterator i = m_progressBars.begin();
	 i != m_progressBars.end(); ++i) {

	if (i->first == object) {

	    int completion = i->first->getCompletion(this);
            QString text = i->first->getPropertyContainerName();

            if (completion >= 100) {

                //!!!
                Model *model = i->first->getModel();
                RangeSummarisableTimeValueModel *wfm = 
                    dynamic_cast<RangeSummarisableTimeValueModel *>(model);
                if (wfm) {
                    completion = wfm->getAlignmentCompletion();
                    if (completion < 100) {
                        text = tr("Alignment");
                    }
                }
            }

	    if (completion >= 100) {

		i->second->hide();

	    } else {

		i->second->setText(text);

		i->second->setValue(completion);
		i->second->move(0, ph - i->second->height());

		i->second->show();
		i->second->update();

		ph -= i->second->height();
	    }
	} else {
	    if (i->second->isVisible()) {
		ph -= i->second->height();
	    }
	}
    }
}

void
View::paintEvent(QPaintEvent *e)
{
//    Profiler prof("View::paintEvent", false);
//    std::cerr << "View::paintEvent: centre frame is " << m_centreFrame << std::endl;

    if (m_layers.empty()) {
	QFrame::paintEvent(e);
	return;
    }

    // ensure our constraints are met

/*!!! Should we do this only if we have layers that can't support other
  zoom levels?

    m_zoomLevel = getZoomConstraintBlockSize(m_zoomLevel,
					     ZoomConstraint::RoundUp);
*/

    QPainter paint;
    bool repaintCache = false;
    bool paintedCacheRect = false;

    QRect cacheRect(rect());

    if (e) {
	cacheRect &= e->rect();
#ifdef DEBUG_VIEW_WIDGET_PAINT
	std::cerr << "paint rect " << cacheRect.width() << "x" << cacheRect.height()
		  << ", my rect " << width() << "x" << height() << std::endl;
#endif
    }

    QRect nonCacheRect(cacheRect);

    // If not all layers are scrollable, but some of the back layers
    // are, we should store only those in the cache.

    bool layersChanged = false;
    LayerList scrollables = getScrollableBackLayers(true, layersChanged);
    LayerList nonScrollables = getNonScrollableFrontLayers(true, layersChanged);
    bool selectionCacheable = nonScrollables.empty();
    bool haveSelections = m_manager && !m_manager->getSelections().empty();
    bool selectionDrawn = false;

    // If all the non-scrollable layers are non-opaque, then we draw
    // the selection rectangle behind them and cache it.  If any are
    // opaque, however, we can't cache.
    //
    if (!selectionCacheable) {
	selectionCacheable = true;
	for (LayerList::const_iterator i = nonScrollables.begin();
	     i != nonScrollables.end(); ++i) {
	    if ((*i)->isLayerOpaque()) {
		selectionCacheable = false;
		break;
	    }
	}
    }

    if (selectionCacheable) {
	QPoint localPos;
	bool closeToLeft, closeToRight;
	if (shouldIlluminateLocalSelection(localPos, closeToLeft, closeToRight)) {
	    selectionCacheable = false;
	}
    }

#ifdef DEBUG_VIEW_WIDGET_PAINT
    std::cerr << "View(" << this << ")::paintEvent: have " << scrollables.size()
	      << " scrollable back layers and " << nonScrollables.size()
	      << " non-scrollable front layers" << std::endl;
    std::cerr << "haveSelections " << haveSelections << ", selectionCacheable "
	      << selectionCacheable << ", m_selectionCached " << m_selectionCached << std::endl;
#endif

    if (layersChanged || scrollables.empty() ||
	(haveSelections && (selectionCacheable != m_selectionCached))) {
	delete m_cache;
	m_cache = 0;
	m_selectionCached = false;
    }

    if (!scrollables.empty()) {

#ifdef DEBUG_VIEW_WIDGET_PAINT
        std::cerr << "View(" << this << "): cache " << m_cache << ", cache zoom "
                  << m_cacheZoomLevel << ", zoom " << m_zoomLevel << std::endl;
#endif

	if (!m_cache ||
	    m_cacheZoomLevel != m_zoomLevel ||
	    width() != m_cache->width() ||
	    height() != m_cache->height()) {

	    // cache is not valid

	    if (cacheRect.width() < width()/10) {
		delete m_cache;
                m_cache = 0;
#ifdef DEBUG_VIEW_WIDGET_PAINT
		std::cerr << "View(" << this << ")::paintEvent: small repaint, not bothering to recreate cache" << std::endl;
#endif
	    } else {
		delete m_cache;
		m_cache = new QPixmap(width(), height());
#ifdef DEBUG_VIEW_WIDGET_PAINT
		std::cerr << "View(" << this << ")::paintEvent: recreated cache" << std::endl;
#endif
		cacheRect = rect();
		repaintCache = true;
	    }

	} else if (m_cacheCentreFrame != m_centreFrame) {

	    long dx =
		getXForFrame(m_cacheCentreFrame) -
		getXForFrame(m_centreFrame);

	    if (dx > -width() && dx < width()) {
#if defined(Q_WS_WIN32) || defined(Q_WS_MAC)
		// Copying a pixmap to itself doesn't work properly on Windows
		// or Mac (it only works when moving in one direction)
		static QPixmap *tmpPixmap = 0;
		if (!tmpPixmap ||
		    tmpPixmap->width() != width() ||
		    tmpPixmap->height() != height()) {
		    delete tmpPixmap;
		    tmpPixmap = new QPixmap(width(), height());
		}
		paint.begin(tmpPixmap);
		paint.drawPixmap(0, 0, *m_cache);
		paint.end();
		paint.begin(m_cache);
		paint.drawPixmap(dx, 0, *tmpPixmap);
		paint.end();
#else
		// But it seems to be fine on X11
		paint.begin(m_cache);
		paint.drawPixmap(dx, 0, *m_cache);
		paint.end();
#endif

		if (dx < 0) {
		    cacheRect = QRect(width() + dx, 0, -dx, height());
		} else {
		    cacheRect = QRect(0, 0, dx, height());
		}
#ifdef DEBUG_VIEW_WIDGET_PAINT
		std::cerr << "View(" << this << ")::paintEvent: scrolled cache by " << dx << std::endl;
#endif
	    } else {
		cacheRect = rect();
#ifdef DEBUG_VIEW_WIDGET_PAINT
		std::cerr << "View(" << this << ")::paintEvent: scrolling too far" << std::endl;
#endif
	    }
	    repaintCache = true;

	} else {
#ifdef DEBUG_VIEW_WIDGET_PAINT
	    std::cerr << "View(" << this << ")::paintEvent: cache is good" << std::endl;
#endif
	    paint.begin(this);
	    paint.drawPixmap(cacheRect, *m_cache, cacheRect);
	    paint.end();
	    QFrame::paintEvent(e);
	    paintedCacheRect = true;
	}

	m_cacheCentreFrame = m_centreFrame;
	m_cacheZoomLevel = m_zoomLevel;
    }

#ifdef DEBUG_VIEW_WIDGET_PAINT
//    std::cerr << "View(" << this << ")::paintEvent: cacheRect " << cacheRect << ", nonCacheRect " << (nonCacheRect | cacheRect) << ", repaintCache " << repaintCache << ", paintedCacheRect " << paintedCacheRect << std::endl;
#endif

    // Scrollable (cacheable) items first

    if (!paintedCacheRect) {

	if (repaintCache) paint.begin(m_cache);
	else paint.begin(this);

	paint.setClipRect(cacheRect);

        paint.setPen(getBackground());
        paint.setBrush(getBackground());
	paint.drawRect(cacheRect);

	paint.setPen(getForeground());
	paint.setBrush(Qt::NoBrush);
	
	for (LayerList::iterator i = scrollables.begin(); i != scrollables.end(); ++i) {
	    paint.setRenderHint(QPainter::Antialiasing, false);
	    paint.save();
	    (*i)->paint(this, paint, cacheRect);
	    paint.restore();
	}

	if (haveSelections && selectionCacheable) {
	    drawSelections(paint);
	    m_selectionCached = repaintCache;
	    selectionDrawn = true;
	}
	
	paint.end();

	if (repaintCache) {
	    cacheRect |= (e ? e->rect() : rect());
	    paint.begin(this);
	    paint.drawPixmap(cacheRect, *m_cache, cacheRect);
	    paint.end();
	}
    }

    // Now non-cacheable items.  We always need to redraw the
    // non-cacheable items across at least the area we drew of the
    // cacheable items.

    nonCacheRect |= cacheRect;

    paint.begin(this);
    paint.setClipRect(nonCacheRect);

    if (scrollables.empty()) {
        paint.setPen(getBackground());
        paint.setBrush(getBackground());
	paint.drawRect(nonCacheRect);
    }
	
    paint.setPen(getForeground());
    paint.setBrush(Qt::NoBrush);
	
    for (LayerList::iterator i = nonScrollables.begin(); i != nonScrollables.end(); ++i) {
//        Profiler profiler2("View::paintEvent non-cacheable");
	(*i)->paint(this, paint, nonCacheRect);
    }
	
    paint.end();

    paint.begin(this);
    if (e) paint.setClipRect(e->rect());
    if (!m_selectionCached) {
	drawSelections(paint);
    }
    paint.end();

    bool showPlayPointer = true;
    if (m_followPlay == PlaybackScrollContinuous) {
        showPlayPointer = false;
    } else if (long(m_playPointerFrame) <= getStartFrame() ||
               m_playPointerFrame >= getEndFrame()) {
        showPlayPointer = false;
    } else if (m_manager && !m_manager->isPlaying()) {
        if (m_playPointerFrame == getCentreFrame() &&
            m_followPlay != PlaybackIgnore) {
            showPlayPointer = false;
        }
    }

    if (showPlayPointer) {

	paint.begin(this);

        int playx = getXForFrame(m_playPointerFrame);
        
        paint.setPen(getForeground());
        paint.drawLine(playx - 1, 0, playx - 1, height() - 1);
        paint.drawLine(playx + 1, 0, playx + 1, height() - 1);
        paint.drawPoint(playx, 0);
        paint.drawPoint(playx, height() - 1);
        paint.setPen(getBackground());
        paint.drawLine(playx, 1, playx, height() - 2);

	paint.end();
    }

    QFrame::paintEvent(e);
}

void
View::drawSelections(QPainter &paint)
{
    if (!hasTopLayerTimeXAxis()) return;

    MultiSelection::SelectionList selections;

    if (m_manager) {
	selections = m_manager->getSelections();
	if (m_manager->haveInProgressSelection()) {
	    bool exclusive;
	    Selection inProgressSelection =
		m_manager->getInProgressSelection(exclusive);
	    if (exclusive) selections.clear();
	    selections.insert(inProgressSelection);
	}
    }

    paint.save();

    bool translucent = !areLayerColoursSignificant();

    if (translucent) {
        paint.setBrush(QColor(150, 150, 255, 80));
    } else {
        paint.setBrush(Qt::NoBrush);
    }

    int sampleRate = getModelsSampleRate();

    QPoint localPos;
    long illuminateFrame = -1;
    bool closeToLeft, closeToRight;

    if (shouldIlluminateLocalSelection(localPos, closeToLeft, closeToRight)) {
	illuminateFrame = getFrameForX(localPos.x());
    }

    const QFontMetrics &metrics = paint.fontMetrics();

    for (MultiSelection::SelectionList::iterator i = selections.begin();
	 i != selections.end(); ++i) {

	int p0 = getXForFrame(i->getStartFrame());
	int p1 = getXForFrame(i->getEndFrame());

	if (p1 < 0 || p0 > width()) continue;

#ifdef DEBUG_VIEW_WIDGET_PAINT
	std::cerr << "View::drawSelections: " << p0 << ",-1 [" << (p1-p0) << "x" << (height()+1) << "]" << std::endl;
#endif

	bool illuminateThis =
	    (illuminateFrame >= 0 && i->contains(illuminateFrame));

	paint.setPen(QColor(150, 150, 255));

        if (translucent && shouldLabelSelections()) {
            paint.drawRect(p0, -1, p1 - p0, height() + 1);
        } else {
            // Make the top & bottom lines of the box visible if we
            // are lacking some of the other visual cues.  There's no
            // particular logic to this, it's just a question of what
            // I happen to think looks nice.
            paint.drawRect(p0, 0, p1 - p0, height() - 1);
        }

	if (illuminateThis) {
	    paint.save();
            paint.setPen(QPen(getForeground(), 2));
	    if (closeToLeft) {
		paint.drawLine(p0, 1, p1, 1);
		paint.drawLine(p0, 0, p0, height());
		paint.drawLine(p0, height() - 1, p1, height() - 1);
	    } else if (closeToRight) {
		paint.drawLine(p0, 1, p1, 1);
		paint.drawLine(p1, 0, p1, height());
		paint.drawLine(p0, height() - 1, p1, height() - 1);
	    } else {
		paint.setBrush(Qt::NoBrush);
		paint.drawRect(p0, 1, p1 - p0, height() - 2);
	    }
	    paint.restore();
	}

	if (sampleRate && shouldLabelSelections() && m_manager &&
            m_manager->shouldShowSelectionExtents()) {
	    
	    QString startText = QString("%1 / %2")
		.arg(QString::fromStdString
		     (RealTime::frame2RealTime
		      (i->getStartFrame(), sampleRate).toText(true)))
		.arg(i->getStartFrame());
	    
	    QString endText = QString(" %1 / %2")
		.arg(QString::fromStdString
		     (RealTime::frame2RealTime
		      (i->getEndFrame(), sampleRate).toText(true)))
		.arg(i->getEndFrame());
	    
	    QString durationText = QString("(%1 / %2) ")
		.arg(QString::fromStdString
		     (RealTime::frame2RealTime
		      (i->getEndFrame() - i->getStartFrame(), sampleRate)
		      .toText(true)))
		.arg(i->getEndFrame() - i->getStartFrame());

	    int sw = metrics.width(startText),
		ew = metrics.width(endText),
		dw = metrics.width(durationText);

	    int sy = metrics.ascent() + metrics.height() + 4;
	    int ey = sy;
	    int dy = sy + metrics.height();

	    int sx = p0 + 2;
	    int ex = sx;
	    int dx = sx;

	    if (sw + ew > (p1 - p0)) {
		ey += metrics.height();
		dy += metrics.height();
	    }

	    if (ew < (p1 - p0)) {
		ex = p1 - 2 - ew;
	    }

	    if (dw < (p1 - p0)) {
		dx = p1 - 2 - dw;
	    }

	    paint.drawText(sx, sy, startText);
	    paint.drawText(ex, ey, endText);
	    paint.drawText(dx, dy, durationText);
	}
    }

    paint.restore();
}

void
View::drawMeasurementRect(QPainter &paint, const Layer *topLayer, QRect r,
                          bool focus) const
{
//    std::cerr << "View::drawMeasurementRect(" << r.x() << "," << r.y() << " "
//              << r.width() << "x" << r.height() << ")" << std::endl;

    if (r.x() + r.width() < 0 || r.x() >= width()) return;

    if (r.width() != 0 || r.height() != 0) {
        paint.save();
        if (focus) {
            paint.setPen(Qt::NoPen);
            QColor brushColour(Qt::black);
            brushColour.setAlpha(hasLightBackground() ? 15 : 40);
            paint.setBrush(brushColour);
            if (r.x() > 0) {
                paint.drawRect(0, 0, r.x(), height());
            }
            if (r.x() + r.width() < width()) {
                paint.drawRect(r.x() + r.width(), 0, width()-r.x()-r.width(), height());
            }
            if (r.y() > 0) {
                paint.drawRect(r.x(), 0, r.width(), r.y());
            }
            if (r.y() + r.height() < height()) {
                paint.drawRect(r.x(), r.y() + r.height(), r.width(), height()-r.y()-r.height());
            }
            paint.setBrush(Qt::NoBrush);
        }
        paint.setPen(Qt::green);
        paint.drawRect(r);
        paint.restore();
    } else {
        paint.save();
        paint.setPen(Qt::green);
        paint.drawPoint(r.x(), r.y());
        paint.restore();
    }

    if (!focus) return;

    paint.save();
    QFont fn = paint.font();
    if (fn.pointSize() > 8) {
        fn.setPointSize(fn.pointSize() - 1);
        paint.setFont(fn);
    }

    int fontHeight = paint.fontMetrics().height();
    int fontAscent = paint.fontMetrics().ascent();

    float v0, v1;
    QString u0, u1;
    bool b0 = false, b1 = false;

    QString axs, ays, bxs, bys, dxs, dys;

    int axx, axy, bxx, bxy, dxx, dxy;
    int aw = 0, bw = 0, dw = 0;
    
    int labelCount = 0;

    if ((b0 = topLayer->getXScaleValue(this, r.x(), v0, u0))) {
        axs = QString("%1 %2").arg(v0).arg(u0);
        if (u0 == "Hz" && Pitch::isFrequencyInMidiRange(v0)) {
            axs = QString("%1 (%2)").arg(axs)
                .arg(Pitch::getPitchLabelForFrequency(v0));
        }
        aw = paint.fontMetrics().width(axs);
        ++labelCount;
    }
        
    if (r.width() > 0) {
        if ((b1 = topLayer->getXScaleValue(this, r.x() + r.width(), v1, u1))) {
            bxs = QString("%1 %2").arg(v1).arg(u1);
            if (u1 == "Hz" && Pitch::isFrequencyInMidiRange(v1)) {
                bxs = QString("%1 (%2)").arg(bxs)
                    .arg(Pitch::getPitchLabelForFrequency(v1));
            }
            bw = paint.fontMetrics().width(bxs);
        }
    }
        
    if (b0 && b1 && v1 != v0 && u0 == u1) {
        dxs = QString("(%1 %2)").arg(fabs(v1 - v0)).arg(u1);
        dw = paint.fontMetrics().width(dxs);
    }
    
    b0 = false;
    b1 = false;

    if ((b0 = topLayer->getYScaleValue(this, r.y(), v0, u0))) {
        ays = QString("%1 %2").arg(v0).arg(u0);
        if (u0 == "Hz" && Pitch::isFrequencyInMidiRange(v0)) {
            ays = QString("%1 (%2)").arg(ays)
                .arg(Pitch::getPitchLabelForFrequency(v0));
        }
        aw = std::max(aw, paint.fontMetrics().width(ays));
        ++labelCount;
    }

    if (r.height() > 0) {
        if ((b1 = topLayer->getYScaleValue(this, r.y() + r.height(), v1, u1))) {
            bys = QString("%1 %2").arg(v1).arg(u1);
            if (u1 == "Hz" && Pitch::isFrequencyInMidiRange(v1)) {
                bys = QString("%1 (%2)").arg(bys)
                    .arg(Pitch::getPitchLabelForFrequency(v1));
            }
            bw = std::max(bw, paint.fontMetrics().width(bys));
        }
    }

    bool bd = false;
    float dy = 0.f;
    QString du;

    if ((bd = topLayer->getYScaleDifference(this, r.y(), r.y() + r.height(),
                                            dy, du)) &&
        dy != 0) {
        if (du != "") {
            dys = QString("(%1 %2)").arg(dy).arg(du);
        } else {
            dys = QString("(%1)").arg(dy);
        }
        dw = std::max(dw, paint.fontMetrics().width(dys));
    }

    int mw = r.width();
    int mh = r.height();

    bool edgeLabelsInside = false;
    bool sizeLabelsInside = false;

    if (mw < std::max(aw, std::max(bw, dw)) + 4) {
        // defaults stand
    } else if (mw < aw + bw + 4) {
        if (mh > fontHeight * labelCount * 3 + 4) {
            edgeLabelsInside = true;
            sizeLabelsInside = true;
        } else if (mh > fontHeight * labelCount * 2 + 4) {
            edgeLabelsInside = true;
        }
    } else if (mw < aw + bw + dw + 4) {
        if (mh > fontHeight * labelCount * 3 + 4) {
            edgeLabelsInside = true;
            sizeLabelsInside = true;
        } else if (mh > fontHeight * labelCount + 4) {
            edgeLabelsInside = true;
        }
    } else {
        if (mh > fontHeight * labelCount + 4) {
            edgeLabelsInside = true;
            sizeLabelsInside = true;
        }
    }

    if (edgeLabelsInside) {

        axx = r.x() + 2;
        axy = r.y() + fontAscent + 2;

        bxx = r.x() + r.width() - bw - 2;
        bxy = r.y() + r.height() - (labelCount-1) * fontHeight - 2;

    } else {

        axx = r.x() - aw - 2;
        axy = r.y() + fontAscent;
        
        bxx = r.x() + r.width() + 2;
        bxy = r.y() + r.height() - (labelCount-1) * fontHeight;
    }

    dxx = r.width()/2 + r.x() - dw/2;

    if (sizeLabelsInside) {

        dxy = r.height()/2 + r.y() - (labelCount * fontHeight)/2 + fontAscent;

    } else {

        dxy = r.y() + r.height() + fontAscent + 2;
    }
    
    if (axs != "") {
        drawVisibleText(paint, axx, axy, axs, OutlinedText);
        axy += fontHeight;
    }
    
    if (ays != "") {
        drawVisibleText(paint, axx, axy, ays, OutlinedText);
        axy += fontHeight;
    }

    if (bxs != "") {
        drawVisibleText(paint, bxx, bxy, bxs, OutlinedText);
        bxy += fontHeight;
    }

    if (bys != "") {
        drawVisibleText(paint, bxx, bxy, bys, OutlinedText);
        bxy += fontHeight;
    }

    if (dxs != "") {
        drawVisibleText(paint, dxx, dxy, dxs, OutlinedText);
        dxy += fontHeight;
    }

    if (dys != "") {
        drawVisibleText(paint, dxx, dxy, dys, OutlinedText);
        dxy += fontHeight;
    }

    paint.restore();
}

bool
View::render(QPainter &paint, int xorigin, size_t f0, size_t f1)
{
    size_t x0 = f0 / m_zoomLevel;
    size_t x1 = f1 / m_zoomLevel;

    size_t w = x1 - x0;

    size_t origCentreFrame = m_centreFrame;

    bool someLayersIncomplete = false;

    for (LayerList::iterator i = m_layers.begin();
         i != m_layers.end(); ++i) {

        int c = (*i)->getCompletion(this);
        if (c < 100) {
            someLayersIncomplete = true;
            break;
        }
    }

    if (someLayersIncomplete) {

        QProgressDialog progress(tr("Waiting for layers to be ready..."),
                                 tr("Cancel"), 0, 100, this);
        
        int layerCompletion = 0;

        while (layerCompletion < 100) {

            for (LayerList::iterator i = m_layers.begin();
                 i != m_layers.end(); ++i) {

                int c = (*i)->getCompletion(this);
                if (i == m_layers.begin() || c < layerCompletion) {
                    layerCompletion = c;
                }
            }

            if (layerCompletion >= 100) break;

            progress.setValue(layerCompletion);
            qApp->processEvents();
            if (progress.wasCanceled()) {
                update();
                return false;
            }

            usleep(50000);
        }
    }

    QProgressDialog progress(tr("Rendering image..."),
                             tr("Cancel"), 0, w / width(), this);

    for (size_t x = 0; x < w; x += width()) {

        progress.setValue(x / width());
        qApp->processEvents();
        if (progress.wasCanceled()) {
            m_centreFrame = origCentreFrame;
            update();
            return false;
        }

        m_centreFrame = f0 + (x + width()/2) * m_zoomLevel;
        
        QRect chunk(0, 0, width(), height());

        paint.setPen(getBackground());
        paint.setBrush(getBackground());

	paint.drawRect(QRect(xorigin + x, 0, width(), height()));

	paint.setPen(getForeground());
	paint.setBrush(Qt::NoBrush);

	for (LayerList::iterator i = m_layers.begin();
             i != m_layers.end(); ++i) {

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

	    paint.save();
            paint.translate(xorigin + x, 0);

            std::cerr << "Centre frame now: " << m_centreFrame << " drawing to " << chunk.x() + x + xorigin << ", " << chunk.width() << std::endl;

	    (*i)->paint(this, paint, chunk);

	    paint.restore();
	}
    }

    m_centreFrame = origCentreFrame;
    update();
    return true;
}

QImage *
View::toNewImage()
{
    size_t f0 = getModelsStartFrame();
    size_t f1 = getModelsEndFrame();

    return toNewImage(f0, f1);
}

QImage *
View::toNewImage(size_t f0, size_t f1)
{
    size_t x0 = f0 / getZoomLevel();
    size_t x1 = f1 / getZoomLevel();
    
    QImage *image = new QImage(x1 - x0, height(), QImage::Format_RGB32);

    QPainter *paint = new QPainter(image);
    if (!render(*paint, 0, f0, f1)) {
        delete paint;
        delete image;
        return 0;
    } else {
        delete paint;
        return image;
    }
}

QSize
View::getImageSize()
{
    size_t f0 = getModelsStartFrame();
    size_t f1 = getModelsEndFrame();

    return getImageSize(f0, f1);
}
    
QSize
View::getImageSize(size_t f0, size_t f1)
{
    size_t x0 = f0 / getZoomLevel();
    size_t x1 = f1 / getZoomLevel();

    return QSize(x1 - x0, height());
}

void
View::toXml(QTextStream &stream,
            QString indent, QString extraAttributes) const
{
    stream << indent;

    stream << QString("<view "
                      "centre=\"%1\" "
                      "zoom=\"%2\" "
                      "followPan=\"%3\" "
                      "followZoom=\"%4\" "
                      "tracking=\"%5\" "
                      " %6>\n")
	.arg(m_centreFrame)
	.arg(m_zoomLevel)
	.arg(m_followPan)
	.arg(m_followZoom)
	.arg(m_followPlay == PlaybackScrollContinuous ? "scroll" :
	     m_followPlay == PlaybackScrollPage ? "page" : "ignore")
	.arg(extraAttributes);

    for (size_t i = 0; i < m_layers.size(); ++i) {
        bool visible = !m_layers[i]->isLayerDormant(this);
        m_layers[i]->toBriefXml(stream, indent + "  ",
                                QString("visible=\"%1\"")
                                .arg(visible ? "true" : "false"));
    }

    stream << indent + "</view>\n";
}

ViewPropertyContainer::ViewPropertyContainer(View *v) :
    m_v(v)
{
    connect(m_v, SIGNAL(propertyChanged(PropertyContainer::PropertyName)),
	    this, SIGNAL(propertyChanged(PropertyContainer::PropertyName)));
}