annotate layer/SpectrogramLayer.cpp @ 381:44670ce11a0c spectrogram-cache-rejig

* Some debug output and tweaks

/* -*- 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 and QMUL.
    
    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 "SpectrogramLayer.h"

#include "view/View.h"
#include "base/Profiler.h"
#include "base/AudioLevel.h"
#include "base/Window.h"
#include "base/Pitch.h"
#include "base/Preferences.h"
#include "base/RangeMapper.h"
#include "base/LogRange.h"
#include "base/CommandHistory.h"
#include "base/ColourMapper.h"
#include "ImageRegionFinder.h"

#include <QPainter>
#include <QImage>
#include <QPixmap>
#include <QRect>
#include <QTimer>
#include <QApplication>
#include <QMessageBox>
#include <QMouseEvent>
#include <QTextStream>

#include <iostream>

#include <cassert>
#include <cmath>

#define DEBUG_SPECTROGRAM_REPAINT 1

SpectrogramLayer::SpectrogramLayer(Configuration config) :
    m_model(0),
    m_channel(0),
    m_windowSize(1024),
    m_windowType(HanningWindow),
    m_windowHopLevel(2),
    m_zeroPadLevel(0),
    m_fftSize(1024),
    m_gain(1.0),
    m_initialGain(1.0),
    m_threshold(0.0),
    m_initialThreshold(0.0),
    m_colourRotation(0),
    m_initialRotation(0),
    m_minFrequency(10),
    m_maxFrequency(8000),
    m_initialMaxFrequency(8000),
    m_colourScale(dBColourScale),
    m_colourMap(0),
    m_frequencyScale(LinearFrequencyScale),
    m_binDisplay(AllBins),
    m_normalizeColumns(false),
    m_normalizeVisibleArea(false),
    m_lastEmittedZoomStep(-1),
    m_lastPaintBlockWidth(0),
    m_updateTimer(0),
    m_candidateFillStartFrame(0),
    m_exiting(false),
    m_sliceableModel(0)
{
    if (config == FullRangeDb) {
        m_initialMaxFrequency = 0;
        setMaxFrequency(0);
    } else if (config == MelodicRange) {
	setWindowSize(8192);
	setWindowHopLevel(4);
        m_initialMaxFrequency = 1500;
	setMaxFrequency(1500);
        setMinFrequency(40);
	setColourScale(LinearColourScale);
        setColourMap(ColourMapper::Sunset);
        setFrequencyScale(LogFrequencyScale);
//        setGain(20);
    } else if (config == MelodicPeaks) {
	setWindowSize(4096);
	setWindowHopLevel(5);
        m_initialMaxFrequency = 2000;
	setMaxFrequency(2000);
	setMinFrequency(40);
	setFrequencyScale(LogFrequencyScale);
	setColourScale(LinearColourScale);
	setBinDisplay(PeakFrequencies);
	setNormalizeColumns(true);
    }

    Preferences *prefs = Preferences::getInstance();
    connect(prefs, SIGNAL(propertyChanged(PropertyContainer::PropertyName)),
            this, SLOT(preferenceChanged(PropertyContainer::PropertyName)));
    setWindowType(prefs->getWindowType());

    initialisePalette();

    m_paintThread = new PaintThread(this);
    m_paintThread->start();
}

SpectrogramLayer::~SpectrogramLayer()
{
    if (m_paintThread) {
        m_paintThread->exiting();
        m_paintThread->wait();
        delete m_paintThread;
    }

    m_pixmapCacheMutex.lock();

    while (!m_pixmapCaches.empty()) {

        PixmapCache *cache = m_pixmapCaches.begin()->second;

        cache->mutex.lock();
        delete cache->pixmap;
        cache->pixmap = 0;
        cache->mutex.unlock();

        delete cache;
        m_pixmapCaches.erase(m_pixmapCaches.begin());
    }

    m_pixmapCacheMutex.unlock();

    delete m_updateTimer;
    m_updateTimer = 0;
    
    invalidateFFTModels();
}

void
SpectrogramLayer::setModel(const DenseTimeValueModel *model)
{
//    std::cerr << "SpectrogramLayer(" << this << "): setModel(" << model << ")" << std::endl;

    if (model == m_model) return;

    m_model = model;
    invalidateFFTModels();

    if (!m_model || !m_model->isOK()) return;

    connectSignals(m_model);

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

    emit modelReplaced();
}

Layer::PropertyList
SpectrogramLayer::getProperties() const
{
    PropertyList list;
    list.push_back("Colour");
    list.push_back("Colour Scale");
    list.push_back("Window Size");
    list.push_back("Window Increment");
    list.push_back("Normalize Columns");
    list.push_back("Normalize Visible Area");
    list.push_back("Bin Display");
    list.push_back("Threshold");
    list.push_back("Gain");
    list.push_back("Colour Rotation");
//    list.push_back("Min Frequency");
//    list.push_back("Max Frequency");
    list.push_back("Frequency Scale");
////    list.push_back("Zero Padding");
    return list;
}

QString
SpectrogramLayer::getPropertyIconName(const PropertyName &name) const
{
    if (name == "Normalize Columns") return "normalise-columns";
    if (name == "Normalize Visible Area") return "normalise";
    return "";
}

QString
SpectrogramLayer::getPropertyLabel(const PropertyName &name) const
{
    if (name == "Colour") return tr("Colour");
    if (name == "Colour Scale") return tr("Colour Scale");
    if (name == "Window Size") return tr("Window Size");
    if (name == "Window Increment") return tr("Window Overlap");
    if (name == "Normalize Columns") return tr("Normalize Columns");
    if (name == "Normalize Visible Area") return tr("Normalize Visible Area");
    if (name == "Bin Display") return tr("Bin Display");
    if (name == "Threshold") return tr("Threshold");
    if (name == "Gain") return tr("Gain");
    if (name == "Colour Rotation") return tr("Colour Rotation");
    if (name == "Min Frequency") return tr("Min Frequency");
    if (name == "Max Frequency") return tr("Max Frequency");
    if (name == "Frequency Scale") return tr("Frequency Scale");
    if (name == "Zero Padding") return tr("Smoothing");
    return "";
}

Layer::PropertyType
SpectrogramLayer::getPropertyType(const PropertyName &name) const
{
    if (name == "Gain") return RangeProperty;
    if (name == "Colour Rotation") return RangeProperty;
    if (name == "Normalize Columns") return ToggleProperty;
    if (name == "Normalize Visible Area") return ToggleProperty;
    if (name == "Threshold") return RangeProperty;
    if (name == "Zero Padding") return ToggleProperty;
    return ValueProperty;
}

QString
SpectrogramLayer::getPropertyGroupName(const PropertyName &name) const
{
    if (name == "Bin Display" ||
        name == "Frequency Scale") return tr("Bins");
    if (name == "Window Size" ||
	name == "Window Increment" ||
        name == "Zero Padding") return tr("Window");
    if (name == "Colour" ||
	name == "Threshold" ||
	name == "Colour Rotation") return tr("Colour");
    if (name == "Normalize Columns" ||
        name == "Normalize Visible Area" ||
        name == "Gain" ||
	name == "Colour Scale") return tr("Scale");
    return QString();
}

int
SpectrogramLayer::getPropertyRangeAndValue(const PropertyName &name,
					   int *min, int *max, int *deflt) const
{
    int val = 0;

    int garbage0, garbage1, garbage2;
    if (!min) min = &garbage0;
    if (!max) max = &garbage1;
    if (!deflt) deflt = &garbage2;

    if (name == "Gain") {

	*min = -50;
	*max = 50;

        *deflt = lrintf(log10(m_initialGain) * 20.0);;
	if (*deflt < *min) *deflt = *min;
	if (*deflt > *max) *deflt = *max;

	val = lrintf(log10(m_gain) * 20.0);
	if (val < *min) val = *min;
	if (val > *max) val = *max;

    } else if (name == "Threshold") {

	*min = -50;
	*max = 0;

        *deflt = lrintf(AudioLevel::multiplier_to_dB(m_initialThreshold));
	if (*deflt < *min) *deflt = *min;
	if (*deflt > *max) *deflt = *max;

	val = lrintf(AudioLevel::multiplier_to_dB(m_threshold));
	if (val < *min) val = *min;
	if (val > *max) val = *max;

    } else if (name == "Colour Rotation") {

	*min = 0;
	*max = 256;
        *deflt = m_initialRotation;

	val = m_colourRotation;

    } else if (name == "Colour Scale") {

	*min = 0;
	*max = 4;
        *deflt = int(dBColourScale);

	val = (int)m_colourScale;

    } else if (name == "Colour") {

	*min = 0;
	*max = ColourMapper::getColourMapCount() - 1;
        *deflt = 0;

	val = m_colourMap;

    } else if (name == "Window Size") {

	*min = 0;
	*max = 10;
        *deflt = 5;
	
	val = 0;
	int ws = m_windowSize;
	while (ws > 32) { ws >>= 1; val ++; }

    } else if (name == "Window Increment") {
	
	*min = 0;
	*max = 5;
        *deflt = 2;

        val = m_windowHopLevel;
    
    } else if (name == "Zero Padding") {
	
	*min = 0;
	*max = 1;
        *deflt = 0;
	
        val = m_zeroPadLevel > 0 ? 1 : 0;
    
    } else if (name == "Min Frequency") {

	*min = 0;
	*max = 9;
        *deflt = 1;

	switch (m_minFrequency) {
	case 0: default: val = 0; break;
	case 10: val = 1; break;
	case 20: val = 2; break;
	case 40: val = 3; break;
	case 100: val = 4; break;
	case 250: val = 5; break;
	case 500: val = 6; break;
	case 1000: val = 7; break;
	case 4000: val = 8; break;
	case 10000: val = 9; break;
	}
    
    } else if (name == "Max Frequency") {

	*min = 0;
	*max = 9;
        *deflt = 6;

	switch (m_maxFrequency) {
	case 500: val = 0; break;
	case 1000: val = 1; break;
	case 1500: val = 2; break;
	case 2000: val = 3; break;
	case 4000: val = 4; break;
	case 6000: val = 5; break;
	case 8000: val = 6; break;
	case 12000: val = 7; break;
	case 16000: val = 8; break;
	default: val = 9; break;
	}

    } else if (name == "Frequency Scale") {

	*min = 0;
	*max = 1;
        *deflt = int(LinearFrequencyScale);
	val = (int)m_frequencyScale;

    } else if (name == "Bin Display") {

	*min = 0;
	*max = 2;
        *deflt = int(AllBins);
	val = (int)m_binDisplay;

    } else if (name == "Normalize Columns") {
	
        *deflt = 0;
	val = (m_normalizeColumns ? 1 : 0);

    } else if (name == "Normalize Visible Area") {
	
        *deflt = 0;
	val = (m_normalizeVisibleArea ? 1 : 0);

    } else {
	val = Layer::getPropertyRangeAndValue(name, min, max, deflt);
    }

    return val;
}

QString
SpectrogramLayer::getPropertyValueLabel(const PropertyName &name,
					int value) const
{
    if (name == "Colour") {
        return ColourMapper::getColourMapName(value);
    }
    if (name == "Colour Scale") {
	switch (value) {
	default:
	case 0: return tr("Linear");
	case 1: return tr("Meter");
	case 2: return tr("dBV^2");
	case 3: return tr("dBV");
	case 4: return tr("Phase");
	}
    }
    if (name == "Window Size") {
	return QString("%1").arg(32 << value);
    }
    if (name == "Window Increment") {
	switch (value) {
	default:
	case 0: return tr("None");
	case 1: return tr("25 %");
	case 2: return tr("50 %");
	case 3: return tr("75 %");
	case 4: return tr("87.5 %");
	case 5: return tr("93.75 %");
	}
    }
    if (name == "Zero Padding") {
        if (value == 0) return tr("None");
        return QString("%1x").arg(value + 1);
    }
    if (name == "Min Frequency") {
	switch (value) {
	default:
	case 0: return tr("No min");
	case 1: return tr("10 Hz");
	case 2: return tr("20 Hz");
	case 3: return tr("40 Hz");
	case 4: return tr("100 Hz");
	case 5: return tr("250 Hz");
	case 6: return tr("500 Hz");
	case 7: return tr("1 KHz");
	case 8: return tr("4 KHz");
	case 9: return tr("10 KHz");
	}
    }
    if (name == "Max Frequency") {
	switch (value) {
	default:
	case 0: return tr("500 Hz");
	case 1: return tr("1 KHz");
	case 2: return tr("1.5 KHz");
	case 3: return tr("2 KHz");
	case 4: return tr("4 KHz");
	case 5: return tr("6 KHz");
	case 6: return tr("8 KHz");
	case 7: return tr("12 KHz");
	case 8: return tr("16 KHz");
	case 9: return tr("No max");
	}
    }
    if (name == "Frequency Scale") {
	switch (value) {
	default:
	case 0: return tr("Linear");
	case 1: return tr("Log");
	}
    }
    if (name == "Bin Display") {
	switch (value) {
	default:
	case 0: return tr("All Bins");
	case 1: return tr("Peak Bins");
	case 2: return tr("Frequencies");
	}
    }
    return tr("<unknown>");
}

RangeMapper *
SpectrogramLayer::getNewPropertyRangeMapper(const PropertyName &name) const
{
    if (name == "Gain") {
        return new LinearRangeMapper(-50, 50, -25, 25, tr("dB"));
    }
    if (name == "Threshold") {
        return new LinearRangeMapper(-50, 0, -50, 0, tr("dB"));
    }
    return 0;
}

void
SpectrogramLayer::setProperty(const PropertyName &name, int value)
{
    if (name == "Gain") {
	setGain(pow(10, float(value)/20.0));
    } else if (name == "Threshold") {
	if (value == -50) setThreshold(0.0);
	else setThreshold(AudioLevel::dB_to_multiplier(value));
    } else if (name == "Colour Rotation") {
	setColourRotation(value);
    } else if (name == "Colour") {
        setColourMap(value);
    } else if (name == "Window Size") {
	setWindowSize(32 << value);
    } else if (name == "Window Increment") {
        setWindowHopLevel(value);
    } else if (name == "Zero Padding") {
        setZeroPadLevel(value > 0.1 ? 3 : 0);
    } else if (name == "Min Frequency") {
	switch (value) {
	default:
	case 0: setMinFrequency(0); break;
	case 1: setMinFrequency(10); break;
	case 2: setMinFrequency(20); break;
	case 3: setMinFrequency(40); break;
	case 4: setMinFrequency(100); break;
	case 5: setMinFrequency(250); break;
	case 6: setMinFrequency(500); break;
	case 7: setMinFrequency(1000); break;
	case 8: setMinFrequency(4000); break;
	case 9: setMinFrequency(10000); break;
	}
        int vs = getCurrentVerticalZoomStep();
        if (vs != m_lastEmittedZoomStep) {
            emit verticalZoomChanged();
            m_lastEmittedZoomStep = vs;
        }
    } else if (name == "Max Frequency") {
	switch (value) {
	case 0: setMaxFrequency(500); break;
	case 1: setMaxFrequency(1000); break;
	case 2: setMaxFrequency(1500); break;
	case 3: setMaxFrequency(2000); break;
	case 4: setMaxFrequency(4000); break;
	case 5: setMaxFrequency(6000); break;
	case 6: setMaxFrequency(8000); break;
	case 7: setMaxFrequency(12000); break;
	case 8: setMaxFrequency(16000); break;
	default:
	case 9: setMaxFrequency(0); break;
	}
        int vs = getCurrentVerticalZoomStep();
        if (vs != m_lastEmittedZoomStep) {
            emit verticalZoomChanged();
            m_lastEmittedZoomStep = vs;
        }
    } else if (name == "Colour Scale") {
	switch (value) {
	default:
	case 0: setColourScale(LinearColourScale); break;
	case 1: setColourScale(MeterColourScale); break;
	case 2: setColourScale(dBSquaredColourScale); break;
	case 3: setColourScale(dBColourScale); break;
	case 4: setColourScale(PhaseColourScale); break;
	}
    } else if (name == "Frequency Scale") {
	switch (value) {
	default:
	case 0: setFrequencyScale(LinearFrequencyScale); break;
	case 1: setFrequencyScale(LogFrequencyScale); break;
	}
    } else if (name == "Bin Display") {
	switch (value) {
	default:
	case 0: setBinDisplay(AllBins); break;
	case 1: setBinDisplay(PeakBins); break;
	case 2: setBinDisplay(PeakFrequencies); break;
	}
    } else if (name == "Normalize Columns") {
	setNormalizeColumns(value ? true : false);
    } else if (name == "Normalize Visible Area") {
	setNormalizeVisibleArea(value ? true : false);
    }
}

void
SpectrogramLayer::invalidatePixmapCaches()
{
    QMutexLocker locker(&m_pixmapCacheMutex);

    for (ViewPixmapCache::iterator i = m_pixmapCaches.begin();
         i != m_pixmapCaches.end(); ++i) {

        QMutexLocker locker(&i->second->mutex);
        i->second->validArea = QRect();
    }
}

void
SpectrogramLayer::invalidatePixmapCaches(size_t startFrame, size_t endFrame)
{
    QMutexLocker locker(&m_pixmapCacheMutex);

    for (ViewPixmapCache::iterator i = m_pixmapCaches.begin();
         i != m_pixmapCaches.end(); ++i) {

        QMutexLocker locker(&i->second->mutex);

        //!!! when are views removed from the map? on setLayerDormant?
        const View *v = i->first;

        if (startFrame < v->getEndFrame() && int(endFrame) >= v->getStartFrame()) {
            i->second->validArea = QRect();
        }
    }
}

void
SpectrogramLayer::preferenceChanged(PropertyContainer::PropertyName name)
{
    std::cerr << "SpectrogramLayer::preferenceChanged(" << name.toStdString() << ")" << std::endl;

    if (name == "Window Type") {
        setWindowType(Preferences::getInstance()->getWindowType());
        return;
    }
    if (name == "Spectrogram Smoothing") {
        invalidatePixmapCaches();
        invalidateMagnitudes();
        emit layerParametersChanged();
    }
    if (name == "Tuning Frequency") {
        emit layerParametersChanged();
    }
}

void
SpectrogramLayer::setChannel(int ch)
{
    if (m_channel == ch) return;

    invalidatePixmapCaches();
    m_channel = ch;
    invalidateFFTModels();

    emit layerParametersChanged();
}

int
SpectrogramLayer::getChannel() const
{
    return m_channel;
}

void
SpectrogramLayer::setWindowSize(size_t ws)
{
    if (m_windowSize == ws) return;

    invalidatePixmapCaches();
    
    m_windowSize = ws;
    m_fftSize = ws * (m_zeroPadLevel + 1);
    
    invalidateFFTModels();

    emit layerParametersChanged();
}

size_t
SpectrogramLayer::getWindowSize() const
{
    return m_windowSize;
}

void
SpectrogramLayer::setWindowHopLevel(size_t v)
{
    if (m_windowHopLevel == v) return;

    invalidatePixmapCaches();
    
    m_windowHopLevel = v;
    
    invalidateFFTModels();

    emit layerParametersChanged();

//    fillCache();
}

size_t
SpectrogramLayer::getWindowHopLevel() const
{
    return m_windowHopLevel;
}

void
SpectrogramLayer::setZeroPadLevel(size_t v)
{
    if (m_zeroPadLevel == v) return;

    invalidatePixmapCaches();
    
    m_zeroPadLevel = v;
    m_fftSize = m_windowSize * (v + 1);

    invalidateFFTModels();

    emit layerParametersChanged();
}

size_t
SpectrogramLayer::getZeroPadLevel() const
{
    return m_zeroPadLevel;
}

void
SpectrogramLayer::setWindowType(WindowType w)
{
    if (m_windowType == w) return;

    invalidatePixmapCaches();
    
    m_windowType = w;

    invalidateFFTModels();

    emit layerParametersChanged();
}

WindowType
SpectrogramLayer::getWindowType() const
{
    return m_windowType;
}

void
SpectrogramLayer::setGain(float gain)
{
//    std::cerr << "SpectrogramLayer::setGain(" << gain << ") (my gain is now "
//	      << m_gain << ")" << std::endl;

    if (m_gain == gain) return;

    invalidatePixmapCaches();
    
    m_gain = gain;
    
    emit layerParametersChanged();
}

float
SpectrogramLayer::getGain() const
{
    return m_gain;
}

void
SpectrogramLayer::setThreshold(float threshold)
{
    if (m_threshold == threshold) return;

    invalidatePixmapCaches();
    
    m_threshold = threshold;

    emit layerParametersChanged();
}

float
SpectrogramLayer::getThreshold() const
{
    return m_threshold;
}

void
SpectrogramLayer::setMinFrequency(size_t mf)
{
    if (m_minFrequency == mf) return;

//    std::cerr << "SpectrogramLayer::setMinFrequency: " << mf << std::endl;

    invalidatePixmapCaches();
    invalidateMagnitudes();
    
    m_minFrequency = mf;

    emit layerParametersChanged();
}

size_t
SpectrogramLayer::getMinFrequency() const
{
    return m_minFrequency;
}

void
SpectrogramLayer::setMaxFrequency(size_t mf)
{
    if (m_maxFrequency == mf) return;

//    std::cerr << "SpectrogramLayer::setMaxFrequency: " << mf << std::endl;

    invalidatePixmapCaches();
    invalidateMagnitudes();
    
    m_maxFrequency = mf;
    
    emit layerParametersChanged();
}

size_t
SpectrogramLayer::getMaxFrequency() const
{
    return m_maxFrequency;
}

void
SpectrogramLayer::setColourRotation(int r)
{
    invalidatePixmapCaches();

    if (r < 0) r = 0;
    if (r > 256) r = 256;
    int distance = r - m_colourRotation;

    if (distance != 0) {
	rotatePalette(-distance);
	m_colourRotation = r;
    }
    
    emit layerParametersChanged();
}

void
SpectrogramLayer::setColourScale(ColourScale colourScale)
{
    if (m_colourScale == colourScale) return;

    invalidatePixmapCaches();
    
    m_colourScale = colourScale;
    
    emit layerParametersChanged();
}

SpectrogramLayer::ColourScale
SpectrogramLayer::getColourScale() const
{
    return m_colourScale;
}

void
SpectrogramLayer::setColourMap(int map)
{
    if (m_colourMap == map) return;

    invalidatePixmapCaches();
    
    m_colourMap = map;
    initialisePalette();

    emit layerParametersChanged();
}

int
SpectrogramLayer::getColourMap() const
{
    return m_colourMap;
}

void
SpectrogramLayer::setFrequencyScale(FrequencyScale frequencyScale)
{
    if (m_frequencyScale == frequencyScale) return;

    invalidatePixmapCaches();
    m_frequencyScale = frequencyScale;

    emit layerParametersChanged();
}

SpectrogramLayer::FrequencyScale
SpectrogramLayer::getFrequencyScale() const
{
    return m_frequencyScale;
}

void
SpectrogramLayer::setBinDisplay(BinDisplay binDisplay)
{
    if (m_binDisplay == binDisplay) return;

    invalidatePixmapCaches();
    m_binDisplay = binDisplay;

    emit layerParametersChanged();
}

SpectrogramLayer::BinDisplay
SpectrogramLayer::getBinDisplay() const
{
    return m_binDisplay;
}

void
SpectrogramLayer::setNormalizeColumns(bool n)
{
    if (m_normalizeColumns == n) return;

    invalidatePixmapCaches();
    invalidateMagnitudes();
    m_normalizeColumns = n;

    emit layerParametersChanged();
}

bool
SpectrogramLayer::getNormalizeColumns() const
{
    return m_normalizeColumns;
}

void
SpectrogramLayer::setNormalizeVisibleArea(bool n)
{
    std::cerr << "SpectrogramLayer::setNormalizeVisibleArea(" << n
              << ") (from " << m_normalizeVisibleArea << ")" << std::endl;

    if (m_normalizeVisibleArea == n) return;

    invalidatePixmapCaches();
    invalidateMagnitudes();
    m_normalizeVisibleArea = n;

    emit layerParametersChanged();
}

bool
SpectrogramLayer::getNormalizeVisibleArea() const
{
    return m_normalizeVisibleArea;
}

void
SpectrogramLayer::setLayerDormant(const View *v, bool dormant)
{
    if (dormant) {

        if (isLayerDormant(v)) {
            return;
        }

        Layer::setLayerDormant(v, true);

	invalidatePixmapCaches();

        m_pixmapCacheMutex.lock();

        m_pixmapCaches[v]->mutex.lock();
        delete m_pixmapCaches[v]->pixmap;
        m_pixmapCaches[v]->pixmap = 0;
        m_pixmapCaches[v]->mutex.unlock();

        delete m_pixmapCaches[v];
        m_pixmapCaches.erase(v);

        m_pixmapCacheMutex.unlock();

        if (m_fftModels.find(v) != m_fftModels.end()) {

            if (m_sliceableModel == m_fftModels[v].first) {
                bool replaced = false;
                for (ViewFFTMap::iterator i = m_fftModels.begin();
                     i != m_fftModels.end(); ++i) {
                    if (i->second.first != m_sliceableModel) {
                        emit sliceableModelReplaced(m_sliceableModel, i->second.first);
                        replaced = true;
                        break;
                    }
                }
                if (!replaced) emit sliceableModelReplaced(m_sliceableModel, 0);
            }

            delete m_fftModels[v].first;
            m_fftModels.erase(v);
        }
	
    } else {

        Layer::setLayerDormant(v, false);
    }
}

void
SpectrogramLayer::cacheInvalid()
{
    invalidatePixmapCaches();
    invalidateMagnitudes();
}

void
SpectrogramLayer::cacheInvalid(size_t, size_t)
{
    // for now (or forever?)
    cacheInvalid();
}

void
SpectrogramLayer::fillTimerTimedOut()
{
    if (!m_model) return;

    bool allDone = true;

#ifdef DEBUG_SPECTROGRAM_REPAINT
    std::cerr << "SpectrogramLayer::fillTimerTimedOut: have " << m_fftModels.size() << " FFT models associated with views" << std::endl;
#endif

    for (ViewFFTMap::iterator i = m_fftModels.begin();
         i != m_fftModels.end(); ++i) {

        const FFTModel *model = i->second.first;
        size_t lastFill = i->second.second;

        if (model) {

            size_t fill = model->getFillExtent();

#ifdef DEBUG_SPECTROGRAM_REPAINT
            std::cerr << "SpectrogramLayer::fillTimerTimedOut: extent for " << model << ": " << fill << ", last " << lastFill << ", total " << m_model->getEndFrame() << std::endl;
#endif

            if (fill >= lastFill) {
                if (fill >= m_model->getEndFrame() && lastFill > 0) {
#ifdef DEBUG_SPECTROGRAM_REPAINT
                    std::cerr << "complete!" << std::endl;
#endif
                    invalidatePixmapCaches();
                    i->second.second = -1;
                    emit modelChanged();

                } else if (fill > lastFill) {
#ifdef DEBUG_SPECTROGRAM_REPAINT
                    std::cerr << "SpectrogramLayer: emitting modelChanged("
                              << lastFill << "," << fill << ")" << std::endl;
#endif
                    invalidatePixmapCaches(lastFill, fill);
                    i->second.second = fill;
                    emit modelChanged(lastFill, fill);
                }
            } else {
#ifdef DEBUG_SPECTROGRAM_REPAINT
                std::cerr << "SpectrogramLayer: going backwards, emitting modelChanged("
                          << m_model->getStartFrame() << "," << m_model->getEndFrame() << ")" << std::endl;
#endif
                invalidatePixmapCaches();
                i->second.second = fill;
                emit modelChanged(m_model->getStartFrame(), m_model->getEndFrame());
            }

            if (i->second.second >= 0) {
                allDone = false;
            }
        }
    }

    if (allDone) {
#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "SpectrogramLayer: all complete!" << std::endl;
#endif
        delete m_updateTimer;
        m_updateTimer = 0;
    }
}

bool
SpectrogramLayer::hasLightBackground() const 
{
    return ColourMapper(m_colourMap, 1.f, 255.f).hasLightBackground();
}

void
SpectrogramLayer::initialisePalette()
{
    int formerRotation = m_colourRotation;

    if (m_colourMap == (int)ColourMapper::BlackOnWhite) {
	m_palette.setColour(NO_VALUE, Qt::white);
    } else {
	m_palette.setColour(NO_VALUE, Qt::black);
    }

    ColourMapper mapper(m_colourMap, 1.f, 255.f);
    
    for (int pixel = 1; pixel < 256; ++pixel) {
        m_palette.setColour(pixel, mapper.map(pixel));
    }

    m_crosshairColour = mapper.getContrastingColour();

    m_colourRotation = 0;
    rotatePalette(m_colourRotation - formerRotation);
    m_colourRotation = formerRotation;
}

void
SpectrogramLayer::rotatePalette(int distance)
{
    QColor newPixels[256];

    newPixels[NO_VALUE] = m_palette.getColour(NO_VALUE);

    for (int pixel = 1; pixel < 256; ++pixel) {
	int target = pixel + distance;
	while (target < 1) target += 255;
	while (target > 255) target -= 255;
	newPixels[target] = m_palette.getColour(pixel);
    }

    for (int pixel = 0; pixel < 256; ++pixel) {
	m_palette.setColour(pixel, newPixels[pixel]);
    }
}

unsigned char
SpectrogramLayer::getDisplayValue(View *v, float input) const
{
    int value;

    float min = 0.f;
    float max = 1.f;

    if (m_normalizeVisibleArea) {
        min = m_viewMags[v].getMin();
        max = m_viewMags[v].getMax();
    } else if (!m_normalizeColumns) {
        if (m_colourScale == LinearColourScale //||
//            m_colourScale == MeterColourScale) {
            ) {
            max = 0.1f;
        }
    }

    float thresh = -80.f;

    if (max == 0.f) max = 1.f;
    if (max == min) min = max - 0.0001f;

    switch (m_colourScale) {
	
    default:
    case LinearColourScale:
        value = int(((input - min) / (max - min)) * 255.f) + 1;
	break;
	
    case MeterColourScale:
        value = AudioLevel::multiplier_to_preview
            ((input - min) / (max - min), 254) + 1;
	break;

    case dBSquaredColourScale:
        input = ((input - min) * (input - min)) / ((max - min) * (max - min));
        if (input > 0.f) {
            input = 10.f * log10f(input);
        } else {
            input = thresh;
        }
        if (min > 0.f) {
            thresh = 10.f * log10f(min * min);
            if (thresh < -80.f) thresh = -80.f;
        }
	input = (input - thresh) / (-thresh);
	if (input < 0.f) input = 0.f;
	if (input > 1.f) input = 1.f;
	value = int(input * 255.f) + 1;
	break;
	
    case dBColourScale:
        //!!! experiment with normalizing the visible area this way.
        //In any case, we need to have some indication of what the dB
        //scale is relative to.
        input = (input - min) / (max - min);
        if (input > 0.f) {
            input = 10.f * log10f(input);
        } else {
            input = thresh;
        }
        if (min > 0.f) {
            thresh = 10.f * log10f(min);
            if (thresh < -80.f) thresh = -80.f;
        }
	input = (input - thresh) / (-thresh);
	if (input < 0.f) input = 0.f;
	if (input > 1.f) input = 1.f;
	value = int(input * 255.f) + 1;
	break;
	
    case PhaseColourScale:
	value = int((input * 127.0 / M_PI) + 128);
	break;
    }

    if (value > UCHAR_MAX) value = UCHAR_MAX;
    if (value < 0) value = 0;
    return value;
}

float
SpectrogramLayer::getInputForDisplayValue(unsigned char uc) const
{
    //!!! unused

    int value = uc;
    float input;

    //!!! incorrect for normalizing visible area (and also out of date)
    
    switch (m_colourScale) {
	
    default:
    case LinearColourScale:
	input = float(value - 1) / 255.0 / (m_normalizeColumns ? 1 : 50);
	break;
    
    case MeterColourScale:
	input = AudioLevel::preview_to_multiplier(value - 1, 255)
	    / (m_normalizeColumns ? 1.0 : 50.0);
	break;

    case dBSquaredColourScale:
	input = float(value - 1) / 255.0;
	input = (input * 80.0) - 80.0;
	input = powf(10.0, input) / 20.0;
	value = int(input);
	break;

    case dBColourScale:
	input = float(value - 1) / 255.0;
	input = (input * 80.0) - 80.0;
	input = powf(10.0, input) / 20.0;
	value = int(input);
	break;

    case PhaseColourScale:
	input = float(value - 128) * M_PI / 127.0;
	break;
    }

    return input;
}

float
SpectrogramLayer::getEffectiveMinFrequency() const
{
    int sr = m_model->getSampleRate();
    float minf = float(sr) / m_fftSize;

    if (m_minFrequency > 0.0) {
	size_t minbin = size_t((double(m_minFrequency) * m_fftSize) / sr + 0.01);
	if (minbin < 1) minbin = 1;
	minf = minbin * sr / m_fftSize;
    }

    return minf;
}

float
SpectrogramLayer::getEffectiveMaxFrequency() const
{
    int sr = m_model->getSampleRate();
    float maxf = float(sr) / 2;

    if (m_maxFrequency > 0.0) {
	size_t maxbin = size_t((double(m_maxFrequency) * m_fftSize) / sr + 0.1);
	if (maxbin > m_fftSize / 2) maxbin = m_fftSize / 2;
	maxf = maxbin * sr / m_fftSize;
    }

    return maxf;
}

bool
SpectrogramLayer::getYBinRange(View *v, int y, float &q0, float &q1) const
{
    int h = v->height();
    if (y < 0 || y >= h) return false;

    int sr = m_model->getSampleRate();
    float minf = getEffectiveMinFrequency();
    float maxf = getEffectiveMaxFrequency();

    bool logarithmic = (m_frequencyScale == LogFrequencyScale);

    //!!! wrong for smoothing -- wrong fft size for fft model

    q0 = v->getFrequencyForY(y, minf, maxf, logarithmic);
    q1 = v->getFrequencyForY(y - 1, minf, maxf, logarithmic);

    // Now map these on to actual bins

    int b0 = int((q0 * m_fftSize) / sr);
    int b1 = int((q1 * m_fftSize) / sr);
    
    //!!! this is supposed to return fractions-of-bins, as it were, hence the floats
    q0 = b0;
    q1 = b1;
    
//    q0 = (b0 * sr) / m_fftSize;
//    q1 = (b1 * sr) / m_fftSize;

    return true;
}
    
bool
SpectrogramLayer::getXBinRange(View *v, int x, float &s0, float &s1) const
{
    size_t modelStart = m_model->getStartFrame();
    size_t modelEnd = m_model->getEndFrame();

    // Each pixel column covers an exact range of sample frames:
    int f0 = v->getFrameForX(x) - modelStart;
    int f1 = v->getFrameForX(x + 1) - modelStart - 1;

    if (f1 < int(modelStart) || f0 > int(modelEnd)) {
	return false;
    }
      
    // And that range may be drawn from a possibly non-integral
    // range of spectrogram windows:

    size_t windowIncrement = getWindowIncrement();
    s0 = float(f0) / windowIncrement;
    s1 = float(f1) / windowIncrement;

    return true;
}
 
bool
SpectrogramLayer::getXBinSourceRange(View *v, int x, RealTime &min, RealTime &max) const
{
    float s0 = 0, s1 = 0;
    if (!getXBinRange(v, x, s0, s1)) return false;
    
    int s0i = int(s0 + 0.001);
    int s1i = int(s1);

    int windowIncrement = getWindowIncrement();
    int w0 = s0i * windowIncrement - (m_windowSize - windowIncrement)/2;
    int w1 = s1i * windowIncrement + windowIncrement +
	(m_windowSize - windowIncrement)/2 - 1;
    
    min = RealTime::frame2RealTime(w0, m_model->getSampleRate());
    max = RealTime::frame2RealTime(w1, m_model->getSampleRate());
    return true;
}

bool
SpectrogramLayer::getYBinSourceRange(View *v, int y, float &freqMin, float &freqMax)
const
{
    float q0 = 0, q1 = 0;
    if (!getYBinRange(v, y, q0, q1)) return false;

    int q0i = int(q0 + 0.001);
    int q1i = int(q1);

    int sr = m_model->getSampleRate();

    for (int q = q0i; q <= q1i; ++q) {
	if (q == q0i) freqMin = (sr * q) / m_fftSize;
	if (q == q1i) freqMax = (sr * (q+1)) / m_fftSize;
    }
    return true;
}

bool
SpectrogramLayer::getAdjustedYBinSourceRange(View *v, int x, int y,
					     float &freqMin, float &freqMax,
					     float &adjFreqMin, float &adjFreqMax)
const
{
    if (!m_model || !m_model->isOK() || !m_model->isReady()) {
	return false;
    }

    FFTModel *fft = getFFTModel(v);
    if (!fft) return false;

    float s0 = 0, s1 = 0;
    if (!getXBinRange(v, x, s0, s1)) return false;

    float q0 = 0, q1 = 0;
    if (!getYBinRange(v, y, q0, q1)) return false;

    int s0i = int(s0 + 0.001);
    int s1i = int(s1);

    int q0i = int(q0 + 0.001);
    int q1i = int(q1);

    int sr = m_model->getSampleRate();

    size_t windowSize = m_windowSize;
    size_t windowIncrement = getWindowIncrement();

    bool haveAdj = false;

    bool peaksOnly = (m_binDisplay == PeakBins ||
		      m_binDisplay == PeakFrequencies);

    for (int q = q0i; q <= q1i; ++q) {

	for (int s = s0i; s <= s1i; ++s) {

            if (!fft->isColumnAvailable(s)) continue;

	    float binfreq = (sr * q) / m_windowSize;
	    if (q == q0i) freqMin = binfreq;
	    if (q == q1i) freqMax = binfreq;

	    if (peaksOnly && !fft->isLocalPeak(s, q)) continue;

	    if (!fft->isOverThreshold(s, q, m_threshold * (m_fftSize/2))) continue;

	    float freq = binfreq;
	    bool steady = false;
	    
	    if (s < int(fft->getWidth()) - 1) {

                fft->estimateStableFrequency(s, q, freq);
	    
		if (!haveAdj || freq < adjFreqMin) adjFreqMin = freq;
		if (!haveAdj || freq > adjFreqMax) adjFreqMax = freq;

		haveAdj = true;
	    }
	}
    }

    if (!haveAdj) {
	adjFreqMin = adjFreqMax = 0.0;
    }

    return haveAdj;
}
    
bool
SpectrogramLayer::getXYBinSourceRange(View *v, int x, int y,
				      float &min, float &max,
				      float &phaseMin, float &phaseMax) const
{
    if (!m_model || !m_model->isOK() || !m_model->isReady()) {
	return false;
    }

    float q0 = 0, q1 = 0;
    if (!getYBinRange(v, y, q0, q1)) return false;

    float s0 = 0, s1 = 0;
    if (!getXBinRange(v, x, s0, s1)) return false;
    
    int q0i = int(q0 + 0.001);
    int q1i = int(q1);

    int s0i = int(s0 + 0.001);
    int s1i = int(s1);

    bool rv = false;

    size_t zp = getZeroPadLevel(v);
    q0i *= zp + 1;
    q1i *= zp + 1;

    FFTModel *fft = getFFTModel(v);

    if (fft) {

        int cw = fft->getWidth();
        int ch = fft->getHeight();

        min = 0.0;
        max = 0.0;
        phaseMin = 0.0;
        phaseMax = 0.0;
        bool have = false;

        for (int q = q0i; q <= q1i; ++q) {
            for (int s = s0i; s <= s1i; ++s) {
                if (s >= 0 && q >= 0 && s < cw && q < ch) {

                    if (!fft->isColumnAvailable(s)) continue;
                    
                    float value;

                    value = fft->getPhaseAt(s, q);
                    if (!have || value < phaseMin) { phaseMin = value; }
                    if (!have || value > phaseMax) { phaseMax = value; }

                    value = fft->getMagnitudeAt(s, q) / (m_fftSize/2);
                    if (!have || value < min) { min = value; }
                    if (!have || value > max) { max = value; }
                    
                    have = true;
                }	
            }
        }
        
        if (have) {
            rv = true;
        }
    }

    return rv;
}
   
size_t
SpectrogramLayer::getZeroPadLevel(const View *v) const
{
    //!!! tidy all this stuff

    if (m_binDisplay != AllBins) return 0;

    Preferences::SpectrogramSmoothing smoothing = 
        Preferences::getInstance()->getSpectrogramSmoothing();
    
    if (smoothing == Preferences::NoSpectrogramSmoothing ||
        smoothing == Preferences::SpectrogramInterpolated) return 0;

    if (m_frequencyScale == LogFrequencyScale) return 3;

    int sr = m_model->getSampleRate();
    
    size_t maxbin = m_fftSize / 2;
    if (m_maxFrequency > 0) {
	maxbin = int((double(m_maxFrequency) * m_fftSize) / sr + 0.1);
	if (maxbin > m_fftSize / 2) maxbin = m_fftSize / 2;
    }

    size_t minbin = 1;
    if (m_minFrequency > 0) {
	minbin = int((double(m_minFrequency) * m_fftSize) / sr + 0.1);
	if (minbin < 1) minbin = 1;
	if (minbin >= maxbin) minbin = maxbin - 1;
    }

    float perPixel =
        float(v->height()) /
        float((maxbin - minbin) / (m_zeroPadLevel + 1));

    if (perPixel > 2.8) {
        return 3; // 4x oversampling
    } else if (perPixel > 1.5) {
        return 1; // 2x
    } else {
        return 0; // 1x
    }
}

size_t
SpectrogramLayer::getFFTSize(const View *v) const
{
    return m_fftSize * (getZeroPadLevel(v) + 1);
}
	
FFTModel *
SpectrogramLayer::getFFTModel(const View *v) const
{
    //!!! need lock

    if (!m_model) return 0;

    size_t fftSize = getFFTSize(v);

    if (m_fftModels.find(v) != m_fftModels.end()) {
        if (m_fftModels[v].first == 0) {
#ifdef DEBUG_SPECTROGRAM_REPAINT
            std::cerr << "SpectrogramLayer::getFFTModel(" << v << "): Found null model" << std::endl;
#endif
            return 0;
        }
        if (m_fftModels[v].first->getHeight() != fftSize / 2 + 1) {
#ifdef DEBUG_SPECTROGRAM_REPAINT
            std::cerr << "SpectrogramLayer::getFFTModel(" << v << "): Found a model with the wrong height (" << m_fftModels[v].first->getHeight() << ", wanted " << (fftSize / 2 + 1) << ")" << std::endl;
#endif
            delete m_fftModels[v].first;
            m_fftModels.erase(v);
        } else {
#ifdef DEBUG_SPECTROGRAM_REPAINT
            std::cerr << "SpectrogramLayer::getFFTModel(" << v << "): Found a good model of height " << m_fftModels[v].first->getHeight() << std::endl;
#endif
            return m_fftModels[v].first;
        }
    }

    if (m_fftModels.find(v) == m_fftModels.end()) {

        FFTModel *model = new FFTModel(m_model,
                                       m_channel,
                                       m_windowType,
                                       m_windowSize,
                                       getWindowIncrement(),
                                       fftSize,
                                       true,
                                       StorageAdviser::SpeedCritical,
                                       m_candidateFillStartFrame);

        if (!model->isOK()) {
            QMessageBox::critical
                (0, tr("FFT cache failed"),
                 tr("Failed to create the FFT model for this spectrogram.\n"
                    "There may be insufficient memory or disc space to continue."));
            delete model;
            m_fftModels[v] = FFTFillPair(0, 0);
            return 0;
        }

        if (!m_sliceableModel) {
#ifdef DEBUG_SPECTROGRAM
            std::cerr << "SpectrogramLayer: emitting sliceableModelReplaced(0, " << model << ")" << std::endl;
#endif
            ((SpectrogramLayer *)this)->sliceableModelReplaced(0, model);
            m_sliceableModel = model;
        }

        m_fftModels[v] = FFTFillPair(model, 0);

        model->resume();
        
        delete m_updateTimer;
        m_updateTimer = new QTimer((SpectrogramLayer *)this);
        connect(m_updateTimer, SIGNAL(timeout()),
                this, SLOT(fillTimerTimedOut()));
        m_updateTimer->start(200);
    }

    return m_fftModels[v].first;
}

const Model *
SpectrogramLayer::getSliceableModel() const
{
    if (m_sliceableModel) return m_sliceableModel;
    if (m_fftModels.empty()) return 0;
    m_sliceableModel = m_fftModels.begin()->second.first;
    return m_sliceableModel;
}

void
SpectrogramLayer::invalidateFFTModels()
{
    for (ViewFFTMap::iterator i = m_fftModels.begin();
         i != m_fftModels.end(); ++i) {
        delete i->second.first;
    }
    
    m_fftModels.clear();

    if (m_sliceableModel) {
        std::cerr << "SpectrogramLayer: emitting sliceableModelReplaced(" << m_sliceableModel << ", 0)" << std::endl;
        emit sliceableModelReplaced(m_sliceableModel, 0);
        m_sliceableModel = 0;
    }
}

void
SpectrogramLayer::invalidateMagnitudes()
{
    m_viewMags.clear();
    for (std::vector<MagnitudeRange>::iterator i = m_columnMags.begin();
         i != m_columnMags.end(); ++i) {
        *i = MagnitudeRange();
    }
}

bool
SpectrogramLayer::updateViewMagnitudes(View *v) const
{
    MagnitudeRange mag;

    int x0 = 0, x1 = v->width();
    float s00 = 0, s01 = 0, s10 = 0, s11 = 0;
    
    if (!getXBinRange(v, x0, s00, s01)) {
        s00 = s01 = m_model->getStartFrame() / getWindowIncrement();
    }

    if (!getXBinRange(v, x1, s10, s11)) {
        s10 = s11 = m_model->getEndFrame() / getWindowIncrement();
    }

    int s0 = int(std::min(s00, s10) + 0.0001);
    int s1 = int(std::max(s01, s11) + 0.0001);

//    std::cerr << "SpectrogramLayer::updateViewMagnitudes: x0 = " << x0 << ", x1 = " << x1 << ", s00 = " << s00 << ", s11 = " << s11 << " s0 = " << s0 << ", s1 = " << s1 << std::endl;

    if (int(m_columnMags.size()) <= s1) {
        m_columnMags.resize(s1 + 1);
    }

    for (int s = s0; s <= s1; ++s) {
        if (m_columnMags[s].isSet()) {
            mag.sample(m_columnMags[s]);
        }
    }

#ifdef DEBUG_SPECTROGRAM_REPAINT
    std::cerr << "SpectrogramLayer::updateViewMagnitudes returning from cols "
              << s0 << " -> " << s1 << " inclusive" << std::endl;
#endif

    if (!mag.isSet()) return false;
    if (mag == m_viewMags[v]) return false;
    m_viewMags[v] = mag;
    return true;
}



// Plan:
//
// - the QImage cache is managed by the GUI thread (which creates,
// sizes and destroys it)
//
// - but the cache is drawn on by another thread (paint thread)
//
// - the GUI thread paint method should always just draw straight from
// cache without any lock, but it needs to check whether the cache is
// complete and schedule another update if it isn't
//
// - we need a mutex between cache construction/destruction activity
// and the paint thread (I wonder whether we need a general mutex
// between GUI thread changes to various parameters and paint thread
// access to those parameters?)
//!!! -> e.g. how is the access to FFTModels synchronised?
//!!! -> and view magnitudes array?
//
// - the paint thread needs to release the mutex occasionally so that
// cache positioning adjustments don't take forever.
//
// The cache covers a range from "somewhat before the start of the
// view" to "somewhat after the end of it", and only (more or less)
// the height of the view.  (Or is it better for it to cover the full
// height?)  It is always at full resolution -- 1 pixel per bin in
// both directions.  When drawing from cache, the GUI thread does the
// scaling.

//!!! and split into parent class (called e.g. DenseDataLayer) and
//subclass; parent has GUI thread, subclass has paint thread and most
//of the code.


void
SpectrogramLayer::paint(View *v, QPainter &paint, QRect rect) const
{
    // If the mutex for our cache is held, we should probably schedule
    // another update and return immediately.  The general cache mutex
    // should never be held long enough by any other thread for this
    // to be an issue.  (The paint thread should hold the general
    // cache mutex only long enough to look up the cache object in the
    // map, and then release it, retaining the specific mutex while it
    // paints.  The GUI thread should then never modify the cache
    // image without holding its specific mutex.)

    Profiler profiler("SpectrogramLayer::paint", true);

    std::cerr << "SpectrogramLayer::paint entering" << std::endl;

    QMutexLocker locker(&m_pixmapCacheMutex);

    rect = v->rect(); //!!!

    float ratio = float(v->getZoomLevel()) / float(getWindowIncrement());
    int imageWidth = lrintf(v->width() * ratio);

    std::cerr << "SpectrogramLayer::paint: view width = " << v->width() << ", ratio = " << ratio << ", imageWidth = " << imageWidth << std::endl;

    PixmapCache *cache = m_pixmapCaches[v];
    if (!cache) {
        cache = new PixmapCache;
        cache->pixmap = 0;
        m_pixmapCaches[v] = cache;
        cache->mutex.lock();
        cache->pixmap = new QImage(imageWidth, v->height(),
                                   QImage::Format_RGB32);
        cache->mutex.unlock();
#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "SpectrogramLayer::paint: Created new cache, size "
                  << imageWidth << "x" << v->height() << " ("
                  << imageWidth * v->height() * 4 << " bytes)" << std::endl;
#endif
        return; //!!! prod paint thread
    }

    long myStartFrame = v->getStartFrame();
    long cacheStartFrame = cache->startFrame;
    long xoff = (myStartFrame - cacheStartFrame) / getWindowIncrement();

    QRect sourceRect = QRect(lrintf(rect.x() * ratio) + xoff,
                             rect.y(),
                             lrintf(rect.width() * ratio),
                             rect.height());

    if (!cache->mutex.tryLock()) {
        std::cerr << "lock unavailable" << std::endl;

        paint.drawImage(rect,
                        cache->pixmap->copy(sourceRect)
                        .scaled(rect.size(),
                                Qt::IgnoreAspectRatio,
                                Qt::SmoothTransformation));

//        paint.drawImage(rect,// & cache->validArea,
//                        *cache->pixmap,
//                        rect);// & cache->validArea);
//        v->update(rect);
        return;
    }

    if (cache->pixmap->width() != imageWidth ||
        cache->pixmap->height() != v->height()) {
        QImage *newImage = new QImage
            (cache->pixmap->scaled(imageWidth, v->height(),
                                   Qt::IgnoreAspectRatio,
                                   Qt::SmoothTransformation));
#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "SpectrogramLayer::paint: Rescaling cache to size "
                  << imageWidth << "x" << v->height() << " ("
                  << imageWidth * v->height() * 4 << " bytes)" << std::endl;
#endif
        delete cache->pixmap;
        cache->pixmap = newImage;
    }

    // The cache has the correct resolution for the view in the y
    // axis, but with a resolution of one pixel per increment in the x
    // axis.  We may need to rescale when drawing.

    paint.setRenderHint(QPainter::SmoothPixmapTransform, true);

    //!!! not quite right in any case except integer ratio -- either
    //source or target rect will have edges at non-integral
    //coordinates

    std::cerr << "my start frame = " << myStartFrame << ", cache start frame = " << cacheStartFrame << std::endl;

    std::cerr << "ratio = " << ratio << " (zoom " << v->getZoomLevel()
              << ", incr " << getWindowIncrement() << "); source rect "
              << sourceRect.x() << "," << sourceRect.y()
              << " " << sourceRect.width() << "x" << sourceRect.height()
              << ", target rect "
              << rect.x() << "," << rect.y()
              << " " << rect.width() << "x" << rect.height()
              << " (image " << cache->pixmap->width() << "x"
              << cache->pixmap->height() << ")"
              << std::endl;

    paint.drawImage(rect,// & cache->validArea,
                    cache->pixmap->copy(sourceRect)
                    .scaled(rect.size(),
                            Qt::IgnoreAspectRatio,
                            Qt::SmoothTransformation));
//                    *cache->pixmap,
//                    sourceRect);// & cache->validArea);

    if (cache->startFrame != v->getStartFrame()) {
#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "SpectrogramLayer::paint(): Cache start frame "
                  << cache->startFrame << " differs from view start frame "
                  << v->getStartFrame() << std::endl;
#endif
        cache->mutex.unlock();
//        v->update(); //!!! and prod
        return;
    }

    if (!cache->validArea.contains(rect)) {
        //!!! don't want to be sending events; just want to flag up
        //that we need a repaint and let some higher power arrange to
        //do it
//        v->update(rect); //!!!??? prod paint thread
    }

//    paint.drawImage(rect & cache->validArea,
//                    cache->pixmap,
//                    rect & cache->validArea);

    cache->mutex.unlock();
}


void
SpectrogramLayer::PaintThread::run()
{
    while (!m_exiting) {

        std::set<View *> views;

        m_layer->m_pixmapCacheMutex.lock();
        for (ViewPixmapCache::iterator i = m_layer->m_pixmapCaches.begin();
             i != m_layer->m_pixmapCaches.end(); ++i) {
            views.insert(const_cast<View *>(i->first)); //!!!
        }
        m_layer->m_pixmapCacheMutex.unlock();

        bool workToDo = false;
        
        for (std::set<View *>::iterator vi = views.begin();
             vi != views.end(); ++vi) {
            
            if (m_layer->paintCache(*vi)) {
                if (!m_exiting) {
                    std::cerr << "Cache complete: asking view to update"
                              << std::endl;
                    (*vi)->update();
                }
            } else {
                workToDo = true;
            }

            if (m_exiting) break;
        }

        if (!m_exiting) {
            //!!! wait on condition
            if (workToDo) {
                // usleep(100);
                std::cerr << "SpectrogramLayer::PaintThread::run: still work to do, continuing" << std::endl;
            } else {
                sleep(10);
            }
        }
    }
}

// return true if no more work to do, or can do no more

bool
SpectrogramLayer::paintCache(View *v) const
{
    Profiler profiler("SpectrogramLayer::paintCache", true);

    m_pixmapCacheMutex.lock();
    
    PixmapCache *cacheptr = m_pixmapCaches[v];
    if (!cacheptr || !cacheptr->pixmap || cacheptr->pixmap->width() == 0) {
#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "SpectrogramLayer::paintCache(): No cache to paint onto"
                  << std::endl;
#endif
        m_pixmapCacheMutex.unlock();
        return false;
    }

    PixmapCache &cache = *cacheptr;
    QMutexLocker locker(&cache.mutex);
    m_pixmapCacheMutex.unlock();

#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "SpectrogramLayer::paintCache(): Have cache to paint onto"
                  << std::endl;
#endif

    QImage &image = *cache.pixmap; //!!! rename to cache.image

    const DenseTimeValueModel *model = m_model;
    if (!model || !model->isOK() || !model->isReady()) {
	return false;
    }

    //!!! mutex here -- we have the specific pixmap cache mutex held,
    //but only that one currently and there's no mutex for this stuff
    //in the other thread

    //!!! what a big pile of crap
    long startFrame = v->getStartFrame();
    int increment = getWindowIncrement(); // signed for arithmetic purposes
    size_t fftNominal = m_fftSize; // the user-specified fft size
    size_t fftSize = getFFTSize(v); // the actual fft size (maybe padded)
    FFTModel *fft = getFFTModel(v);
    int sr = model->getSampleRate();
    size_t fmin = m_minFrequency;
    size_t fmax = m_maxFrequency;
    FrequencyScale frequencyScale = m_frequencyScale;
    BinDisplay binDisplay = m_binDisplay;
    float threshold = m_threshold;
    bool normalizeColumns = m_normalizeColumns;
    bool normalizeVisibleArea = m_normalizeVisibleArea;
    ColourScale colourScale = m_colourScale;
    float gain = m_gain;
    const Palette &palette = m_palette;
    int zpl = getZeroPadLevel(v) + 1;

    if (!fft) {
	std::cerr << "ERROR: SpectrogramLayer::paintCache(): No FFT model, returning" << std::endl;
	return true;
    }


    std::cerr << "SpectrogramLayer::paintCache: start frame "
              << startFrame << ", increment " << increment << std::endl;


    int w = image.width();
    int h = image.height();


    // Establish rect to paint.  We want to paint a not-too-large area
    // that is not known to be valid, adjacent to an area that is
    // known to be valid, such that the resulting known-valid area is
    // rectangular still.  This doesn't really do that.
    
    QRect rect = QRect(0, 0, w, h);

    QPainter paint(cache.pixmap);
    
#ifdef DEBUG_SPECTROGRAM_REPAINT
    std::cerr << "SpectrogramLayer::paintCache(): m_model is " << model << ", window increment " << increment << std::endl;
    
    std::cerr << "rect is " << rect.x() << "," << rect.y() << " " << rect.width() << "x" << rect.height() << std::endl;
#endif

    if (startFrame < 0) m_candidateFillStartFrame = 0;
    else m_candidateFillStartFrame = startFrame;

/*
    if (isLayerDormant(v)) {
	std::cerr << "SpectrogramLayer::paintCache(): Layer is dormant, making it undormant again" << std::endl;
    }

    // Need to do this even if !isLayerDormant, as that could mean v
    // is not in the dormancy map at all -- we need it to be present
    // and accountable for when determining whether we need the cache
    // in the cache-fill thread above.
    //!!! no longer use cache-fill thread
    const_cast<SpectrogramLayer *>(this)->Layer::setLayerDormant(v, false);
*/

#ifdef DEBUG_SPECTROGRAM_REPAINT
    std::cerr << "SpectrogramLayer::paintCache(): pixmap cache size " << w << "x" << h << std::endl;
    std::cerr << "SpectrogramLayer::paintCache(): pixmap cache valid area " << cache.validArea.x() << ", " << cache.validArea.y() << ", " << cache.validArea.width() << "x" << cache.validArea.height() << std::endl;
#endif

    bool recreateWholeCache = true;

    int x0 = rect.left();
    int x1 = rect.right() + 1;

    struct timeval tv;
    (void)gettimeofday(&tv, 0);
    RealTime mainPaintStart = RealTime::fromTimeval(tv);

    int paintBlockWidth = m_lastPaintBlockWidth;

    if (paintBlockWidth == 0) {
        paintBlockWidth = (300000 / increment);
    } else {
        RealTime lastTime = m_lastPaintTime;
        while (lastTime > RealTime::fromMilliseconds(200) &&
               paintBlockWidth > 50) {
            paintBlockWidth /= 2;
            lastTime = lastTime / 2;
        }
        while (lastTime < RealTime::fromMilliseconds(90) &&
               paintBlockWidth < 1500) {
            paintBlockWidth *= 2;
            lastTime = lastTime * 2;
        }
    }

    if (paintBlockWidth < 20) paintBlockWidth = 20;

#ifdef DEBUG_SPECTROGRAM_REPAINT
    std::cerr << "[" << this << "]: last paint width: " << m_lastPaintBlockWidth << ", last paint time: " << m_lastPaintTime << ", new paint width: " << paintBlockWidth << std::endl;
#endif

    recreateWholeCache = checkAndScrollCache(cache, paint,
                                             startFrame, increment,
                                             x0, x1);

    selectPaintStrip(cache, x0, x1, paintBlockWidth);

    // We always paint the full height when refreshing the cache.
    // Smaller heights can be used when painting from cache, but we
    // want to ensure the cache is coherent without having to worry
    // about vertical matching of required and valid areas as well as
    // horizontal.

//    int h = v->height();
//    int w = x1 - x0;

#ifdef DEBUG_SPECTROGRAM_REPAINT
    std::cerr << "x0 " << x0 << ", x1 " << x1 << ", w " << w << ", h " << h << std::endl;
#endif

//    if (m_drawBuffer.width() < w || m_drawBuffer.height() < h) {
//        m_drawBuffer = QImage(w, h, QImage::Format_RGB32);
//    }

//    m_drawBuffer.fill(m_palette.getColour(0).rgb());

    // Set minFreq and maxFreq to the frequency extents of the possibly
    // zero-padded visible bin range, and displayMinFreq and displayMaxFreq
    // to the actual scale frequency extents (presumably not zero padded).

    // If we are zero padding, we want to use the zero-padded
    // equivalents of the bins that we would be using if not zero
    // padded, to avoid spaces at the top and bottom of the display.

    //!!! --> we weren't actually using minFreq or maxFreq -- so just
    // set our new fmin/fmax to the display extents

    // Note fftSize is the actual zero-padded fft size, fftNominal the
    // nominal fft size.
    
    size_t maxbin = fftNominal / 2;
    if (fmax > 0) {
	maxbin = int((double(fmax) * fftNominal) / sr + 0.001);
	if (maxbin > fftNominal / 2) maxbin = fftNominal / 2;
    }

    size_t minbin = 1;
    if (fmin > 0) {
	minbin = int((double(fmin) * fftNominal) / sr + 0.001);
	if (minbin < 1) minbin = 1;
	if (minbin >= maxbin) minbin = maxbin - 1;
    }

    minbin = minbin * zpl;
    maxbin = (maxbin + 1) * zpl - 1;

    fmin = (float(minbin) * sr) / fftNominal;
    fmax = (float(maxbin) * sr) / fftNominal;

    float ymag[h];
    float ydiv[h];
    float yval[maxbin + 1]; //!!! cache this?

    bool logarithmic = (frequencyScale == LogFrequencyScale);

    for (size_t q = minbin; q <= maxbin; ++q) {
        float f0 = (float(q) * sr) / fftSize;
        yval[q] = v->getYForFrequency(f0, fmin, fmax, logarithmic);
//        std::cerr << "min: " << minFreq << ", max: " << maxFreq << ", yval[" << q << "]: " << yval[q] << std::endl;
    }

    MagnitudeRange overallMag = m_viewMags[v];
//    bool overallMagChanged = false;

//    bool fftSuspended = false;

    bool interpolate = false;
    Preferences::SpectrogramSmoothing smoothing = 
        Preferences::getInstance()->getSpectrogramSmoothing();
    if (smoothing == Preferences::SpectrogramInterpolated ||
        smoothing == Preferences::SpectrogramZeroPaddedAndInterpolated) {
        if (binDisplay != PeakBins &&
            binDisplay != PeakFrequencies) {
            interpolate = true;
        }
    }

    bool runOutOfData = false;
    int runOutOfDataAt = x1;

    std::cerr << "painting from " << x0 << " to " << x1 << std::endl;

    for (int x = 0; x < (x1 - x0); ++x) {

        if (runOutOfData) break;

	for (int y = 0; y < h; ++y) {
	    ymag[y] = 0.f;
	    ydiv[y] = 0.f;
	}

        int col = (startFrame / increment) + x0 + x;

//        std::cerr << "x = " << x << ", col = " << col << std::endl;

	if (col >= int(fft->getWidth())) {
            continue;
	}

        if (!fft->isColumnAvailable(col)) {
#ifdef DEBUG_SPECTROGRAM_REPAINT
            std::cerr << "Met unavailable column at col " << col << std::endl;
#endif
            runOutOfData = true;
            runOutOfDataAt = x0 + x;
            break;
        }

/*            
            if (!fftSuspended) {
                fft->suspendWrites();
                fftSuspended = true;
            }
*/

        MagnitudeRange mag;

        FFTModel::PeakSet peaks;
        if (binDisplay == PeakFrequencies &&
            col < int(fft->getWidth()) - 1) {
            peaks = fft->getPeakFrequencies(FFTModel::AllPeaks,
                                            col,
                                            minbin, maxbin - 1);
        }

        for (size_t q = minbin; q < maxbin; ++q) {

            float y0 = yval[q + 1];
            float y1 = yval[q];

            if (binDisplay == PeakBins) {
                if (!fft->isLocalPeak(col, q)) continue;
            }
            if (binDisplay == PeakFrequencies) {
                if (peaks.find(q) == peaks.end()) continue;
            }
            
            if (threshold != 0.f &&
                !fft->isOverThreshold(col, q, threshold * (fftNominal/2))) {
                continue;
            }

            if (binDisplay == PeakFrequencies) {
                y0 = y1 = v->getYForFrequency
                    (peaks[q], fmin, fmax, logarithmic);
            }
		
            int y0i = int(y0 + 0.001);
            int y1i = int(y1);
            
            float value;
            
            if (colourScale == PhaseColourScale) {
                value = fft->getPhaseAt(col, q);
            } else if (normalizeColumns) {
                value = fft->getNormalizedMagnitudeAt(col, q);
                mag.sample(value);
                value *= gain;
            } else {
                value = fft->getMagnitudeAt(col, q) / (fftNominal/2);
                mag.sample(value);
                value *= gain;
            }

            if (interpolate) {
                    
                int ypi = y0i;
                if (q < maxbin - 1) ypi = int(yval[q + 2]);
                
                for (int y = ypi; y <= y1i; ++y) {
                    
                    if (y < 0 || y >= h) continue;
                    
                    float yprop = 1.f;
                    float iprop = yprop;
                    
                    if (ypi < y0i && y <= y0i) {
                        
                        float half = float(y0i - ypi) / 2;
                        float dist = y - (ypi + half);
                        
                        if (dist >= 0) {
                            iprop = (iprop * dist) / half;
                            ymag[y] += iprop * value;
                        }
                    } else {
                        if (y1i > y0i) {
                            
                            float half = float(y1i - y0i) / 2;
                            float dist = y - (y0i + half);
                            
                            if (dist >= 0) {
                                iprop = (iprop * (half - dist)) / half;
                            }
                        }
                        
                        ymag[y] += iprop * value;
                        ydiv[y] += yprop;
                    }
                }
                
            } else {
                
                for (int y = y0i; y <= y1i; ++y) {
                    
                    if (y < 0 || y >= h) continue;
                    
                    float yprop = 1.f;
                    if (y == y0i) yprop *= (y + 1) - y0;
                    if (y == y1i) yprop *= y1 - y;
                    
                    for (int y = y0i; y <= y1i; ++y) {
                        
                        if (y < 0 || y >= h) continue;
                        
                        float yprop = 1.f;
                        if (y == y0i) yprop *= (y + 1) - y0;
                        if (y == y1i) yprop *= y1 - y;
                        ymag[y] += yprop * value;
                        ydiv[y] += yprop;
                    }
                }
            }
        }
/*
            if (mag.isSet()) {

                if (s >= int(m_columnMags.size())) {
                    std::cerr << "INTERNAL ERROR: " << s << " >= "
                              << m_columnMags.size() << " at SpectrogramLayer.cpp:" << __LINE__ << std::endl;
                }

                m_columnMags[s].sample(mag);

                if (overallMag.sample(mag)) {
                    //!!! scaling would change here
                    overallMagChanged = true;
#ifdef DEBUG_SPECTROGRAM_REPAINT
                    std::cerr << "Overall mag changed (again?) at column " << s << ", to [" << overallMag.getMin() << "->" << overallMag.getMax() << "]" << std::endl;
#endif
                }
            }
*/

	for (int y = 0; y < h; ++y) {

	    if (ydiv[y] > 0.0) {

		unsigned char pixel = 0;

		float avg = ymag[y] / ydiv[y];
		pixel = getDisplayValue(v, avg); //!!!???

//		assert(x <= m_drawBuffer.width());
                assert(x <= w);
		QColor c = palette.getColour(pixel);

                if (x0 + x >= w) {
                    std::cerr << "INTERNAL ERROR: " << x0 << "+" 
                              << x << " >= " << w
                              << " at SpectrogramLayer.cpp:"
                              << __LINE__ << std::endl;
                    continue;
                }

                if (y >= h) {
                    std::cerr << "INTERNAL ERROR: " << y
                              << " >= " << h
                              << " at SpectrogramLayer.cpp:"
                              << __LINE__ << std::endl;
                    continue;
                }

                assert(x0 + x < w);
                assert(y < h);

		image.setPixel(x0 + x, y,
                               qRgb(c.red(), c.green(), c.blue()));
	    }
	}
    }
/*
    if (overallMagChanged) {
        m_viewMags[v] = overallMag;
#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "Overall mag is now [" << m_viewMags[v].getMin() << "->" << m_viewMags[v].getMax() << "] - will be updating" << std::endl;
#endif
    } else {
#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "Overall mag unchanged at [" << m_viewMags[v].getMin() << "->" << m_viewMags[v].getMax() << "]" << std::endl;
#endif
    }
*/

    if (runOutOfData) {
        std::cerr << "ran out of data, setting x1 to " << runOutOfDataAt
                  << std::endl;
        x1 = runOutOfDataAt;
    }

    if (cache.validArea.width() > 0) {
        
        int vx0 = 0, vx1 = 0;
        vx0 = cache.validArea.x();
        vx1 = cache.validArea.x() + cache.validArea.width();

        std::cerr << "set cache valid region from "
                  << cache.validArea.x() << " -> " << cache.validArea.x() + cache.validArea.width();
        
        cache.validArea = QRect
            (std::min(vx0, x0), cache.validArea.y(),
             std::max(vx1 - std::min(vx0, x0),
                       x1 - std::min(vx0, x0)),
             cache.validArea.height());

        std::cerr << " to "
                  << cache.validArea.x() << " -> " << cache.validArea.x() + cache.validArea.width()
                  << std::endl;
        
    } else {
        
        cache.validArea = QRect(x0, 0, x1 - x0, h);

        std::cerr << "set cache valid region from empty to "
                  << cache.validArea.x() << " -> " << cache.validArea.x() + cache.validArea.width()
                  << std::endl;
    }
        
/*
    Profiler profiler2("SpectrogramLayer::paintCache: draw image", true);

#ifdef DEBUG_SPECTROGRAM_REPAINT
    std::cerr << "Painting " << w << "x" << rect.height()
              << " from draw buffer at " << 0 << "," << rect.y()
              << " to window at " << x0 << "," << rect.y() << std::endl;
#endif

    paint.drawImage(x0, rect.y(), m_drawBuffer, 0, rect.y(), w, rect.height());

    if (recreateWholeCache) {
//	cache.pixmap = QPixmap(v->width(), h);
        cache.pixmap = QImage(v->width(), h, QImage::Format_RGB32);
    }

#ifdef DEBUG_SPECTROGRAM_REPAINT
    std::cerr << "Painting " << w << "x" << h
              << " from draw buffer at " << 0 << "," << 0
              << " to cache at " << x0 << "," << 0 << std::endl;
#endif

    QPainter cachePainter(&cache.pixmap);
    cachePainter.drawImage(x0, 0, m_drawBuffer, 0, 0, w, h);
    cachePainter.end();
*/
/*
    if (!m_normalizeVisibleArea || !overallMagChanged) {
*/  
        cache.startFrame = startFrame;

        bool morePaintingRequired = false;

        if (cache.validArea.x() > 0) {
#ifdef DEBUG_SPECTROGRAM_REPAINT
            std::cerr << "SpectrogramLayer::paintCache() updating left (0, "
                      << cache.validArea.x() << ")" << std::endl;
#endif
//            v->update(0, 0, cache.validArea.x(), h);
            morePaintingRequired = true;
        }
        
        if (cache.validArea.x() + cache.validArea.width() <
            image.width()) {
#ifdef DEBUG_SPECTROGRAM_REPAINT
            std::cerr << "SpectrogramLayer::paintCache() updating right ("
                      << cache.validArea.x() + cache.validArea.width()
                      << ", "
                      << image.width() - (cache.validArea.x() +
                                                 cache.validArea.width())
                      << ")" << std::endl;
#endif
//            v->update(cache.validArea.x() + cache.validArea.width(),
//                      0,
//                      image.width() - (cache.validArea.x() +
//                                              cache.validArea.width()),
//                      h);
            morePaintingRequired = true;
        }
/*
    } else {
        // overallMagChanged
        cache.validArea = QRect();
        morePaintingRequired = true;
//        v->update();
    }
*/
//    illuminateLocalFeatures(v, paint);

#ifdef DEBUG_SPECTROGRAM_REPAINT
    std::cerr << "SpectrogramLayer::paintCache() returning" << std::endl;
#endif

    paint.end();

    m_lastPaintBlockWidth = paintBlockWidth;
    (void)gettimeofday(&tv, 0);
    m_lastPaintTime = RealTime::fromTimeval(tv) - mainPaintStart;

    return !morePaintingRequired;

//    if (fftSuspended) fft->resume();
}

bool
SpectrogramLayer::checkAndScrollCache(PixmapCache &cache, QPainter &paint,
                                      long startFrame, int increment,
                                      int &x0, int &x1) const
{
    int w = cache.pixmap->width();

    if (cache.validArea.width() == 0) {
        x0 = 0;
        x1 = w;
        return true; // redraw everything
    } 

    //!!! no, the gui thread will handle resizes -- we just draw
    //the area that's available in the cache.  If the image is
    //enlarged, our valid area should remain the same and we'll
    //pick up on the discrepancy naturally (we hope)
//	if (cache.pixmap->width() == v->width() &&
//	    cache.pixmap->height() == v->height()) {

    if (cache.startFrame / increment == startFrame / increment &&
        cache.validArea.x() <= x0 &&
        cache.validArea.x() + cache.validArea.width() >= x1) {
	    
#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "SpectrogramLayer: pixmap cache good" << std::endl;
#endif

        //!!! set a flag to that effect?

        x1 = x0;
        return false;

    } else {

#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "SpectrogramLayer: pixmap cache partially OK" << std::endl;
#endif

        int dx = cache.startFrame / increment - startFrame / increment;

#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "SpectrogramLayer: dx = " << dx << " (pixmap cache " << cache.pixmap->width() << "x" << cache.pixmap->height() << ")" << std::endl;
#endif

        if (dx != 0 && dx > -w && dx < w) {

//#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).

            //!!! Need a utility function for this

            //!!! test again on Win and OS/X for images (above
            //comment applies to pixmaps)

            //!!! indeed, test again on linux for images too
            //-- I bet it doesn't work

            std::cerr << "SpectrogramLayer: copying from " << 0
                      << " to " << dx << std::endl;

            static QImage *tmp = 0; //!!! would need to be thread-local
            if (!tmp ||
                tmp->width() != w ||
                tmp->height() != cache.pixmap->height()) {
                delete tmp;
                tmp = new QImage(w,
                                 cache.pixmap->height(),
                                 QImage::Format_RGB32);
            }
            QPainter tmpPainter;
            tmpPainter.begin(tmp);
            tmpPainter.drawImage(0, 0, *cache.pixmap);
            tmpPainter.end();
            paint.drawImage(dx, 0, *tmp);
//#else
//                    paint.drawImage(dx, 0, image); //!!! see above
//#endif

            int px = cache.validArea.x();
            int pw = cache.validArea.width();

            if (dx < 0) {
                x0 = w + dx;
                x1 = w;
                px += dx;
                if (px < 0) {
                    pw += px;
                    px = 0;
                    if (pw < 0) pw = 0;
                }
            } else {
                x0 = 0;
                x1 = dx;
                px += dx;
                if (px + pw > w) {
                    pw = int(w) - px;
                    if (pw < 0) pw = 0;
                }
            }
                    
            cache.validArea =
                QRect(px, cache.validArea.y(),
                      pw, cache.validArea.height());
        }
    }
//	} else {
//#ifdef DEBUG_SPECTROGRAM_REPAINT
//	    std::cerr << "SpectrogramLayer: pixmap cache useless" << std::endl;
//            if (cache.pixmap->width() != v->width()) {
//                std::cerr << "(cache width " << cache.pixmap->width()
//                          << " != " << v->width();
//            }
//            if (cache.pixmap->height() != v->height()) {
//                std::cerr << "(cache height " << cache.pixmap->height()
//                          << " != " << v->height();
//            }
//#endif
//            cache.validArea = QRect();
//	}

/*!!!
  if (updateViewMagnitudes(v)) {
  #ifdef DEBUG_SPECTROGRAM_REPAINT
  std::cerr << "SpectrogramLayer: magnitude range changed to [" << m_viewMags[v].getMin() << "->" << m_viewMags[v].getMax() << "]" << std::endl;
  #endif
  recreateWholeCache = true;
  } else {
  #ifdef DEBUG_SPECTROGRAM_REPAINT
  std::cerr << "No change in magnitude range [" << m_viewMags[v].getMin() << "->" << m_viewMags[v].getMax() << "]" << std::endl;
  #endif
  }
*/
    return false;
}

void
SpectrogramLayer::selectPaintStrip(PixmapCache &cache, int &x0, int &x1,
                                   int paintBlockWidth) const
{
    // This function narrows down the region [x0, x1) where x1 >= x0
    // to a strip of approximately paintBlockWidth width.

    if (x1 - x0 < paintBlockWidth * 3 / 2) return; // it'll do

    if (cache.validArea.width() > 0) {

        // If part of the cache is known to be valid, select a strip
        // immediately to left or right of the valid part

        int vx0 = 0, vx1 = 0; // valid extents
        vx0 = cache.validArea.x();
        vx1 = cache.validArea.x() + cache.validArea.width();
        
#ifdef DEBUG_SPECTROGRAM_REPAINT
        std::cerr << "x0 " << x0 << ", x1 " << x1 << ", vx0 " << vx0 << ", vx1 " << vx1 << ", paintBlockWidth " << paintBlockWidth << std::endl;
#endif            
        if (x0 < vx0) {
            if (x0 + paintBlockWidth < vx0) {
                x0 = vx0 - paintBlockWidth;
            }
            x1 = vx0;
        } else if (x0 >= vx1) {
            x0 = vx1;
            if (x1 > x0 + paintBlockWidth) {
                x1 = x0 + paintBlockWidth;
            }
        } else {
            // x0 is within the valid area
            if (x1 > vx1) {
                x0 = vx1;
                if (x0 + paintBlockWidth < x1) {
                    x1 = x0 + paintBlockWidth;
                }
            } else {
                x1 = x0; // it's all valid, paint nothing
            }
        }

    } else {

        // No existing valid area; start at the middle, unless x0 is
        // already to the left of frame 0

        //!!! no, for now just start at the middle always

        if (x1 > x0 + paintBlockWidth) {

//            int sfx = x1; // x for frame zero
//            if (startFrame < 0) sfx = v->getXForFrame(0);            //!!!

//            if (startFrame < 0) sfx = 
//            if (sfx >= x0 && sfx + paintBlockWidth <= x1) {
//                x0 = sfx;
//                x1 = x0 + paintBlockWidth;
//            } else {
                int mid = (x1 + x0) / 2;
                x0 = mid - paintBlockWidth/2;
                x1 = x0 + paintBlockWidth;
//            }
        }
    }

    std::cerr << "SpectrogramLayer::selectPaintStrip: returning " << x0 << " -> " << x1 << std::endl;
}

void
SpectrogramLayer::illuminateLocalFeatures(View *v, QPainter &paint) const
{
    QPoint localPos;
    if (!v->shouldIlluminateLocalFeatures(this, localPos) || !m_model) {
        return;
    }

//    std::cerr << "SpectrogramLayer: illuminateLocalFeatures("
//              << localPos.x() << "," << localPos.y() << ")" << std::endl;

    float s0, s1;
    float f0, f1;

    if (getXBinRange(v, localPos.x(), s0, s1) &&
        getYBinSourceRange(v, localPos.y(), f0, f1)) {
        
        int s0i = int(s0 + 0.001);
        int s1i = int(s1);
        
        int x0 = v->getXForFrame(s0i * getWindowIncrement());
        int x1 = v->getXForFrame((s1i + 1) * getWindowIncrement());

        int y1 = int(getYForFrequency(v, f1));
        int y0 = int(getYForFrequency(v, f0));
        
//        std::cerr << "SpectrogramLayer: illuminate "
//                  << x0 << "," << y1 << " -> " << x1 << "," << y0 << std::endl;
        
        paint.setPen(v->getForeground());

        //!!! should we be using paintCrosshairs for this?

        paint.drawRect(x0, y1, x1 - x0 + 1, y0 - y1 + 1);
    }
}

float
SpectrogramLayer::getYForFrequency(const View *v, float frequency) const
{
    return v->getYForFrequency(frequency,
			       getEffectiveMinFrequency(),
			       getEffectiveMaxFrequency(),
			       m_frequencyScale == LogFrequencyScale);
}

float
SpectrogramLayer::getFrequencyForY(const View *v, int y) const
{
    return v->getFrequencyForY(y,
			       getEffectiveMinFrequency(),
			       getEffectiveMaxFrequency(),
			       m_frequencyScale == LogFrequencyScale);
}

int
SpectrogramLayer::getCompletion(View *v) const
{
    if (m_updateTimer == 0) return 100;
    if (m_fftModels.find(v) == m_fftModels.end()) return 100;

    size_t completion = m_fftModels[v].first->getCompletion();
#ifdef DEBUG_SPECTROGRAM_REPAINT
    std::cerr << "SpectrogramLayer::getCompletion: completion = " << completion << std::endl;
#endif
    return completion;
}

bool
SpectrogramLayer::getValueExtents(float &min, float &max,
                                  bool &logarithmic, QString &unit) const
{
    if (!m_model) return false;

    int sr = m_model->getSampleRate();
    min = float(sr) / m_fftSize;
    max = float(sr) / 2;
    
    logarithmic = (m_frequencyScale == LogFrequencyScale);
    unit = "Hz";
    return true;
}

bool
SpectrogramLayer::getDisplayExtents(float &min, float &max) const
{
    min = getEffectiveMinFrequency();
    max = getEffectiveMaxFrequency();

//    std::cerr << "SpectrogramLayer::getDisplayExtents: " << min << "->" << max << std::endl;
    return true;
}    

bool
SpectrogramLayer::setDisplayExtents(float min, float max)
{
    if (!m_model) return false;

//    std::cerr << "SpectrogramLayer::setDisplayExtents: " << min << "->" << max << std::endl;

    if (min < 0) min = 0;
    if (max > m_model->getSampleRate()/2) max = m_model->getSampleRate()/2;
    
    size_t minf = lrintf(min);
    size_t maxf = lrintf(max);

    if (m_minFrequency == minf && m_maxFrequency == maxf) return true;

    invalidatePixmapCaches();
    invalidateMagnitudes();

    m_minFrequency = minf;
    m_maxFrequency = maxf;
    
    emit layerParametersChanged();

    int vs = getCurrentVerticalZoomStep();
    if (vs != m_lastEmittedZoomStep) {
        emit verticalZoomChanged();
        m_lastEmittedZoomStep = vs;
    }

    return true;
}

bool
SpectrogramLayer::getYScaleValue(const View *v, int y,
                                 float &value, QString &unit) const
{
    value = getFrequencyForY(v, y);
    unit = "Hz";
    return true;
}

bool
SpectrogramLayer::snapToFeatureFrame(View *, int &frame,
				     size_t &resolution,
				     SnapType snap) const
{
    resolution = getWindowIncrement();
    int left = (frame / resolution) * resolution;
    int right = left + resolution;

    switch (snap) {
    case SnapLeft:  frame = left;  break;
    case SnapRight: frame = right; break;
    case SnapNearest:
    case SnapNeighbouring:
	if (frame - left > right - frame) frame = right;
	else frame = left;
	break;
    }
    
    return true;
} 

void
SpectrogramLayer::measureDoubleClick(View *v, QMouseEvent *e)
{
    //!!! check cache consistency
    QMutexLocker locker(&m_pixmapCacheMutex);

    PixmapCache *cache = m_pixmapCaches[v];
    if (!cache || !cache->pixmap) return;

    std::cerr << "cache width: " << cache->pixmap->width() << ", height: "
              << cache->pixmap->height() << std::endl;

    //!!! lock

    QImage image = *cache->pixmap /*.toImage() */;

    ImageRegionFinder finder;
    QRect rect = finder.findRegionExtents(&image, e->pos());
    if (rect.isValid()) {
        MeasureRect mr;
        setMeasureRectFromPixrect(v, mr, rect);
        CommandHistory::getInstance()->addCommand
            (new AddMeasurementRectCommand(this, mr));
    }
}

bool
SpectrogramLayer::getCrosshairExtents(View *v, QPainter &paint,
                                      QPoint cursorPos,
                                      std::vector<QRect> &extents) const
{
    QRect vertical(cursorPos.x() - 12, 0, 12, v->height());
    extents.push_back(vertical);

    QRect horizontal(0, cursorPos.y(), cursorPos.x(), 1);
    extents.push_back(horizontal);

    int sw = getVerticalScaleWidth(v, paint);

    QRect freq(sw, cursorPos.y() - paint.fontMetrics().ascent() - 2,
               paint.fontMetrics().width("123456 Hz") + 2,
               paint.fontMetrics().height());
    extents.push_back(freq);

    QRect pitch(sw, cursorPos.y() + 2,
                paint.fontMetrics().width("C#10+50c") + 2,
                paint.fontMetrics().height());
    extents.push_back(pitch);

    QRect rt(cursorPos.x(),
             v->height() - paint.fontMetrics().height() - 2,
             paint.fontMetrics().width("1234.567 s"),
             paint.fontMetrics().height());
    extents.push_back(rt);

    int w(paint.fontMetrics().width("1234567890") + 2);
    QRect frame(cursorPos.x() - w - 2,
                v->height() - paint.fontMetrics().height() - 2,
                w,
                paint.fontMetrics().height());
    extents.push_back(frame);

    return true;
}

void
SpectrogramLayer::paintCrosshairs(View *v, QPainter &paint,
                                  QPoint cursorPos) const
{
    paint.save();

    int sw = getVerticalScaleWidth(v, paint);

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

    paint.drawLine(0, cursorPos.y(), cursorPos.x() - 1, cursorPos.y());
    paint.drawLine(cursorPos.x(), 0, cursorPos.x(), v->height());
    
    float fundamental = getFrequencyForY(v, cursorPos.y());

    v->drawVisibleText(paint,
                       sw + 2,
                       cursorPos.y() - 2,
                       QString("%1 Hz").arg(fundamental),
                       View::OutlinedText);

    if (Pitch::isFrequencyInMidiRange(fundamental)) {
        QString pitchLabel = Pitch::getPitchLabelForFrequency(fundamental);
        v->drawVisibleText(paint,
                           sw + 2,
                           cursorPos.y() + paint.fontMetrics().ascent() + 2,
                           pitchLabel,
                           View::OutlinedText);
    }

    long frame = v->getFrameForX(cursorPos.x());
    RealTime rt = RealTime::frame2RealTime(frame, m_model->getSampleRate());
    QString rtLabel = QString("%1 s").arg(rt.toText(true).c_str());
    QString frameLabel = QString("%1").arg(frame);
    v->drawVisibleText(paint,
                       cursorPos.x() - paint.fontMetrics().width(frameLabel) - 2,
                       v->height() - 2,
                       frameLabel,
                       View::OutlinedText);
    v->drawVisibleText(paint,
                       cursorPos.x() + 2,
                       v->height() - 2,
                       rtLabel,
                       View::OutlinedText);

    int harmonic = 2;

    while (harmonic < 100) {

        float hy = lrintf(getYForFrequency(v, fundamental * harmonic));
        if (hy < 0 || hy > v->height()) break;
        
        int len = 7;

        if (harmonic % 2 == 0) {
            if (harmonic % 4 == 0) {
                len = 12;
            } else {
                len = 10;
            }
        }

        paint.drawLine(cursorPos.x() - len,
                       int(hy),
                       cursorPos.x(),
                       int(hy));

        ++harmonic;
    }

    paint.restore();
}

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

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

    float magMin = 0, magMax = 0;
    float phaseMin = 0, phaseMax = 0;
    float freqMin = 0, freqMax = 0;
    float adjFreqMin = 0, adjFreqMax = 0;
    QString pitchMin, pitchMax;
    RealTime rtMin, rtMax;

    bool haveValues = false;

    if (!getXBinSourceRange(v, x, rtMin, rtMax)) {
	return "";
    }
    if (getXYBinSourceRange(v, x, y, magMin, magMax, phaseMin, phaseMax)) {
	haveValues = true;
    }

    QString adjFreqText = "", adjPitchText = "";

    if (m_binDisplay == PeakFrequencies) {

	if (!getAdjustedYBinSourceRange(v, x, y, freqMin, freqMax,
					adjFreqMin, adjFreqMax)) {
	    return "";
	}

	if (adjFreqMin != adjFreqMax) {
	    adjFreqText = tr("Peak Frequency:\t%1 - %2 Hz\n")
		.arg(adjFreqMin).arg(adjFreqMax);
	} else {
	    adjFreqText = tr("Peak Frequency:\t%1 Hz\n")
		.arg(adjFreqMin);
	}

	QString pmin = Pitch::getPitchLabelForFrequency(adjFreqMin);
	QString pmax = Pitch::getPitchLabelForFrequency(adjFreqMax);

	if (pmin != pmax) {
	    adjPitchText = tr("Peak Pitch:\t%3 - %4\n").arg(pmin).arg(pmax);
	} else {
	    adjPitchText = tr("Peak Pitch:\t%2\n").arg(pmin);
	}

    } else {
	
	if (!getYBinSourceRange(v, y, freqMin, freqMax)) return "";
    }

    QString text;

    if (rtMin != rtMax) {
	text += tr("Time:\t%1 - %2\n")
	    .arg(rtMin.toText(true).c_str())
	    .arg(rtMax.toText(true).c_str());
    } else {
	text += tr("Time:\t%1\n")
	    .arg(rtMin.toText(true).c_str());
    }

    if (freqMin != freqMax) {
	text += tr("%1Bin Frequency:\t%2 - %3 Hz\n%4Bin Pitch:\t%5 - %6\n")
	    .arg(adjFreqText)
	    .arg(freqMin)
	    .arg(freqMax)
	    .arg(adjPitchText)
	    .arg(Pitch::getPitchLabelForFrequency(freqMin))
	    .arg(Pitch::getPitchLabelForFrequency(freqMax));
    } else {
	text += tr("%1Bin Frequency:\t%2 Hz\n%3Bin Pitch:\t%4\n")
	    .arg(adjFreqText)
	    .arg(freqMin)
	    .arg(adjPitchText)
	    .arg(Pitch::getPitchLabelForFrequency(freqMin));
    }	

    if (haveValues) {
	float dbMin = AudioLevel::multiplier_to_dB(magMin);
	float dbMax = AudioLevel::multiplier_to_dB(magMax);
	QString dbMinString;
	QString dbMaxString;
	if (dbMin == AudioLevel::DB_FLOOR) {
	    dbMinString = tr("-Inf");
	} else {
	    dbMinString = QString("%1").arg(lrintf(dbMin));
	}
	if (dbMax == AudioLevel::DB_FLOOR) {
	    dbMaxString = tr("-Inf");
	} else {
	    dbMaxString = QString("%1").arg(lrintf(dbMax));
	}
	if (lrintf(dbMin) != lrintf(dbMax)) {
	    text += tr("dB:\t%1 - %2").arg(dbMinString).arg(dbMaxString);
	} else {
	    text += tr("dB:\t%1").arg(dbMinString);
	}
	if (phaseMin != phaseMax) {
	    text += tr("\nPhase:\t%1 - %2").arg(phaseMin).arg(phaseMax);
	} else {
	    text += tr("\nPhase:\t%1").arg(phaseMin);
	}
    }

    return text;
}

int
SpectrogramLayer::getColourScaleWidth(QPainter &paint) const
{
    int cw;

    cw = paint.fontMetrics().width("-80dB");

    return cw;
}

int
SpectrogramLayer::getVerticalScaleWidth(View *, QPainter &paint) const
{
    if (!m_model || !m_model->isOK()) return 0;

    int cw = getColourScaleWidth(paint);

    int tw = paint.fontMetrics().width(QString("%1")
				     .arg(m_maxFrequency > 0 ?
					  m_maxFrequency - 1 :
					  m_model->getSampleRate() / 2));

    int fw = paint.fontMetrics().width(tr("43Hz"));
    if (tw < fw) tw = fw;

    int tickw = (m_frequencyScale == LogFrequencyScale ? 10 : 4);
    
    return cw + tickw + tw + 13;
}

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

    Profiler profiler("SpectrogramLayer::paintVerticalScale", false);

    //!!! cache this?

    int h = rect.height(), w = rect.width();

    int tickw = (m_frequencyScale == LogFrequencyScale ? 10 : 4);
    int pkw = (m_frequencyScale == LogFrequencyScale ? 10 : 0);

    size_t bins = m_fftSize / 2;
    int sr = m_model->getSampleRate();

    if (m_maxFrequency > 0) {
	bins = int((double(m_maxFrequency) * m_fftSize) / sr + 0.1);
	if (bins > m_fftSize / 2) bins = m_fftSize / 2;
    }

    int cw = getColourScaleWidth(paint);
    int cbw = paint.fontMetrics().width("dB");

    int py = -1;
    int textHeight = paint.fontMetrics().height();
    int toff = -textHeight + paint.fontMetrics().ascent() + 2;

    if (h > textHeight * 3 + 10) {

        int topLines = 2;
        if (m_colourScale == PhaseColourScale) topLines = 1;

	int ch = h - textHeight * (topLines + 1) - 8;
//	paint.drawRect(4, textHeight + 4, cw - 1, ch + 1);
	paint.drawRect(4 + cw - cbw, textHeight * topLines + 4, cbw - 1, ch + 1);

	QString top, bottom;
        float min = m_viewMags[v].getMin();
        float max = m_viewMags[v].getMax();

        float dBmin = AudioLevel::multiplier_to_dB(min);
        float dBmax = AudioLevel::multiplier_to_dB(max);

        if (dBmax < -60.f) dBmax = -60.f;
        else top = QString("%1").arg(lrintf(dBmax));

        if (dBmin < dBmax - 60.f) dBmin = dBmax - 60.f;
        bottom = QString("%1").arg(lrintf(dBmin));

        //!!! & phase etc

        if (m_colourScale != PhaseColourScale) {
            paint.drawText((cw + 6 - paint.fontMetrics().width("dBFS")) / 2,
                           2 + textHeight + toff, "dBFS");
        }

//	paint.drawText((cw + 6 - paint.fontMetrics().width(top)) / 2,
	paint.drawText(3 + cw - cbw - paint.fontMetrics().width(top),
		       2 + textHeight * topLines + toff + textHeight/2, top);

	paint.drawText(3 + cw - cbw - paint.fontMetrics().width(bottom),
		       h + toff - 3 - textHeight/2, bottom);

	paint.save();
	paint.setBrush(Qt::NoBrush);

        int lasty = 0;
        int lastdb = 0;

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

            float dBval = dBmin + (((dBmax - dBmin) * i) / (ch - 1));
            int idb = int(dBval);

            float value = AudioLevel::dB_to_multiplier(dBval);
            int colour = getDisplayValue(v, value * m_gain);

	    paint.setPen(m_palette.getColour(colour));

            int y = textHeight * topLines + 4 + ch - i;

            paint.drawLine(5 + cw - cbw, y, cw + 2, y);

            if (i == 0) {
                lasty = y;
                lastdb = idb;
            } else if (i < ch - paint.fontMetrics().ascent() &&
                       idb != lastdb &&
                       ((abs(y - lasty) > textHeight && 
                         idb % 10 == 0) ||
                        (abs(y - lasty) > paint.fontMetrics().ascent() && 
                         idb % 5 == 0))) {
                paint.setPen(v->getBackground());
                QString text = QString("%1").arg(idb);
                paint.drawText(3 + cw - cbw - paint.fontMetrics().width(text),
                               y + toff + textHeight/2, text);
                paint.setPen(v->getForeground());
                paint.drawLine(5 + cw - cbw, y, 8 + cw - cbw, y);
                lasty = y;
                lastdb = idb;
            }
	}
	paint.restore();
    }

    paint.drawLine(cw + 7, 0, cw + 7, h);

    int bin = -1;

    for (int y = 0; y < v->height(); ++y) {

	float q0, q1;
	if (!getYBinRange(v, v->height() - y, q0, q1)) continue;

	int vy;

	if (int(q0) > bin) {
	    vy = y;
	    bin = int(q0);
	} else {
	    continue;
	}

	int freq = (sr * bin) / m_fftSize;

	if (py >= 0 && (vy - py) < textHeight - 1) {
	    if (m_frequencyScale == LinearFrequencyScale) {
		paint.drawLine(w - tickw, h - vy, w, h - vy);
	    }
	    continue;
	}

	QString text = QString("%1").arg(freq);
	if (bin == 1) text = tr("%1Hz").arg(freq); // bin 0 is DC
	paint.drawLine(cw + 7, h - vy, w - pkw - 1, h - vy);

	if (h - vy - textHeight >= -2) {
	    int tx = w - 3 - paint.fontMetrics().width(text) - std::max(tickw, pkw);
	    paint.drawText(tx, h - vy + toff, text);
	}

	py = vy;
    }

    if (m_frequencyScale == LogFrequencyScale) {

        // piano keyboard

	paint.drawLine(w - pkw - 1, 0, w - pkw - 1, h);

	float minf = getEffectiveMinFrequency();
	float maxf = getEffectiveMaxFrequency();

	int py = h, ppy = h;
	paint.setBrush(paint.pen().color());

	for (int i = 0; i < 128; ++i) {

	    float f = Pitch::getFrequencyForPitch(i);
	    int y = lrintf(v->getYForFrequency(f, minf, maxf, true));

            if (y < -2) break;
            if (y > h + 2) {
                continue;
            }

	    int n = (i % 12);

            if (n == 1) {
                // C# -- fill the C from here
                QColor col = Qt::gray;
                if (i == 61) { // filling middle C
                    col = Qt::blue;
                    col = col.light(150);
                }
                if (ppy - y > 2) {
                    paint.fillRect(w - pkw,
                                   y,
                                   pkw,
                                   (py + ppy) / 2 - y,
                                   col);
                }
            }

	    if (n == 1 || n == 3 || n == 6 || n == 8 || n == 10) {
		// black notes
		paint.drawLine(w - pkw, y, w, y);
		int rh = ((py - y) / 4) * 2;
		if (rh < 2) rh = 2;
		paint.drawRect(w - pkw, y - (py-y)/4, pkw/2, rh);
	    } else if (n == 0 || n == 5) {
		// C, F
		if (py < h) {
		    paint.drawLine(w - pkw, (y + py) / 2, w, (y + py) / 2);
		}
	    }

            ppy = py;
	    py = y;
	}
    }
}

class SpectrogramRangeMapper : public RangeMapper
{
public:
    SpectrogramRangeMapper(int sr, int /* fftsize */) :
        m_dist(float(sr) / 2),
        m_s2(sqrtf(sqrtf(2))) { }
    ~SpectrogramRangeMapper() { }
    
    virtual int getPositionForValue(float value) const {

        float dist = m_dist;
    
        int n = 0;

        while (dist > (value + 0.00001) && dist > 0.1f) {
            dist /= m_s2;
            ++n;
        }

        return n;
    }

    virtual float getValueForPosition(int position) const {

        // Vertical zoom step 0 shows the entire range from DC ->
        // Nyquist frequency.  Step 1 shows 2^(1/4) of the range of
        // step 0, and so on until the visible range is smaller than
        // the frequency step between bins at the current fft size.

        float dist = m_dist;
    
        int n = 0;
        while (n < position) {
            dist /= m_s2;
            ++n;
        }

        return dist;
    }
    
    virtual QString getUnit() const { return "Hz"; }

protected:
    float m_dist;
    float m_s2;
};

int
SpectrogramLayer::getVerticalZoomSteps(int &defaultStep) const
{
    if (!m_model) return 0;

    int sr = m_model->getSampleRate();

    SpectrogramRangeMapper mapper(sr, m_fftSize);

//    int maxStep = mapper.getPositionForValue((float(sr) / m_fftSize) + 0.001);
    int maxStep = mapper.getPositionForValue(0);
    int minStep = mapper.getPositionForValue(float(sr) / 2);

    size_t initialMax = m_initialMaxFrequency;
    if (initialMax == 0) initialMax = sr / 2;

    defaultStep = mapper.getPositionForValue(initialMax) - minStep;

//    std::cerr << "SpectrogramLayer::getVerticalZoomSteps: " << maxStep - minStep << " (" << maxStep <<"-" << minStep << "), default is " << defaultStep << " (from initial max freq " << initialMax << ")" << std::endl;

    return maxStep - minStep;
}

int
SpectrogramLayer::getCurrentVerticalZoomStep() const
{
    if (!m_model) return 0;

    float dmin, dmax;
    getDisplayExtents(dmin, dmax);
    
    SpectrogramRangeMapper mapper(m_model->getSampleRate(), m_fftSize);
    int n = mapper.getPositionForValue(dmax - dmin);
//    std::cerr << "SpectrogramLayer::getCurrentVerticalZoomStep: " << n << std::endl;
    return n;
}

void
SpectrogramLayer::setVerticalZoomStep(int step)
{
    if (!m_model) return;

    float dmin = m_minFrequency, dmax = m_maxFrequency;
//    getDisplayExtents(dmin, dmax);

//    std::cerr << "current range " << dmin << " -> " << dmax << ", range " << dmax-dmin << ", mid " << (dmax + dmin)/2 << std::endl;
    
    int sr = m_model->getSampleRate();
    SpectrogramRangeMapper mapper(sr, m_fftSize);
    float newdist = mapper.getValueForPosition(step);

    float newmin, newmax;

    if (m_frequencyScale == LogFrequencyScale) {

        // need to pick newmin and newmax such that
        //
        // (log(newmin) + log(newmax)) / 2 == logmid
        // and
        // newmax - newmin = newdist
        //
        // so log(newmax - newdist) + log(newmax) == 2logmid
        // log(newmax(newmax - newdist)) == 2logmid
        // newmax.newmax - newmax.newdist == exp(2logmid)
        // newmax^2 + (-newdist)newmax + -exp(2logmid) == 0
        // quadratic with a = 1, b = -newdist, c = -exp(2logmid), all known
        // 
        // positive root
        // newmax = (newdist + sqrt(newdist^2 + 4exp(2logmid))) / 2
        //
        // but logmid = (log(dmin) + log(dmax)) / 2
        // so exp(2logmid) = exp(log(dmin) + log(dmax))
        // = exp(log(dmin.dmax))
        // = dmin.dmax
        // so newmax = (newdist + sqrtf(newdist^2 + 4dmin.dmax)) / 2

        newmax = (newdist + sqrtf(newdist*newdist + 4*dmin*dmax)) / 2;
        newmin = newmax - newdist;

//        std::cerr << "newmin = " << newmin << ", newmax = " << newmax << std::endl;

    } else {
        float dmid = (dmax + dmin) / 2;
        newmin = dmid - newdist / 2;
        newmax = dmid + newdist / 2;
    }

    float mmin, mmax;
    mmin = 0;
    mmax = float(sr) / 2;
    
    if (newmin < mmin) {
        newmax += (mmin - newmin);
        newmin = mmin;
    }
    if (newmax > mmax) {
        newmax = mmax;
    }
    
//    std::cerr << "SpectrogramLayer::setVerticalZoomStep: " << step << ": " << newmin << " -> " << newmax << " (range " << newdist << ")" << std::endl;

    setMinFrequency(lrintf(newmin));
    setMaxFrequency(lrintf(newmax));
}

RangeMapper *
SpectrogramLayer::getNewVerticalZoomRangeMapper() const
{
    if (!m_model) return 0;
    return new SpectrogramRangeMapper(m_model->getSampleRate(), m_fftSize);
}

void
SpectrogramLayer::updateMeasureRectYCoords(View *v, const MeasureRect &r) const
{
    int y0 = 0;
    if (r.startY > 0.0) y0 = getYForFrequency(v, r.startY);
    
    int y1 = y0;
    if (r.endY > 0.0) y1 = getYForFrequency(v, r.endY);

//    std::cerr << "SpectrogramLayer::updateMeasureRectYCoords: start " << r.startY << " -> " << y0 << ", end " << r.endY << " -> " << y1 << std::endl;

    r.pixrect = QRect(r.pixrect.x(), y0, r.pixrect.width(), y1 - y0);
}

void
SpectrogramLayer::setMeasureRectYCoord(View *v, MeasureRect &r, bool start, int y) const
{
    if (start) {
        r.startY = getFrequencyForY(v, y);
        r.endY = r.startY;
    } else {
        r.endY = getFrequencyForY(v, y);
    }
//    std::cerr << "SpectrogramLayer::setMeasureRectYCoord: start " << r.startY << " <- " << y << ", end " << r.endY << " <- " << y << std::endl;

}

void
SpectrogramLayer::toXml(QTextStream &stream,
                        QString indent, QString extraAttributes) const
{
    QString s;
    
    s += QString("channel=\"%1\" "
		 "windowSize=\"%2\" "
		 "windowHopLevel=\"%3\" "
		 "gain=\"%4\" "
		 "threshold=\"%5\" ")
	.arg(m_channel)
	.arg(m_windowSize)
	.arg(m_windowHopLevel)
	.arg(m_gain)
	.arg(m_threshold);

    s += QString("minFrequency=\"%1\" "
		 "maxFrequency=\"%2\" "
		 "colourScale=\"%3\" "
		 "colourScheme=\"%4\" "
		 "colourRotation=\"%5\" "
		 "frequencyScale=\"%6\" "
		 "binDisplay=\"%7\" "
		 "normalizeColumns=\"%8\" "
                 "normalizeVisibleArea=\"%9\"")
	.arg(m_minFrequency)
	.arg(m_maxFrequency)
	.arg(m_colourScale)
	.arg(m_colourMap)
	.arg(m_colourRotation)
	.arg(m_frequencyScale)
	.arg(m_binDisplay)
	.arg(m_normalizeColumns ? "true" : "false")
        .arg(m_normalizeVisibleArea ? "true" : "false");

    Layer::toXml(stream, indent, extraAttributes + " " + s);
}

void
SpectrogramLayer::setProperties(const QXmlAttributes &attributes)
{
    bool ok = false;

    int channel = attributes.value("channel").toInt(&ok);
    if (ok) setChannel(channel);

    size_t windowSize = attributes.value("windowSize").toUInt(&ok);
    if (ok) setWindowSize(windowSize);

    size_t windowHopLevel = attributes.value("windowHopLevel").toUInt(&ok);
    if (ok) setWindowHopLevel(windowHopLevel);
    else {
        size_t windowOverlap = attributes.value("windowOverlap").toUInt(&ok);
        // a percentage value
        if (ok) {
            if (windowOverlap == 0) setWindowHopLevel(0);
            else if (windowOverlap == 25) setWindowHopLevel(1);
            else if (windowOverlap == 50) setWindowHopLevel(2);
            else if (windowOverlap == 75) setWindowHopLevel(3);
            else if (windowOverlap == 90) setWindowHopLevel(4);
        }
    }

    float gain = attributes.value("gain").toFloat(&ok);
    if (ok) setGain(gain);

    float threshold = attributes.value("threshold").toFloat(&ok);
    if (ok) setThreshold(threshold);

    size_t minFrequency = attributes.value("minFrequency").toUInt(&ok);
    if (ok) {
        std::cerr << "SpectrogramLayer::setProperties: setting min freq to " << minFrequency << std::endl;
        setMinFrequency(minFrequency);
    }

    size_t maxFrequency = attributes.value("maxFrequency").toUInt(&ok);
    if (ok) {
        std::cerr << "SpectrogramLayer::setProperties: setting max freq to " << maxFrequency << std::endl;
        setMaxFrequency(maxFrequency);
    }

    ColourScale colourScale = (ColourScale)
	attributes.value("colourScale").toInt(&ok);
    if (ok) setColourScale(colourScale);

    int colourMap = attributes.value("colourScheme").toInt(&ok);
    if (ok) setColourMap(colourMap);

    int colourRotation = attributes.value("colourRotation").toInt(&ok);
    if (ok) setColourRotation(colourRotation);

    FrequencyScale frequencyScale = (FrequencyScale)
	attributes.value("frequencyScale").toInt(&ok);
    if (ok) setFrequencyScale(frequencyScale);

    BinDisplay binDisplay = (BinDisplay)
	attributes.value("binDisplay").toInt(&ok);
    if (ok) setBinDisplay(binDisplay);

    bool normalizeColumns =
	(attributes.value("normalizeColumns").trimmed() == "true");
    setNormalizeColumns(normalizeColumns);

    bool normalizeVisibleArea =
	(attributes.value("normalizeVisibleArea").trimmed() == "true");
    setNormalizeVisibleArea(normalizeVisibleArea);
}