view widgets/LevelPanWidget.cpp @ 959:2633a1d73e39

Address #1214, layer import produces wrong layer type. We needed a more principled approach to making sure the format gets updated properly and the dialog elements are consistent (basically separating making the dialog elements consistent from subsequently updating the format). This change should provide that, though there may be gotchas still.

/* -*- 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 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 "LevelPanWidget.h"

#include <QPainter>
#include <QMouseEvent>
#include <QWheelEvent>

#include "layer/ColourMapper.h"
#include "base/AudioLevel.h"

#include <iostream>
#include <cmath>
#include <cassert>

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

static const int maxLevel = 4; // min is 0, may be mute or not depending on m_includeMute
static const int maxPan = 2; // range is -maxPan to maxPan

LevelPanWidget::LevelPanWidget(QWidget *parent) :
    QWidget(parent),
    m_level(maxLevel),
    m_pan(0),
    m_editable(true),
    m_includeMute(true)
{
}

LevelPanWidget::~LevelPanWidget()
{
}

QSize
LevelPanWidget::sizeHint() const
{
    static double ratio = 0.0;
    if (ratio == 0.0) {
        double baseEm;
#ifdef Q_OS_MAC
        baseEm = 17.0;
#else
        baseEm = 15.0;
#endif
        double em = QFontMetrics(QFont()).height();
        ratio = em / baseEm;
    }

    int pixels = 40;
    int scaled = int(pixels * ratio + 0.5);
    if (pixels != 0 && scaled == 0) scaled = 1;
    return QSize(scaled, scaled);
}

static int
db_to_level(double db)
{
    // Only if !m_includeMute, otherwise AudioLevel is used.
    // Levels are: +6 0 -6 -12 -20
    assert(maxLevel == 4);
    if (db > 3.) return 4;
    else if (db > -3.) return 3;
    else if (db > -9.) return 2;
    else if (db > -16.) return 1;
    else return 0;
}

static double
level_to_db(int level)
{
    // Only if !m_includeMute, otherwise AudioLevel is used.
    // Levels are: +6 0 -6 -12 -20
    assert(maxLevel == 4);
    if (level >= 4) return 6.;
    else if (level == 3) return 0.;
    else if (level == 2) return -6.;
    else if (level == 1) return -12.;
    else return -20.;
}

void
LevelPanWidget::setLevel(float flevel)
{
    int level;
    if (m_includeMute) {
        level = AudioLevel::multiplier_to_fader
            (flevel, maxLevel, AudioLevel::ShortFader);
    } else {
        level = db_to_level(AudioLevel::multiplier_to_dB(flevel));
    }
    if (level < 0) level = 0;
    if (level > maxLevel) level = maxLevel;
    if (level != m_level) {
	m_level = level;
	float convertsTo = getLevel();
	if (fabsf(convertsTo - flevel) > 1e-5) {
	    emitLevelChanged();
	}
	update();
    }
}

float
LevelPanWidget::getLevel() const
{
    if (m_includeMute) {
        return float(AudioLevel::fader_to_multiplier
                     (m_level, maxLevel, AudioLevel::ShortFader));
    } else {
        return float(AudioLevel::dB_to_multiplier(level_to_db(m_level)));
    }
}

void
LevelPanWidget::setPan(float pan)
{
    m_pan = int(round(pan * maxPan));
    if (m_pan < -maxPan) m_pan = -maxPan;
    if (m_pan > maxPan) m_pan = maxPan;
    update();
}

bool
LevelPanWidget::isEditable() const
{
    return m_editable;
}

bool
LevelPanWidget::includesMute() const
{
    return m_includeMute;
}

void
LevelPanWidget::setEditable(bool editable)
{
    m_editable = editable;
    update();
}

void
LevelPanWidget::setIncludeMute(bool include)
{
    m_includeMute = include;
    emitLevelChanged();
    update();
}

float
LevelPanWidget::getPan() const
{
    return float(m_pan) / float(maxPan);
}

void
LevelPanWidget::emitLevelChanged()
{
    cerr << "emitting levelChanged(" << getLevel() << ")" << endl;
    emit levelChanged(getLevel());
}

void
LevelPanWidget::emitPanChanged()
{
    cerr << "emitting panChanged(" << getPan() << ")" << endl;
    emit panChanged(getPan());
}

void
LevelPanWidget::mousePressEvent(QMouseEvent *e)
{
    mouseMoveEvent(e);
}

void
LevelPanWidget::mouseMoveEvent(QMouseEvent *e)
{
    if (!m_editable) return;
    
    int level, pan;
    toCell(rect(), e->pos(), level, pan);
    if (level == m_level && pan == m_pan) {
	return;
    }
    if (level != m_level) {
	m_level = level;
	emitLevelChanged();
    }
    if (pan != m_pan) {
	m_pan = pan;
	emitPanChanged();
    }
    update();
}

void
LevelPanWidget::mouseReleaseEvent(QMouseEvent *e)
{
    mouseMoveEvent(e);
}

void
LevelPanWidget::wheelEvent(QWheelEvent *e)
{
    if (e->modifiers() & Qt::ControlModifier) {
	if (e->delta() > 0) {
	    if (m_pan < maxPan) {
		++m_pan;
		emitPanChanged();
		update();
	    }
	} else {
	    if (m_pan > -maxPan) {
		--m_pan;
		emitPanChanged();
		update();
	    }
	}
    } else {
	if (e->delta() > 0) {
	    if (m_level < maxLevel) {
		++m_level;
		emitLevelChanged();
		update();
	    }
	} else {
	    if (m_level > 0) {
		--m_level;
		emitLevelChanged();
		update();
	    }
	}
    }
}

void
LevelPanWidget::toCell(QRectF rect, QPointF loc, int &level, int &pan) const
{
    double w = rect.width(), h = rect.height();

    int npan = maxPan * 2 + 1;
    int nlevel = maxLevel + 1;

    double wcell = w / npan, hcell = h / nlevel;

    level = int((h - (loc.y() - rect.y())) / hcell);
    if (level < 0) level = 0;
    if (level > maxLevel) level = maxLevel;

    pan = int((loc.x() - rect.x()) / wcell) - maxPan;
    if (pan < -maxPan) pan = -maxPan;
    if (pan > maxPan) pan = maxPan;
}

QSizeF
LevelPanWidget::cellSize(QRectF rect) const
{
    double w = rect.width(), h = rect.height();
    int npan = maxPan * 2 + 1;
    int nlevel = maxLevel + 1;
    double wcell = w / npan, hcell = h / nlevel;
    return QSizeF(wcell, hcell);
}

QPointF
LevelPanWidget::cellCentre(QRectF rect, int level, int pan) const
{
    QSizeF cs = cellSize(rect);
    return QPointF(rect.x() + cs.width() * (pan + maxPan) + cs.width() / 2.,
		   rect.y() + rect.height() - cs.height() * (level + 1) + cs.height() / 2.);
}

QSizeF
LevelPanWidget::cellLightSize(QRectF rect) const
{
    double extent = 3. / 4.;
    QSizeF cs = cellSize(rect);
    double m = std::min(cs.width(), cs.height());
    return QSizeF(m * extent, m * extent);
}

QRectF
LevelPanWidget::cellLightRect(QRectF rect, int level, int pan) const
{
    QSizeF cls = cellLightSize(rect);
    QPointF cc = cellCentre(rect, level, pan);
    return QRectF(cc.x() - cls.width() / 2., 
		  cc.y() - cls.height() / 2.,
		  cls.width(),
		  cls.height());
}

double
LevelPanWidget::thinLineWidth(QRectF rect) const
{
    double tw = ceil(rect.width() / (maxPan * 2. * 10.));
    double th = ceil(rect.height() / (maxLevel * 10.));
    return std::min(th, tw);
}

static QColor
level_to_colour(int level)
{
    assert(maxLevel == 4);
    if (level == 0) return Qt::black;
    else if (level == 1) return QColor(80, 0, 0);
    else if (level == 2) return QColor(160, 0, 0);
    else if (level == 3) return QColor(255, 0, 0);
    else return QColor(255, 255, 0);
}

void
LevelPanWidget::renderTo(QPaintDevice *dev, QRectF rect, bool asIfEditable) const
{
    QPainter paint(dev);

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

    QPen pen;

    double thin = thinLineWidth(rect);

    pen.setColor(QColor(127, 127, 127, 127));
    pen.setWidthF(cellLightSize(rect).width() + thin);
    pen.setCapStyle(Qt::RoundCap);
    paint.setPen(pen);

    for (int pan = -maxPan; pan <= maxPan; ++pan) {
	paint.drawLine(cellCentre(rect, 0, pan), cellCentre(rect, maxLevel, pan));
    }

    if (isEnabled()) {
	pen.setColor(Qt::black);
    } else {
	pen.setColor(Qt::darkGray);
    }

    if (!asIfEditable && m_includeMute && m_level == 0) {
        pen.setWidthF(thin * 2);
        pen.setCapStyle(Qt::RoundCap);
        paint.setPen(pen);
        paint.drawLine(cellCentre(rect, 0, -maxPan),
                       cellCentre(rect, maxLevel, maxPan));
        paint.drawLine(cellCentre(rect, maxLevel, -maxPan),
                       cellCentre(rect, 0, maxPan));
        return;
    }
    
    pen.setWidthF(thin);
    pen.setCapStyle(Qt::FlatCap);
    paint.setPen(pen);
    
    for (int level = 0; level <= m_level; ++level) {
	if (isEnabled()) {
	    paint.setBrush(level_to_colour(level));
	}
	QRectF clr = cellLightRect(rect, level, m_pan);
	if (m_includeMute && m_level == 0) {
	    paint.drawLine(clr.topLeft(), clr.bottomRight());
	    paint.drawLine(clr.bottomLeft(), clr.topRight());
	} else {
	    paint.drawEllipse(clr);
	}
    }
}

void
LevelPanWidget::paintEvent(QPaintEvent *)
{
    renderTo(this, rect(), m_editable);
}