view widgets/Fader.cpp @ 349:369a197737c7

* Various fixes to object lifetime management, particularly in the spectrum
  layer and for notification of main model deletion.
  The main purpose of this is to improve the behaviour of the spectrum, but I
  think it may also help with #1840922 Various crashes in Layer Summary window.

/* -*- 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.
*/

/**
 * Horizontal audio fader and meter widget.
 *
 * Based on the vertical fader and meter widget from the Hydrogen drum
 * machine.  (Any poor taste that has crept in during the
 * modifications for this application is entirely my own, however.)
 * The following copyright notice applies to code from this file, and
 * also to the files in icons/fader_*.png (also modified by me). --cc
 */

/**
 * Hydrogen
 * Copyright(c) 2002-2005 by Alex >Comix< Cominu [[e-mail]]
 * http://www.hydrogen-music.org
 */


#include "Fader.h"

#include "base/AudioLevel.h"

#include <QMouseEvent>
#include <QPixmap>
#include <QWheelEvent>
#include <QPaintEvent>
#include <QPainter>
#include <QInputDialog>

#include <iostream>

Fader::Fader(QWidget *parent, bool withoutKnob) :
    QWidget(parent),
    m_withoutKnob(withoutKnob),
    m_value(1.0),
    m_peakLeft(0.0),
    m_peakRight(0.0),
    m_mousePressed(false)
{
    setMinimumSize(116, 23);
    setMaximumSize(116, 23);
    resize(116, 23);

    QString background_path = ":/icons/fader_background.png";
    bool ok = m_back.load(background_path);
    if (ok == false) {
	std::cerr << "Fader: Error loading pixmap" << std::endl;
    }

    QString leds_path = ":/icons/fader_leds.png";
    ok = m_leds.load(leds_path);
    if (ok == false) {
	std::cerr <<  "Error loading pixmap" << std::endl;
    }

    QString knob_path = ":/icons/fader_knob.png";
    ok = m_knob.load(knob_path);
    if (ok == false) {
	std::cerr <<  "Error loading pixmap" << std::endl;
    }

    QString clip_path = ":/icons/fader_knob_red.png";
    ok = m_clip.load(clip_path);
    if (ok == false) {
	std::cerr <<  "Error loading pixmap" << std::endl;
    }
}

Fader::~Fader()
{

}

void
Fader::mouseMoveEvent(QMouseEvent *ev)
{
    if (ev->button() == Qt::MidButton) {
        setValue(1.0);
        emit valueChanged(1.0);
        update();
        ev->accept();
        return;
    }
    if (!m_mousePressed) return;

    int x = ev->x();
    int diff = x - m_mousePressX;
    if (diff == 0) return;

    int vx = AudioLevel::multiplier_to_fader
        (m_mousePressValue, getMaxX(), AudioLevel::LongFader);

    vx += diff;

    if (vx > getMaxX()) vx = getMaxX();
    if (vx < 0) vx = 0;

    float fval = AudioLevel::fader_to_multiplier
	(vx, getMaxX(), AudioLevel::LongFader);

    setValue(fval);
    emit valueChanged(fval);
    ev->accept();
}


void
Fader::mouseReleaseEvent(QMouseEvent *ev)
{
    if (m_mousePressed) {
        mouseMoveEvent(ev);
        m_mousePressed = false;
    }
}

void
Fader::mouseDoubleClickEvent(QMouseEvent *)
{
    bool ok = false;
    float min = AudioLevel::fader_to_dB
        (0, getMaxX(), AudioLevel::LongFader);
    float max = AudioLevel::fader_to_dB
        (getMaxX(), getMaxX(), AudioLevel::LongFader);
    float deft = AudioLevel::multiplier_to_dB(m_value);

    float dB = QInputDialog::getDouble
        (this,
         tr("Enter new fader level"),
         tr("New fader level, from %1 to %2 dBFS:").arg(min).arg(max),
         deft, min, max, 3, &ok);

    if (ok) {
        float value = AudioLevel::dB_to_multiplier(dB);
        setValue(value);
        emit valueChanged(value);
        update();
    }
}

void
Fader::mousePressEvent(QMouseEvent *ev)
{
    if (ev->button() == Qt::MidButton ||
        ((ev->button() == Qt::LeftButton) &&
         (ev->modifiers() & Qt::ControlModifier))) {
        setValue(1.0);
        emit valueChanged(1.0);
        update();
        return;
    }

    if (ev->button() != Qt::LeftButton) return;
    m_mousePressed = true;
    m_mousePressX = ev->x();
    m_mousePressValue = getValue();
}


void
Fader::wheelEvent(QWheelEvent *ev)
{
    ev->accept();

    //!!! needs improvement

    if (ev->delta() > 0) {
	setValue(m_value * 1.1);
    } else {
	setValue(m_value / 1.1);
    }

    update();
    emit valueChanged(getValue());
}

void
Fader::enterEvent(QEvent *)
{
    emit mouseEntered();
}

void
Fader::leaveEvent(QEvent *)
{
    emit mouseLeft();
}

void
Fader::setValue(float v)
{
    float max = AudioLevel::dB_to_multiplier(10.0);

    if (v > max) {
	v = max;
    } else if (v < 0.0) {
	v = 0.0;
    }

    if (m_value != v) {
	m_value = v;
	float db = AudioLevel::multiplier_to_dB(m_value);
        QString text;
	if (db <= AudioLevel::DB_FLOOR) {
            text = tr("Level: Off");
	} else {
            text = tr("Level: %1%2.%3%4 dB")
                .arg(db < 0.0 ? "-" : "")
                .arg(abs(int(db)))
                .arg(abs(int(db * 10.0) % 10))
                .arg(abs(int(db * 100.0) % 10));
	}
        std::cerr << "Fader: setting tooltip to \"" << text.toStdString() << "\"" << std::endl;
        QWidget::setToolTip(text);
	update();
    }
}


float
Fader::getValue()
{
    return m_value;
}



void
Fader::setPeakLeft(float peak)
{
    if (this->m_peakLeft != peak) {
	this->m_peakLeft = peak;
	update();
    }
}


void
Fader::setPeakRight(float peak) 
{
    if (this->m_peakRight != peak) {
	this->m_peakRight = peak;
	update();
    }
}


void
Fader::paintEvent(QPaintEvent *)
{
    QPainter painter(this);

    // background
    painter.drawPixmap(rect(), m_back, QRect(0, 0, 116, 23));

    int offset_L = AudioLevel::multiplier_to_fader(m_peakLeft, 116,
						   AudioLevel::IEC268LongMeter);

    painter.drawPixmap(QRect(0, 0, offset_L, 11), m_leds,
		       QRect(0, 0, offset_L, 11));

    int offset_R = AudioLevel::multiplier_to_fader(m_peakRight, 116,
						   AudioLevel::IEC268LongMeter);

    painter.drawPixmap(QRect(0, 11, offset_R, 11), m_leds,
		       QRect(0, 11, offset_R, 11));

    if (m_withoutKnob == false) {

	static const uint knob_width = 29;
	static const uint knob_height = 9;

	int x = AudioLevel::multiplier_to_fader(m_value, 116 - knob_width,
						AudioLevel::LongFader);

	bool clipping = (m_peakLeft > 1.0 || m_peakRight > 1.0);

	painter.drawPixmap(QRect(x, 7, knob_width, knob_height),
			   clipping ? m_clip : m_knob,
			   QRect(0, 0, knob_width, knob_height));
    }
}

int
Fader::getMaxX() const
{
    return 116 - 12;
}