view widgets/Fader.cpp @ 1127:9fb8dfd7ce4c spectrogram-minor-refactor

Fix threshold in spectrogram -- it wasn't working in the last release.
There is a new protocol for this. Formerly the threshold parameter had a
range from -50dB to 0 with the default at -50, and -50 treated internally
as "no threshold". However, there was a hardcoded, hidden internal threshold
for spectrogram colour mapping at -80dB with anything below this being rounded
to zero. Now the threshold parameter has range -81 to -1 with the default
at -80, -81 is treated internally as "no threshold", and there is no hidden
internal threshold. So the default behaviour is the same as before, an
effective -80dB threshold, but it is now possible to change this in both
directions. Sessions reloaded from prior versions may look slightly different
because, if the session says there should be no threshold, there will now
actually be no threshold instead of having the hidden internal one.

Still need to do something in the UI to make it apparent that the -81dB
setting removes the threshold entirely. This is at least no worse than the
previous, also obscured, magic -50dB setting.

/* -*- 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),
    m_mousePressX(0),
    m_mousePressValue(0)
{
    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) {
	cerr << "Fader: Error loading pixmap" << endl;
    }

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

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

    QString clip_path = ":/icons/fader_knob_red.png";
    ok = m_clip.load(clip_path);
    if (ok == false) {
	cerr <<  "Error loading pixmap" << 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 = (float)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 = (float)AudioLevel::fader_to_dB
        (0, getMaxX(), AudioLevel::LongFader);
    float max = (float)AudioLevel::fader_to_dB
        (getMaxX(), getMaxX(), AudioLevel::LongFader);
    float deft = (float)AudioLevel::multiplier_to_dB(m_value);

    float dB = (float)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 = (float)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.f);
    } else {
	setValue(m_value / 1.f);
    }

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

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

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

void
Fader::setValue(float v)
{
    float max = (float)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 = (float)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));
	}
        cerr << "Fader: setting tooltip to \"" << text << "\"" << 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;
}