view widgets/LEDButton.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.
*/

/*
    This is a modified version of a source file from the KDE
    libraries.  Copyright (c) 1998-2004 Jörg Habenicht, Richard J
    Moore, Chris Cannam and others, distributed under the GNU Lesser
    General Public License.

    Ported to Qt4 by Chris Cannam.
*/


#include "LEDButton.h"

#include <QPainter>
#include <QImage>
#include <QColor>
#include <QMouseEvent>

#include <iostream>


class LEDButton::LEDButtonPrivate
{
    friend class LEDButton;

    int dark_factor;
    QColor offcolor;
};


LEDButton::LEDButton(QWidget *parent) :
    QWidget(parent),
    led_state(true)
{
    QColor col(Qt::green);
    d = new LEDButton::LEDButtonPrivate;
    d->dark_factor = 300;
    d->offcolor = col.dark(300);
    
    setColor(col);
}


LEDButton::LEDButton(const QColor& col, QWidget *parent) :
    QWidget(parent),
    led_state(true)
{
    d = new LEDButton::LEDButtonPrivate;
    d->dark_factor = 300;
    d->offcolor = col.dark(300);

    setColor(col);
}

LEDButton::LEDButton(const QColor& col, bool state, QWidget *parent) :
    QWidget(parent),
    led_state(state)
{
    d = new LEDButton::LEDButtonPrivate;
    d->dark_factor = 300;
    d->offcolor = col.dark(300);

    setColor(col);
}

LEDButton::~LEDButton()
{
    delete d;
}

void
LEDButton::mousePressEvent(QMouseEvent *e)
{
    cerr << "LEDButton(" << this << ")::mousePressEvent" << endl;

    if (e->buttons() & Qt::LeftButton) {
	toggle();
	bool newState = state();
	SVDEBUG << "emitting new state " << newState << endl;
	emit stateChanged(newState);
    }
}

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

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

void
LEDButton::paintEvent(QPaintEvent *)
{
    QPainter paint;
    QColor color;
    QBrush brush;
    QPen pen;
		
    // First of all we want to know what area should be updated
    // Initialize coordinates, width, and height of the LED
    int	width = this->width();

    // Make sure the LED is round!
    if (width > this->height())
	width = this->height();
    width -= 2; // leave one pixel border
    if (width < 0) 
	width = 0;

    paint.begin(this);

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

    // Set the color of the LED according to given parameters
    color = (led_state) ? led_color : d->offcolor;

    // Set the brush to SolidPattern, this fills the entire area
    // of the ellipse which is drawn first
    brush.setStyle(Qt::SolidPattern);
    brush.setColor(color);
    paint.setBrush(brush);

    // Draws a "flat" LED with the given color:
    paint.drawEllipse( 1, 1, width - 2, width - 2 );

    // Draw the bright light spot of the LED now, using modified "old"
    // painter routine taken from KDEUI´s LEDButton widget:

    // Setting the new width of the pen is essential to avoid "pixelized"
    // shadow like it can be observed with the old LED code
    pen.setWidth( 2 );

    // shrink the light on the LED to a size about 2/3 of the complete LED
    int pos = width/5 + 1;
    int light_width = width;
    light_width *= 2;
    light_width /= 3;
	
    // Calculate the LED´s "light factor":
    int light_quote = (130*2/(light_width?light_width:1))+100;

    // Now draw the bright spot on the LED:
    while (light_width) {
	color = color.light( light_quote );                      // make color lighter
	pen.setColor( color );                                   // set color as pen color
	paint.setPen( pen );                                     // select the pen for drawing
	paint.drawEllipse( pos, pos, light_width, light_width ); // draw the ellipse (circle)
	light_width--;
	if (!light_width)
	    break;
	paint.drawEllipse( pos, pos, light_width, light_width );
	light_width--;
	if (!light_width)
	    break;
	paint.drawEllipse( pos, pos, light_width, light_width );
	pos++; light_width--;
    }

    paint.drawPoint(pos, pos);

    // Drawing of bright spot finished, now draw a thin border
    // around the LED which resembles a shadow with light coming
    // from the upper left.

    pen.setWidth(2);
    brush.setStyle(Qt::NoBrush);
    paint.setBrush(brush); // This avoids filling of the ellipse

    // Set the initial color value to colorGroup().light() (bright) and start
    // drawing the shadow border at 45° (45*16 = 720).

    int angle = -720;
    color = palette().light().color();
    
    for (int arc = 120; arc < 2880; arc += 240) {
	pen.setColor(color);
	paint.setPen(pen);
	int w = width - pen.width()/2;
	paint.drawArc(pen.width()/2 + 1, pen.width()/2 + 1, w - 2, w - 2, angle + arc, 240);
	paint.drawArc(pen.width()/2 + 1, pen.width()/2 + 1, w - 2, w - 2, angle - arc, 240);
	color = color.dark(110); //FIXME: this should somehow use the contrast value
    }	// end for ( angle = 720; angle < 6480; angle += 160 )

    paint.end();
}

bool
LEDButton::state() const
{
    return led_state;
}

QColor
LEDButton::color() const
{
    return led_color;
}

void
LEDButton::setState( bool state )
{
    if (led_state != state)
    {
	led_state = state;
	update();
    }
}

void
LEDButton::toggleState()
{
    led_state = (led_state == true) ? false : true;
    // setColor(led_color);
    update();
}

void
LEDButton::setColor(const QColor& col)
{
    if(led_color!=col) {
	led_color = col;
	d->offcolor = col.dark(d->dark_factor);
	update();
    }
}

void
LEDButton::setDarkFactor(int darkfactor)
{
    if (d->dark_factor != darkfactor) {
	d->dark_factor = darkfactor;
	d->offcolor = led_color.dark(darkfactor);
	update();
    }
}

int
LEDButton::darkFactor() const
{
    return d->dark_factor;
}

void
LEDButton::toggle()
{
    toggleState();
}

void
LEDButton::on()
{
    setState(true);
}

void
LEDButton::off()
{
    setState(false);
}

QSize
LEDButton::sizeHint() const
{
    return QSize(17, 17);
}

QSize
LEDButton::minimumSizeHint() const
{
    return QSize(17, 17);
}