view widgets/IconLoader.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 file copyright 2007 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 "IconLoader.h"

#include <QPixmap>
#include <QApplication>
#include <QPainter>
#include <QPalette>

static const char *autoInvertExceptions[] = {
    // These are the icons that look OK in their default colours, even
    // in a colour scheme with a black background.  (They may also be
    // icons that would look worse if we tried to auto-invert them.)
    // If we have icons that look bad when auto-inverted but that are
    // not suitable for use without being inverted, we'll need to
    // supply inverted versions -- the loader will load xx_inverse.png
    // in preference to xx.png if a dark background is found.)
    "fileclose",
    "filenew-22",
    "filenew",
    "fileopen-22",
    "fileopen",
    "fileopenaudio",
    "fileopensession",
    "filesave-22",
    "filesave",
    "filesaveas-22",
    "filesaveas",
    "help",
    "editcut",
    "editcopy",
    "editpaste",
    "editdelete",
    "exit",
    "zoom-fit",
    "zoom-in",
    "zoom-out",
    "zoom"
};

QIcon
IconLoader::load(QString name)
{
    QPixmap pmap(loadPixmap(name));
    if (pmap.isNull()) return QIcon();
    else return QIcon(pmap);
}

QPixmap
IconLoader::loadPixmap(QString name)
{
    QColor bg = QApplication::palette().window().color();
    if (bg.red() + bg.green() + bg.blue() > 384) { // light background
        QPixmap pmap(QString(":icons/%1").arg(name));
        if (pmap.isNull()) {
            pmap = QPixmap(QString(":icons/%1.png").arg(name));
        }
        return pmap;
    }

    QPixmap pmap(QString(":icons/%1").arg(name));
    if (pmap.isNull()) {
        pmap = QPixmap(QString(":icons/%1_inverse.png").arg(name));
        if (pmap.isNull()) {
            pmap = QPixmap(QString(":icons/%1.png").arg(name));
        }
    }
    if (pmap.isNull()) return pmap;

    for (int i = 0; i < sizeof(autoInvertExceptions)/
                        sizeof(autoInvertExceptions[0]); ++i) {
        if (autoInvertExceptions[i] == name) {
            return pmap;
        }
    }

    // No suitable inverted icon found for black background; try to
    // auto-invert the default one

    QImage img = pmap.toImage().convertToFormat(QImage::Format_ARGB32);

    for (int y = 0; y < img.height(); ++y) {
        for (int x = 0; x < img.width(); ++x) {

            QRgb rgba = img.pixel(x, y);
            QColor colour = QColor
                (qRed(rgba), qGreen(rgba), qBlue(rgba), qAlpha(rgba));

            int alpha = colour.alpha();
            if (colour.saturation() < 5 && colour.alpha() > 10) {
                colour.setHsv(colour.hue(),
                              colour.saturation(),
                              255 - colour.value());
                colour.setAlpha(alpha);
                img.setPixel(x, y, colour.rgba());
            }
        }
    }

    pmap = QPixmap::fromImage(img);
    return pmap;
}