view widgets/IconLoader.cpp @ 1509:8145a9c4c253

The default key frame map is not working well at the moment, because its extents are not being properly updated as the models they depend on are loaded. Leave it empty for now.

/* -*- 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>
#include <QFile>
#include <QSvgRenderer>
#include <QSettings>

#include <vector>
#include <set>

#include "base/Debug.h"

using namespace std;

static set<QString> 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",
    "fileopen",
    "fileopenaudio",
    "fileopensession",
    "filesave",
    "filesaveas",
    "filesaveas-sv",
    "help",
    "editcut",
    "editcopy",
    "editpaste",
    "editdelete",
    "exit",
    "zoom-fit",
    "zoom-in",
    "zoom-out",
    "zoom"
};

static vector<int> sizes { 0, 16, 22, 24, 32, 48, 64, 128 };

QIcon
IconLoader::load(QString name)
{
    QIcon icon;
    for (int sz: sizes) {
        QPixmap pmap(loadPixmap(name, sz));
        if (!pmap.isNull()) icon.addPixmap(pmap);
    }
    return icon;
}

bool
IconLoader::shouldInvert() const
{
    QSettings settings;
    settings.beginGroup("IconLoader");
    if (!settings.value("invert-icons-on-dark-background", true).toBool()) {
        return false;
    }
    QColor bg = QApplication::palette().window().color();
    bool darkBackground = (bg.red() + bg.green() + bg.blue() <= 384);
    return darkBackground;
}

bool
IconLoader::shouldAutoInvert(QString name) const
{
    if (shouldInvert()) {
        return (autoInvertExceptions.find(name) == autoInvertExceptions.end());
    } else {
        return false;
    }
}

QPixmap
IconLoader::loadPixmap(QString name, int size)
{
    bool invert = shouldInvert();

    QString scalableName, nonScalableName;
    QPixmap pmap;

    // attempt to load a pixmap with the right size and inversion
    nonScalableName = makeNonScalableFilename(name, size, invert);
    pmap = QPixmap(nonScalableName);

    if (pmap.isNull() && size > 0) {
        // if that failed, load a scalable vector with the right
        // inversion and scale it
        scalableName = makeScalableFilename(name, invert);
        pmap = loadScalable(scalableName, size);
    }

    if (pmap.isNull() && invert) {
        // if that failed, and we were asking for an inverted pixmap,
        // that may mean we don't have an inverted version of it. We
        // could either auto-invert or use the uninverted version
        nonScalableName = makeNonScalableFilename(name, size, false);
        pmap = QPixmap(nonScalableName);

        if (pmap.isNull() && size > 0) {
            scalableName = makeScalableFilename(name, false);
            pmap = loadScalable(scalableName, size);
        }
        
        if (!pmap.isNull() && shouldAutoInvert(name)) {
            pmap = invertPixmap(pmap);
        }
    }

    return pmap;
}

QPixmap
IconLoader::loadScalable(QString name, int size)
{
    if (!QFile(name).exists()) {
//        cerr << "loadScalable: no such file as: \"" << name << "\"" << endl;
        return QPixmap();
    }
    QPixmap pmap(size, size);
    pmap.fill(Qt::transparent);
    QSvgRenderer renderer(name);
    QPainter painter;
    painter.begin(&pmap);
//    cerr << "calling renderer for " << name << " at size " << size << "..." << endl;
    renderer.render(&painter);
//    cerr << "renderer completed" << endl;
    painter.end();
    return pmap;
}

QString
IconLoader::makeNonScalableFilename(QString name, int size, bool invert)
{
    if (invert) {
        if (size == 0) {
            return QString(":icons/%1_inverse.png").arg(name);
        } else {
            return QString(":icons/%1-%2_inverse.png").arg(name).arg(size);
        }
    } else {
        if (size == 0) {
            return QString(":icons/%1.png").arg(name);
        } else {
            return QString(":icons/%1-%2.png").arg(name).arg(size);
        }
    }
}

QString
IconLoader::makeScalableFilename(QString name, bool invert)
{
    if (invert) {
        return QString(":icons/scalable/%1_inverse.svg").arg(name);
    } else {
        return QString(":icons/scalable/%1.svg").arg(name);
    }
}

QPixmap
IconLoader::invertPixmap(QPixmap 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;
}