path: root/simple-visualization/qmppianowidget.cpp

#include <cstring>
#include <QPainter>
#include "qmppianowidget.hpp"

qmpPianoWidget::qmpPianoWidget(QWidget *parent) : QWidget(parent)
{
    memset(keystates, 0, sizeof(keystates));
    QPalette p = palette();
    p.setColor(QPalette::ColorRole::Highlight, 0xff66cc);
    p.setColor(QPalette::ColorRole::Base, 0x66ccff);
    setPalette(p);
}
void qmpPianoWidget::setKeyState(int key, bool state)
{
    keystates[key] = state;
    update();
}
void qmpPianoWidget::reset()
{
    memset(keystates, 0, sizeof(keystates));
    update();
}
QSize qmpPianoWidget::minimumSizeHint()const
{
    return QSize(320, 22);
}

bool qmpPianoWidget::hasHeightForWidth()const
{
    return true;
}

int qmpPianoWidget::heightForWidth(int w)const
{
    return w * 22 / 320;
}

void qmpPianoWidget::paintEvent(QPaintEvent *event)
{
    Q_UNUSED(event)
    for (int i = 0; i < 128; ++i)
    {
        QRectF r = getKeyRect(i);
        QColor activeColor = palette().color(QPalette::ColorRole::Highlight);
        QColor inactiveColor = palette().color(QPalette::ColorRole::Base);
        if (i / 12 % 2)
        {
            if (inactiveColor.valueF() > 0.5)
                inactiveColor = inactiveColor.darker(112);
            else
                inactiveColor = inactiveColor.lighter(112);
        }
        paintKey(r, keystates[i] ? activeColor : inactiveColor);
    }
}

QRectF qmpPianoWidget::getKeyRect(int key)
{
    int octave = key / 12;
    key %= 12;
    bool is_black = (key < 5 && (key & 1)) || (key > 5 && ((key & 1) ^ 1));
    double key_width = width() / 75.;
    QRectF ret(0, 0, key_width, height() / 2.);
    if (!is_black)
    {
        ret.moveTop(height() / 2.);
        int shift = (key + (key >= 5)) >> 1;
        ret.moveLeft((octave * 7 + shift)*key_width);
    }
    else
        ret.moveLeft((octave * 7 + (key + (key >= 5)) / 2.)*key_width);
    return ret;
}
void qmpPianoWidget::paintKey(QRectF keyrect, QColor keycolor)
{
    QColor bordercolor(keycolor);
    if (keycolor.valueF() > 0.5)
        bordercolor = bordercolor.darker(150);
    else
        bordercolor = bordercolor.lighter(150);
    QPainter *p = new QPainter(this);
    p->setPen(bordercolor);
    p->setBrush(QBrush(keycolor));
    p->drawRect(keyrect.adjusted(1, 1, -1, -1));
    delete p;
}