7 VUMeter *global_vu_meter = nullptr;
9 VUMeter::VUMeter(QWidget *parent)
14 void VUMeter::paintEvent(QPaintEvent *event)
16 QPainter painter(this);
18 painter.fillRect(0, 0, width(), height(), Qt::black);
22 unique_lock<mutex> lock(level_mutex);
26 const float min_level = 0.0f; // y=0 is top of screen, so “min” is the loudest level.
27 const float max_level = -60.0f;
28 int y = lrintf(height() * (level - min_level) / (max_level - min_level));
29 if (y >= 0 && y < height()) {
30 painter.setPen(Qt::white);
31 painter.drawLine(0, y, width(), y);