git.sesse.net Git - nageru/blob - compression_reduction_meter.cpp

   1 #include "compression_reduction_meter.h"
   2
   3 #include <QPainter>
   4 #include <QRect>
   5 #include "piecewise_interpolator.h"
   6 #include "vu_common.h"
   7
   8 class QPaintEvent;
   9 class QResizeEvent;
  10
  11 using namespace std;
  12
  13 namespace {
  14
  15 vector<PiecewiseInterpolator::ControlPoint> control_points = {
  16         { 60.0f, 6.0f },
  17         { 30.0f, 5.0f },
  18         { 18.0f, 4.0f },
  19         { 12.0f, 3.0f },
  20         { 6.0f, 2.0f },
  21         { 3.0f, 1.0f },
  22         { 0.0f, 0.0f }
  23 };
  24 PiecewiseInterpolator interpolator(control_points);
  25
  26 }  // namespace
  27
  28 CompressionReductionMeter::CompressionReductionMeter(QWidget *parent)
  29         : QWidget(parent)
  30 {
  31 }
  32
  33 void CompressionReductionMeter::resizeEvent(QResizeEvent *event)
  34 {
  35         recalculate_pixmaps();
  36 }
  37
  38 void CompressionReductionMeter::paintEvent(QPaintEvent *event)
  39 {
  40         QPainter painter(this);
  41
  42         float level_db;
  43         {
  44                 unique_lock<mutex> lock(level_mutex);
  45                 level_db = this->level_db;
  46         }
  47
  48         int on_pos = lrint(db_to_pos(level_db));
  49
  50         QRect on_rect(0, 0, width(), on_pos);
  51         QRect off_rect(0, on_pos, width(), height());
  52
  53         painter.drawPixmap(on_rect, on_pixmap, on_rect);
  54         painter.drawPixmap(off_rect, off_pixmap, off_rect);
  55 }
  56
  57 void CompressionReductionMeter::recalculate_pixmaps()
  58 {
  59         constexpr int y_offset = text_box_height / 2;
  60         constexpr int text_margin = 5;
  61         float margin = 0.5 * (width() - meter_width);
  62
  63         on_pixmap = QPixmap(width(), height());
  64         QPainter on_painter(&on_pixmap);
  65         on_painter.fillRect(0, 0, width(), height(), parentWidget()->palette().window());
  66         draw_vu_meter(on_painter, width(), meter_height(), margin, 2.0, true, min_level, max_level, /*flip=*/true, y_offset);
  67         draw_scale(&on_painter, 0.5 * width() + 0.5 * meter_width + text_margin);
  68
  69         off_pixmap = QPixmap(width(), height());
  70         QPainter off_painter(&off_pixmap);
  71         off_painter.fillRect(0, 0, width(), height(), parentWidget()->palette().window());
  72         draw_vu_meter(off_painter, width(), meter_height(), margin, 2.0, false, min_level, max_level, /*flip=*/true, y_offset);
  73         draw_scale(&off_painter, 0.5 * width() + 0.5 * meter_width + text_margin);
  74 }
  75
  76 void CompressionReductionMeter::draw_scale(QPainter *painter, int x_pos)
  77 {
  78         QFont font;
  79         font.setPointSize(8);
  80         painter->setPen(Qt::black);
  81         painter->setFont(font);
  82         for (size_t i = 0; i < control_points.size(); ++i) {
  83                 char buf[256];
  84                 snprintf(buf, 256, "%.0f", control_points[i].db_value);
  85                 double y = db_to_pos(control_points[i].db_value);
  86                 painter->drawText(QRect(x_pos, y - text_box_height / 2, text_box_width, text_box_height),
  87                         Qt::AlignCenter | Qt::AlignVCenter, buf);
  88         }
  89 }
  90
  91 double CompressionReductionMeter::db_to_pos(double level_db) const
  92 {
  93         float value = interpolator.db_to_fraction(level_db);
  94         return height() - lufs_to_pos(value, meter_height(), min_level, max_level) - text_box_height / 2;
  95 }
  96
  97 int CompressionReductionMeter::meter_height() const
  98 {
  99         return height() - text_box_height;
 100 }