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

   1 #include "correlation_meter.h"
   2
   3 #include <math.h>
   4 #include <algorithm>
   5 #include <mutex>
   6
   7 #include <QBrush>
   8 #include <QColor>
   9 #include <QPaintDevice>
  10 #include <QPainter>
  11 #include <QPixmap>
  12 #include <QRect>
  13 #include <QWidget>
  14
  15 class QPaintEvent;
  16 class QResizeEvent;
  17
  18 using namespace std;
  19
  20 CorrelationMeter::CorrelationMeter(QWidget *parent)
  21         : QWidget(parent)
  22 {
  23 }
  24
  25 void CorrelationMeter::resizeEvent(QResizeEvent *event)
  26 {
  27         on_pixmap = QPixmap(width(), height());
  28         QPainter on_painter(&on_pixmap);
  29         QLinearGradient on(0, 0, width(), 0);
  30         on.setColorAt(0.0f, QColor(255, 0, 0));
  31         on.setColorAt(0.5f, QColor(255, 255, 0));
  32         on.setColorAt(0.8f, QColor(0, 255, 0));
  33         on.setColorAt(0.95f, QColor(255, 255, 0));
  34         on_painter.fillRect(0, 0, width(), height(), Qt::black);
  35         on_painter.fillRect(1, 1, width() - 2, height() - 2, on);
  36
  37         off_pixmap = QPixmap(width(), height());
  38         QPainter off_painter(&off_pixmap);
  39         QLinearGradient off(0, 0, width(), 0);
  40         off.setColorAt(0.0f, QColor(127, 0, 0));
  41         off.setColorAt(0.5f, QColor(127, 127, 0));
  42         off.setColorAt(0.8f, QColor(0, 127, 0));
  43         off.setColorAt(0.95f, QColor(127, 127, 0));
  44         off_painter.fillRect(0, 0, width(), height(), Qt::black);
  45         off_painter.fillRect(1, 1, width() - 2, height() - 2, off);
  46 }
  47
  48 void CorrelationMeter::paintEvent(QPaintEvent *event)
  49 {
  50         QPainter painter(this);
  51
  52         float correlation;
  53         {
  54                 lock_guard<mutex> lock(correlation_mutex);
  55                 correlation = this->correlation;
  56         }
  57
  58         // Just in case.
  59         correlation = std::min(std::max(correlation, -1.0f), 1.0f);
  60
  61         int pos = 3 + lrintf(0.5f * (correlation + 1.0f) * (width() - 6));
  62         QRect off_rect(0, 0, width(), height());
  63         QRect on_rect(pos - 2, 0, 5, height());
  64
  65         painter.drawPixmap(off_rect, off_pixmap, off_rect);
  66         painter.drawPixmap(on_rect, on_pixmap, on_rect);
  67 }