Added cursor on time ruler and ability to play from cursor

Author: BenPyton

Signal.cpp

@@ -39,6 +39,7 @@ Signal::Signal(QObject *_parent)
 
     int totalSample = 1 * m_sampleRate;
     m_samples = new QByteArray(totalSample, NULL);
+    m_cursorSample = 0;
 
     QAudioFormat format;
     // Set up the format, eg.
@@ -131,6 +132,11 @@ qint32 Signal::getSample(int _index)
     return 0;
 }
 
+void Signal::setCursorTime(qreal _cursorTime)
+{
+    m_cursorSample = qRound(_cursorTime * m_sampleRate);
+}
+
 void Signal::generate()
 {
     int totalSample = qRound(m_duration * m_sampleRate);
@@ -205,6 +211,7 @@ void Signal::pause()
 void Signal::toStart()
 {
     m_buffer->reset();
+    m_buffer->seek(m_cursorSample * 4);
 }
 
 void Signal::toEnd()

Signal.h

@@ -48,6 +48,8 @@ class Signal : public QObject
     int sampleCount();
     qint32 getSample(int _index);
     inline int getSampleRate() { return m_sampleRate; }
+    inline int getCursorSample() { return m_cursorSample; }
+    inline void setCursorSample(int _cursorSample) { m_cursorSample = _cursorSample; }
 
 signals:
     void signalChanged();
@@ -62,6 +64,7 @@ public slots:
     void generate();
     void exportWAV(QString _fileName);
     void loop(bool _enable);
+    void setCursorTime(qreal _cursorTime);
 
 private slots:
     void handleStateChanged(QAudio::State _newState);
@@ -73,6 +76,7 @@ private slots:
     QByteArray* m_samples;
     LoopableBuffer* m_buffer;
     Component* m_component;
+    int m_cursorSample;
 };
 
 

UI/MainWindow.cpp

@@ -60,6 +60,8 @@ MainWindow::MainWindow(QWidget* _parent)
     ui->waveFormView->setSignal(&m_signal);
     connect(ui->waveFormView, &WaveFormView::zoomChanged, this, &MainWindow::onWaveFormViewZoomChanged);
     connect(ui->waveFormScrollBar, &QScrollBar::valueChanged, this, &MainWindow::onScrollbarValueChanged);
+    connect(ui->timeRuler, &TimeRuler::onTimeSelected, ui->waveFormView, &WaveFormView::setCursorTime);
+    connect(ui->timeRuler, &TimeRuler::onTimeSelected, &m_signal, &Signal::setCursorTime);
 
     m_scene = new NodalScene(ui->nodalView);
     m_scene->setBackgroundBrush(Qt::black);

UI/TimeRuler.cpp

@@ -27,8 +27,6 @@
 TimeRuler::TimeRuler(QWidget *_parent)
     : QWidget(_parent)
 {
-    m_startTime = 0.0;
-    m_endTime = 1.0;
 }
 
 void TimeRuler::setTimeWindow(qreal _startTime, qreal _endTime)
@@ -87,4 +85,62 @@ void TimeRuler::paintEvent(QPaintEvent *_event)
     }
 
     painter.drawLines(lines);
+
+    QBrush brush(Qt::BrushStyle::SolidPattern);
+    brush.setColor(QColor(255, 255, 0));
+    painter.setRenderHint(QPainter::Antialiasing);
+    painter.setPen(Qt::NoPen);
+
+    int cursorRadius = 2;
+    int height = size().height() - 1;
+    int x = qRound(Utils::MapValue(m_currentTime, m_startTime, m_endTime, 0.0, size().width())) - CURSOR_HALF_WIDTH;
+
+    QPainterPath cursor;
+    cursor.moveTo(x, cursorRadius);
+    cursor.arcTo(x, 0, 2 * cursorRadius, 2 * cursorRadius, 180, -90);
+    cursor.arcTo(x + CURSOR_HALF_WIDTH * 2 - 2 * cursorRadius, 0, 2 * cursorRadius, 2 * cursorRadius, 90, -90);
+    cursor.lineTo(x + 2 * CURSOR_HALF_WIDTH, height - CURSOR_HALF_WIDTH);
+    cursor.lineTo(x + CURSOR_HALF_WIDTH, height);
+    cursor.lineTo(x, height - CURSOR_HALF_WIDTH);
+    cursor.closeSubpath();
+
+    painter.fillPath(cursor, brush);
+}
+
+void TimeRuler::mousePressEvent(QMouseEvent *_event)
+{
+    if(_event->button() == Qt::MouseButton::LeftButton)
+    {
+        m_draggingCursor = true;
+        int cursorPos = qRound(Utils::MapValue(m_currentTime, m_startTime, m_endTime, 0.0, size().width()));
+        int mousePos = _event->pos().x();
+        m_cursorOffset = qAbs(cursorPos - mousePos) < CURSOR_HALF_WIDTH ? cursorPos - mousePos : 0;
+        updateCursor(mousePos);
+    }
+}
+
+void TimeRuler::mouseMoveEvent(QMouseEvent *_event)
+{
+    if(m_draggingCursor)
+    {
+        updateCursor(_event->pos().x());
+    }
+}
+
+void TimeRuler::mouseReleaseEvent(QMouseEvent *_event)
+{
+    Q_UNUSED(_event)
+
+    if(_event->button() == Qt::MouseButton::LeftButton)
+    {
+        m_draggingCursor = false;
+    }
+}
+
+void TimeRuler::updateCursor(int _mousePosX)
+{
+    qreal value = static_cast<qreal>(_mousePosX + m_cursorOffset);
+    m_currentTime = Utils::MapValue(value, 0, static_cast<qreal>(size().width()), m_startTime, m_endTime);
+    update();
+    emit onTimeSelected(m_currentTime);
 }

UI/TimeRuler.h

@@ -21,7 +21,7 @@
 #ifndef TIMERULER_H
 #define TIMERULER_H
 
-#include <QWidget>
+#include <QtWidgets>
 
 class TimeRuler : public QWidget
 {
@@ -33,16 +33,28 @@ class TimeRuler : public QWidget
     void setTimeWindow(qreal _startTime, qreal _endTime);
     inline qreal getStartTime() { return m_startTime; }
     inline qreal getEndTime() { return m_endTime; }
+    inline qreal getCurrentTime() { return m_currentTime; }
 
 public slots:
     virtual void paintEvent(QPaintEvent* _event) override;
+    virtual void mousePressEvent(QMouseEvent* _event) override;
+    virtual void mouseMoveEvent(QMouseEvent* _event) override;
+    virtual void mouseReleaseEvent(QMouseEvent* _event) override;
 
 signals:
     void onTimeSelected(qreal _time);
 
+private:
+    void updateCursor(int mousePosX);
+
 private:
     qreal m_startTime = 0.0;
     qreal m_endTime = 0.0;
+    qreal m_currentTime = 0.0;
+    bool m_draggingCursor = false;
+    int m_cursorOffset = 0.0;
+
+    static const int CURSOR_HALF_WIDTH = 4;
 };
 
 #endif // TIMERULER_H

UI/WaveFormView.cpp

@@ -21,6 +21,7 @@
 #include "WaveFormView.h"
 #include "WaveFormChunk.h"
 #include <QPainter>
+#include "Utils.h"
 
 const int WaveFormView::chunkSize = 128;
 
@@ -30,6 +31,7 @@ WaveFormView::WaveFormView(QWidget *_parent)
     m_sampleOffset = 0;
     m_nbSampleViewed = 2400;
     m_nbTotalSample = 0;
+    m_cursorSample = 0;
 
     m_samplePerChunk = chunkSize;
 
@@ -61,6 +63,12 @@ void WaveFormView::setSignal(Signal *_signal)
     }
 }
 
+void WaveFormView::setCursorTime(qreal cursorTime)
+{
+    m_cursorSample = qRound(m_signal->getSampleRate() * cursorTime);
+    update();
+}
+
 void WaveFormView::resizeEvent(QResizeEvent *_event)
 {
     Q_UNUSED(_event);
@@ -102,6 +110,12 @@ void WaveFormView::paintEvent(QPaintEvent *_event)
                            m_chunkList[i]->width(), m_chunkList[i]->height());
     }
 
+    int x = qRound(Utils::MapValue(m_cursorSample - m_sampleOffset, 0, m_nbSampleViewed, 0, size().width()));
+
+    QPen pen(QColor("yellow"));
+    painter.setPen(pen);
+    painter.drawLine(x, 0, x, size().width());
+
 }
 
 void WaveFormView::wheelEvent(QWheelEvent *_event)

UI/WaveFormView.h

@@ -36,6 +36,7 @@ class WaveFormView : public QWidget
     virtual ~WaveFormView() override;
 
     void setSignal(Signal* _signal);
+    void setCursorTime(qreal cursorTime);
 
     inline int getSampleOffset() { return m_sampleOffset; }
     inline int getNbSampleViewed() { return m_nbSampleViewed; }
@@ -61,6 +62,7 @@ public slots:
     int m_nbSampleViewed;
     int m_nbTotalSample;
     int m_samplePerChunk;
+    int m_cursorSample;
 
     qreal m_zoom;
     qreal m_zoomMin;