waveformview: implemented basic waveformview display

app/widget/timelinewidget/timelinescaledobject.h

@@ -45,6 +45,7 @@ private:
 
 class TimelineScaledWidget : public QWidget, public TimelineScaledObject
 {
+  Q_OBJECT
 public:
   TimelineScaledWidget(QWidget* parent = nullptr);
 };

app/widget/timelinewidget/view/timelineviewblockitem.cpp

@@ -29,11 +29,10 @@
 #include <QPainter>
 #include <QStyleOptionGraphicsItem>
 
-#include "audio/sumsamples.h"
-#include "common/clamp.h"
 #include "common/qtutils.h"
 #include "config/config.h"
 #include "node/block/transition/transition.h"
+#include "widget/viewer/waveformview.h"
 
 TimelineViewBlockItem::TimelineViewBlockItem(Block *block, QGraphicsItem* parent) :
   TimelineViewRect(parent),
@@ -94,47 +93,12 @@ void TimelineViewBlockItem::paint(QPainter *painter, const QStyleOptionGraphicsI
       QByteArray w = wave_file.readAll();
 
       // FIXME: Hardcoded channel count
-      int channels = 2;
+      WaveformView::DrawWaveform(painter,
-
+                                 rect().toRect(),
-      const SampleSummer::Sum* samples = reinterpret_cast<const SampleSummer::Sum*>(w.constData());
+                                 this->GetScale(),
-      int nb_samples = w.size() / sizeof(SampleSummer::Sum);
+                                 reinterpret_cast<const SampleSummer::Sum*>(w.constData()),
-
+                                 w.size() / sizeof(SampleSummer::Sum),
-      int sample_index, next_sample_index = 0;
+                                 2);
-
-      QVector<SampleSummer::Sum> summary;
-      int summary_index = -1;
-
-      int channel_height = rect().height() / channels;
-      int channel_half_height = channel_height / 2;
-
-      for (int i=0;i<rect().width();i++) {
-        sample_index = next_sample_index;
-
-        if (sample_index == nb_samples) {
-          break;
-        }
-
-        next_sample_index = qMin(nb_samples,
-                                 qFloor(static_cast<double>(SampleSummer::kSumSampleRate) * static_cast<double>(i+1) / this->GetScale()) * channels);
-
-        if (summary_index != sample_index) {
-          summary = SampleSummer::ReSumSamples(&samples[sample_index],
-                                               qMax(channels, next_sample_index - sample_index),
-                                               channels);
-          summary_index = sample_index;
-        }
-
-        int line_x = i + rect().x();
-
-        for (int j=0;j<summary.size();j++) {
-          int channel_mid = rect().y() + channel_height * j + channel_half_height;
-
-          painter->drawLine(line_x,
-                            channel_mid + clamp(qRound(summary.at(j).min * channel_half_height), -channel_half_height, channel_half_height),
-                            line_x,
-                            channel_mid + clamp(qRound(summary.at(j).max * channel_half_height), -channel_half_height, channel_half_height));
-        }
-      }
 
       wave_file.close();
     }

app/widget/viewer/viewer.cpp

@@ -70,6 +70,7 @@ ViewerWidget::ViewerWidget(QWidget *parent) :
   // Create scrollbar
   layout->addWidget(scrollbar());
   connect(scrollbar(), &QScrollBar::valueChanged, ruler(), &TimeRuler::SetScroll);
+  connect(scrollbar(), &QScrollBar::valueChanged, waveform_view_, &WaveformView::SetScroll);
 
   // Create lower controls
   controls_ = new PlaybackControls();
@@ -94,6 +95,8 @@ ViewerWidget::ViewerWidget(QWidget *parent) :
   connect(video_renderer_, &VideoRenderBackend::RangeInvalidated, ruler(), &TimeRuler::CacheInvalidatedRange);
   audio_renderer_ = new AudioBackend(this);
 
+  waveform_view_->SetBackend(audio_renderer_);
+
   connect(PixelFormat::instance(), &PixelFormat::FormatChanged, this, &ViewerWidget::UpdateRendererParameters);
 
   SetAutoMaxScrollBar(true);
@@ -180,6 +183,13 @@ void ViewerWidget::ConnectedNodeChanged(ViewerOutput *n)
   audio_renderer_->SetViewerNode(n);
 }
 
+void ViewerWidget::ScaleChangedEvent(const double &s)
+{
+  TimeBasedWidget::ScaleChangedEvent(s);
+
+  waveform_view_->SetScale(s);
+}
+
 void ViewerWidget::resizeEvent(QResizeEvent *event)
 {
   TimeBasedWidget::resizeEvent(event);

app/widget/viewer/viewer.h

@@ -114,6 +114,8 @@ protected:
   virtual void DisconnectNodeInternal(ViewerOutput *) override;
   virtual void ConnectedNodeChanged(ViewerOutput*n) override;
 
+  virtual void ScaleChangedEvent(const double& s) override;
+
   virtual void resizeEvent(QResizeEvent *event) override;
 
   OpenGLBackend* video_renderer_;

app/widget/viewer/waveformview.cpp

@@ -1,24 +1,148 @@
 #include "waveformview.h"
 
+#include <QFile>
 #include <QPainter>
 #include <QtMath>
 
+#include "common/clamp.h"
+
 WaveformView::WaveformView(QWidget *parent) :
-  TimeBasedWidget(parent)
+  TimelineScaledWidget(parent),
+  backend_(nullptr)
 {
   setAutoFillBackground(true);
-  setStyleSheet("background: black;");
+  setBackgroundRole(QPalette::Base);
+}
+
+void WaveformView::SetBackend(AudioRenderBackend *backend)
+{
+  if (backend_) {
+    disconnect(backend_, &AudioRenderBackend::QueueComplete, this, static_cast<void (WaveformView::*)()>(&WaveformView::update));
+  }
+
+  backend_ = backend;
+
+  if (backend_) {
+    connect(backend_, &AudioRenderBackend::QueueComplete, this, static_cast<void (WaveformView::*)()>(&WaveformView::update));
+  }
+
+  update();
+}
+
+void WaveformView::DrawWaveform(QPainter *painter, const QRect& rect, const double& scale, const SampleSummer::Sum* samples, int nb_samples, int channels)
+{
+  int sample_index, next_sample_index = 0;
+
+  QVector<SampleSummer::Sum> summary;
+  int summary_index = -1;
+
+  int channel_height = rect.height() / channels;
+  int channel_half_height = channel_height / 2;
+
+  for (int i=0;i<rect.width();i++) {
+    sample_index = next_sample_index;
+
+    if (sample_index == nb_samples) {
+      break;
+    }
+
+    next_sample_index = qMin(nb_samples,
+                             qFloor(static_cast<double>(SampleSummer::kSumSampleRate) * static_cast<double>(i+1) / scale) * channels);
+
+    if (summary_index != sample_index) {
+      summary = SampleSummer::ReSumSamples(&samples[sample_index],
+                                           qMax(channels, next_sample_index - sample_index),
+                                           channels);
+      summary_index = sample_index;
+    }
+
+    int line_x = i + rect.x();
+
+    for (int j=0;j<summary.size();j++) {
+      int channel_mid = rect.y() + channel_height * j + channel_half_height;
+
+      painter->drawLine(line_x,
+                        channel_mid + clamp(qRound(summary.at(j).min * channel_half_height), -channel_half_height, channel_half_height),
+                        line_x,
+                        channel_mid + clamp(qRound(summary.at(j).max * channel_half_height), -channel_half_height, channel_half_height));
+    }
+  }
+}
+
+void WaveformView::SetScroll(int scroll)
+{
+  scroll_ = scroll;
+
+  qDebug() << "Got scroll" << scroll_;
+
+  update();
 }
 
 void WaveformView::paintEvent(QPaintEvent *event)
 {
   QWidget::paintEvent(event);
 
-  QPainter p(this);
+  if (!backend_ || backend_->CachePathName().isEmpty() || !backend_->params().is_valid()) {
+    return;
+  }
 
-  p.setPen(Qt::green);
+  const AudioRenderingParams& params = backend_->params();
+
+  QFile fs(backend_->CachePathName());
+
+  if (fs.open(QFile::ReadOnly)) {
+
+    QPainter p(this);
+
+    p.setPen(Qt::green);
+
+    int channel_height = height() / params.channel_count();
+    int channel_half_height = channel_height / 2;
+
+    int drew = 0;
+
+    fs.seek(params.samples_to_bytes(GetSampleIndexFromPixel(0)));
+
+    for (int x=0; x<width() && !fs.atEnd(); x++) {
+
+      int samples_len = GetSampleIndexFromPixel(x+1) - GetSampleIndexFromPixel(x);
+      int max_read_size = params.samples_to_bytes(samples_len);
+
+      QByteArray read_buffer = fs.read(max_read_size);
+
+      // Detect whether we've reached EOF and recalculate sample count if so
+      if (read_buffer.size() < max_read_size) {
+        samples_len = params.bytes_to_samples(read_buffer.size());
+      }
+
+      QVector<SampleSummer::Sum> samples = SampleSummer::SumSamples(reinterpret_cast<const float*>(read_buffer.constData()),
+                                                                    samples_len,
+                                                                    params.channel_count());
+
+      for (int i=0;i<params.channel_count();i++) {
+        int channel_mid = channel_height * i + channel_half_height;
+
+        p.drawLine(x,
+                   channel_mid + samples.at(i).min * static_cast<float>(channel_half_height),
+                   x,
+                   channel_mid + samples.at(i).max * static_cast<float>(channel_half_height));
+
+        drew++;
+      }
+    }
+
+    fs.close();
 
-  for (int i=0;i<width();i++) {
-    p.drawPoint(i, (height() / 2) + qSin(static_cast<double>(i) * 0.025) * (height() / 2));
   }
 }
+
+void WaveformView::ScaleChangedEvent(const double &)
+{
+  update();
+}
+
+int WaveformView::GetSampleIndexFromPixel(int x) const
+{
+  qDebug() << "X was" << x << "scroll was" << scroll_ << "=" << (x + scroll_);
+  return qRound(static_cast<double>(x + scroll_) * static_cast<double>(backend_->params().sample_rate()) / GetScale());
+}

app/widget/viewer/waveformview.h

@@ -1,16 +1,40 @@
 #ifndef WAVEFORMVIEW_H
 #define WAVEFORMVIEW_H
 
-#include "widget/timebased/timebased.h"
+#include <QWidget>
 
-class WaveformView : public TimeBasedWidget
+#include "audio/sumsamples.h"
+#include "render/audioparams.h"
+#include "render/backend/audiorenderbackend.h"
+#include "widget/timelinewidget/timelinescaledobject.h"
+
+class WaveformView : public TimelineScaledWidget
 {
+  Q_OBJECT
 public:
   WaveformView(QWidget* parent = nullptr);
 
+  //void SetData(const QString& file, const AudioRenderingParams& params);
+
+  void SetBackend(AudioRenderBackend* backend);
+
+  static void DrawWaveform(QPainter* painter, const QRect &rect, const double &scale, const SampleSummer::Sum *samples, int nb_samples, int channels);
+
+public slots:
+  void SetScroll(int scroll);
+
 protected:
   virtual void paintEvent(QPaintEvent* event) override;
 
+  virtual void ScaleChangedEvent(const double& s) override;
+
+private:
+  int GetSampleIndexFromPixel(int x) const;
+
+  AudioRenderBackend* backend_;
+
+  int scroll_;
+
 };
 
 #endif // WAVEFORMVIEW_H