WaveRubber: a simple waveform analyzer

This kinda elastic analyzer uses no transformations and is colored by a gradient based on the user QT "Highlight" palette.

WaveRubber: a kinda elastic waveform analyzer

Update src/analyzer/waverubber.cpp

better pointer declaration

Co-authored-by: Jonas Kvinge <jonas@jkvinge.net>

src/CMakeLists.txt

@@ -74,6 +74,7 @@ set(SOURCES
   analyzer/boomanalyzer.cpp
   analyzer/rainbowanalyzer.cpp
   analyzer/sonogram.cpp
+  analyzer/waverubber.cpp
 
   equalizer/equalizer.cpp
   equalizer/equalizerslider.cpp
@@ -331,6 +332,7 @@ set(HEADERS
   analyzer/boomanalyzer.h
   analyzer/rainbowanalyzer.h
   analyzer/sonogram.h
+  analyzer/waverubber.h
 
   equalizer/equalizer.h
   equalizer/equalizerslider.h

src/analyzer/analyzercontainer.cpp

@@ -41,6 +41,7 @@
 #include "boomanalyzer.h"
 #include "rainbowanalyzer.h"
 #include "sonogram.h"
+#include "waverubber.h"
 
 #include "core/logging.h"
 #include "core/shared_ptr.h"
@@ -88,6 +89,7 @@ AnalyzerContainer::AnalyzerContainer(QWidget *parent)
   AddAnalyzerType<NyanCatAnalyzer>();
   AddAnalyzerType<RainbowDashAnalyzer>();
   AddAnalyzerType<Sonogram>();
+  AddAnalyzerType<WaveRubber>();
 
   disable_action_ = context_menu_->addAction(tr("No analyzer"), this, &AnalyzerContainer::DisableAnalyzer);
   disable_action_->setCheckable(true);

src/analyzer/waverubber.cpp

@@ -0,0 +1,93 @@
+/*
+   Strawberry Music Player
+   Copyright 2024, Gustavo L Conte <suporte@gu.pro.br>
+
+   Strawberry is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   Strawberry is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <QPainter>
+#include <QResizeEvent>
+#include "engine/enginebase.h"
+#include "waverubber.h"
+
+const char *WaveRubber::kName = QT_TRANSLATE_NOOP("AnalyzerContainer", "WaveRubber");
+
+WaveRubber::WaveRubber(QWidget *parent)
+  : AnalyzerBase(parent, 9) {}
+
+void WaveRubber::resizeEvent(QResizeEvent *e) {
+
+  Q_UNUSED(e)
+  canvas_ = QPixmap(size());
+  canvas_.fill(palette().color(QPalette::AlternateBase));
+
+}
+
+void WaveRubber::analyze(QPainter &p, const Scope &s, bool new_frame) {
+
+  if (!new_frame || engine_->state() == EngineBase::State::Paused) {
+    p.drawPixmap(0, 0, canvas_);
+    return;
+  }
+
+  // Clear the canvas
+  canvas_ = QPixmap(size());
+  canvas_.fill(palette().color(QPalette::Window));
+
+  QPainter canvas_painter(&canvas_);
+
+  // Set the pen color to the QT palette highlight color
+  canvas_painter.setPen(palette().color(QPalette::Highlight));
+  // Get pointer to amplitude data 
+  const float *amplitude_data = s.data();
+    
+  int mid_y = height() / 4;
+  int num_samples = s.size();
+  
+  float x_scale = static_cast<float>(width()) / num_samples;
+  float prev_y = mid_y;
+
+  // Draw the waveform
+  for (int i = 0; i < num_samples; ++i) {
+
+    // Normalize amplitude to 0-1 range
+    float color_factor = amplitude_data[i] / 2.0f + 0.5f;
+    int rgb_value = static_cast<int>(255 - color_factor * 255);
+    QColor highlight_color = palette().color(QPalette::Highlight);
+    // Blend blue and green with highlight color from QT palette based on amplitude
+    QColor blended_color = QColor(rgb_value, highlight_color.green(), highlight_color.blue());
+    canvas_painter.setPen(blended_color);
+    
+    int x = static_cast<int>(i * x_scale ); 
+    int y = static_cast<int>(mid_y - (s[i] * mid_y)); 
+
+    canvas_painter.drawLine(x, prev_y + mid_y, x + x_scale, y + mid_y); // Draw
+    prev_y = y;
+  
+  }
+
+  canvas_painter.end();
+  p.drawPixmap(0, 0, canvas_);
+
+}
+
+void WaveRubber::transform(Scope &s) {
+  // No need transformation for waveform analyzer
+  Q_UNUSED(s);
+}
+
+void WaveRubber::demo(QPainter &p) {
+  analyze(p, Scope(fht_->size(), 0), new_frame_);
+}
+

src/analyzer/waverubber.h

@@ -0,0 +1,43 @@
+/*
+   Strawberry Music Player
+   Copyright 2024, Gustavo L Conte <suporte@gu.pro.br>
+
+   Strawberry is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   Strawberry is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+
+#include <QPixmap>
+#include <QPainter>
+
+#include "analyzerbase.h"
+
+class WaveRubber : public AnalyzerBase {
+
+  Q_OBJECT
+ public:
+  Q_INVOKABLE explicit WaveRubber(QWidget *parent);
+
+  static const char *kName;
+
+ protected:
+  void resizeEvent(QResizeEvent *e) override;
+  void analyze(QPainter &p, const Scope &s, bool new_frame) override;
+  void transform(Scope &scope) override;
+  void demo(QPainter &p) override;
+
+ private:
+  QPixmap canvas_;
+
+};
+