Add the smoother demo client

tests/CMakeLists.txt

@@ -54,6 +54,11 @@ if(JACK_FOUND AND TARGET Qt5::Widgets)
     target_link_libraries(sfizz_demo_filters PRIVATE sfizz::sfizz Qt5::Widgets ${JACK_LIBRARIES})
     set_target_properties(sfizz_demo_filters PROPERTIES AUTOUIC ON)
 
+    add_executable(sfizz_demo_smooth DemoSmooth.cpp)
+    target_include_directories(sfizz_demo_smooth PRIVATE ${JACK_INCLUDE_DIRS})
+    target_link_libraries(sfizz_demo_smooth PRIVATE sfizz::sfizz Qt5::Widgets ${JACK_LIBRARIES})
+    set_target_properties(sfizz_demo_smooth PROPERTIES AUTOUIC ON)
+
     add_executable(sfizz_demo_stereo DemoStereo.cpp)
     target_include_directories(sfizz_demo_stereo PRIVATE ${JACK_INCLUDE_DIRS})
     target_link_libraries(sfizz_demo_stereo PRIVATE sfizz::sfizz Qt5::Widgets ${JACK_LIBRARIES})

tests/DemoSmooth.cpp

@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: BSD-2-Clause
+
+// This code is part of the sfizz library and is licensed under a BSD 2-clause
+// license. You should have receive a LICENSE.md file along with the code.
+// If not, contact the sfizz maintainers at https://github.com/sfztools/sfizz
+
+#include "sfizz/Smoothers.h"
+#include "sfizz/MathHelpers.h"
+#include "ui_DemoSmooth.h"
+#include <QApplication>
+#include <QMainWindow>
+#include <QMessageBox>
+#include <QButtonGroup>
+#include <QDebug>
+#include <jack/jack.h>
+#include <memory>
+#include <cmath>
+
+///
+struct jack_delete {
+    void operator()(jack_client_t* x) const noexcept { jack_client_close(x); }
+};
+
+typedef std::unique_ptr<jack_client_t, jack_delete> jack_client_u;
+
+///
+class DemoApp : public QApplication {
+public:
+    DemoApp(int& argc, char** argv);
+    bool initSound();
+    void initWindow();
+
+private:
+    static int processAudio(jack_nframes_t nframes, void* cbdata);
+
+private:
+    void valueChangedSmooth(int value);
+
+private:
+    QMainWindow* fWindow = nullptr;
+    Ui::DemoSmoothWindow fUi;
+
+    static constexpr int smoothMin = 0;
+    static constexpr int smoothMax = 100;
+
+    int fSmooth = 0;
+
+    sfz::Smoother fFilter;
+
+    jack_client_u fClient;
+    jack_port_t* fPorts[2] = {};
+};
+
+DemoApp::DemoApp(int& argc, char** argv)
+    : QApplication(argc, argv)
+{
+    setApplicationName(tr("Sfizz Smooth"));
+}
+
+bool DemoApp::initSound()
+{
+    jack_client_t* client = jack_client_open(
+        applicationName().toUtf8().data(), JackNoStartServer, nullptr);
+    if (!client) {
+        QMessageBox::critical(nullptr, tr("Error"), tr("Cannot open JACK audio."));
+        return false;
+    }
+
+    fClient.reset(client);
+
+    double sampleRate = jack_get_sample_rate(client);
+    fFilter.setSmoothing(fSmooth, sampleRate);
+
+    fPorts[0] = jack_port_register(client, "in", JACK_DEFAULT_AUDIO_TYPE, JackPortIsInput, 0);
+    fPorts[1] = jack_port_register(client, "out", JACK_DEFAULT_AUDIO_TYPE, JackPortIsOutput, 0);
+
+    if (!(fPorts[0] && fPorts[1])) {
+        QMessageBox::critical(nullptr, tr("Error"), tr("Cannot register JACK ports."));
+        return false;
+    }
+
+    jack_set_process_callback(client, &processAudio, this);
+
+    if (jack_activate(client) != 0) {
+        QMessageBox::critical(nullptr, tr("Error"), tr("Cannot activate JACK client."));
+        return false;
+    }
+
+    return true;
+}
+
+void DemoApp::initWindow()
+{
+    QMainWindow* window = new QMainWindow;
+    fWindow = window;
+    fUi.setupUi(window);
+    window->setWindowTitle(applicationDisplayName());
+
+    fUi.dialSmooth->setRange(smoothMin, smoothMax);
+    fUi.spinSmooth->setRange(smoothMin, smoothMax);
+
+    fUi.dialSmooth->setValue(fSmooth);
+    fUi.spinSmooth->setValue(fSmooth);
+
+    connect(
+        fUi.dialSmooth, &QDial::valueChanged,
+        this, [this](int value) { valueChangedSmooth(value); });
+    connect(
+        fUi.spinSmooth, QOverload<int>::of(&QSpinBox::valueChanged),
+        this, [this](int value) { valueChangedSmooth(value); });
+
+    window->adjustSize();
+    window->setFixedSize(window->size());
+
+    window->show();
+}
+
+int DemoApp::processAudio(jack_nframes_t nframes, void* cbdata)
+{
+    DemoApp* self = reinterpret_cast<DemoApp*>(cbdata);
+
+    const float* in = reinterpret_cast<float*>(jack_port_get_buffer(self->fPorts[0], nframes));
+    float* out = reinterpret_cast<float*>(jack_port_get_buffer(self->fPorts[1], nframes));
+
+    self->fFilter.process(absl::MakeSpan(in, nframes), absl::MakeSpan(out, nframes));
+    return 0;
+}
+
+void DemoApp::valueChangedSmooth(int value)
+{
+    fUi.dialSmooth->blockSignals(true);
+    fUi.dialSmooth->setValue(value);
+    fUi.dialSmooth->blockSignals(false);
+
+    fUi.spinSmooth->blockSignals(true);
+    fUi.spinSmooth->setValue(value);
+    fUi.spinSmooth->blockSignals(false);
+
+    fSmooth = value;
+
+    double sampleRate = jack_get_sample_rate(fClient.get());
+    fFilter.setSmoothing(fSmooth, sampleRate);
+}
+
+int main(int argc, char* argv[])
+{
+    DemoApp app(argc, argv);
+
+    if (!app.initSound())
+        return 1;
+
+    app.initWindow();
+
+    return app.exec();
+}

tests/DemoSmooth.ui

@@ -0,0 +1,40 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>DemoSmoothWindow</class>
+ <widget class="QMainWindow" name="DemoSmoothWindow">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>118</width>
+    <height>169</height>
+   </rect>
+  </property>
+  <widget class="QWidget" name="centralwidget">
+   <layout class="QGridLayout" name="gridLayout_4">
+    <item row="1" column="0">
+     <widget class="QSpinBox" name="spinSmooth">
+      <property name="alignment">
+       <set>Qt::AlignCenter</set>
+      </property>
+     </widget>
+    </item>
+    <item row="0" column="0">
+     <widget class="QDial" name="dialSmooth"/>
+    </item>
+    <item row="2" column="0">
+     <widget class="QLabel" name="label">
+      <property name="text">
+       <string>Smooth</string>
+      </property>
+      <property name="alignment">
+       <set>Qt::AlignCenter</set>
+      </property>
+     </widget>
+    </item>
+   </layout>
+  </widget>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>