DOCS/client_api_examples: add qt widget + opengl-cb example

DOCS/client_api_examples/qt_opengl/main.cpp

@@ -0,0 +1,13 @@
+#include <QApplication>
+#include "mainwindow.h"
+
+int main(int argc, char *argv[])
+{
+    QApplication a(argc, argv);
+    // Qt sets the locale in the QApplication constructor, but libmpv requires
+    // the LC_NUMERIC category to be set to "C", so change it back.
+    setlocale(LC_NUMERIC, "C");
+    MainWindow w;
+    w.show();
+    return a.exec();
+}

DOCS/client_api_examples/qt_opengl/mainwindow.cpp

@@ -0,0 +1,53 @@
+#include "mainwindow.h"
+#include "mpvwidget.h"
+#include <QPushButton>
+#include <QSlider>
+#include <QLayout>
+#include <QFileDialog>
+
+MainWindow::MainWindow(QWidget *parent) : QWidget(parent)
+{
+    m_mpv = new MpvWidget(this);
+    m_slider = new QSlider();
+    m_slider->setOrientation(Qt::Horizontal);
+    m_openBtn = new QPushButton("Open");
+    m_playBtn = new QPushButton("Pause");
+    QHBoxLayout *hb = new QHBoxLayout();
+    hb->addWidget(m_openBtn);
+    hb->addWidget(m_playBtn);
+    QVBoxLayout *vl = new QVBoxLayout();
+    vl->addWidget(m_mpv);
+    vl->addWidget(m_slider);
+    vl->addLayout(hb);
+    setLayout(vl);
+    connect(m_slider, SIGNAL(sliderMoved(int)), SLOT(seek(int)));
+    connect(m_openBtn, SIGNAL(clicked()), SLOT(openMedia()));
+    connect(m_playBtn, SIGNAL(clicked()), SLOT(pauseResume()));
+    connect(m_mpv, SIGNAL(positionChanged(int)), m_slider, SLOT(setValue(int)));
+    connect(m_mpv, SIGNAL(durationChanged(int)), this, SLOT(setSliderRange(int)));
+}
+
+void MainWindow::openMedia()
+{
+    QString file = QFileDialog::getOpenFileName(0, "Open a video");
+    if (file.isEmpty())
+        return;
+    m_mpv->command(QStringList() << "loadfile" << file);
+}
+
+void MainWindow::seek(int pos)
+{
+    m_mpv->command(QVariantList() << "seek" << pos << "absolute");
+}
+
+void MainWindow::pauseResume()
+{
+    const bool paused = m_mpv->getProperty("pause").toBool();
+    m_mpv->setProperty("pause", !paused);
+}
+
+void MainWindow::setSliderRange(int duration)
+{
+    const int time0 = m_mpv->getProperty("time-start").toInt();
+    m_slider->setRange(time0, time0+duration);
+}

DOCS/client_api_examples/qt_opengl/mainwindow.h

@@ -0,0 +1,27 @@
+#ifndef MainWindow_H
+#define MainWindow_H
+
+#include <QtWidgets/QWidget>
+
+class MpvWidget;
+class QSlider;
+class QPushButton;
+class MainWindow : public QWidget
+{
+    Q_OBJECT
+public:
+    explicit MainWindow(QWidget *parent = 0);
+public Q_SLOTS:
+    void openMedia();
+    void seek(int pos);
+    void pauseResume();
+private Q_SLOTS:
+    void setSliderRange(int duration);
+private:
+    MpvWidget *m_mpv;
+    QSlider *m_slider;
+    QPushButton *m_openBtn;
+    QPushButton *m_playBtn;
+};
+
+#endif // MainWindow_H

DOCS/client_api_examples/qt_opengl/mpvwidget.cpp

@@ -0,0 +1,128 @@
+#include "mpvwidget.h"
+#include <stdexcept>
+#include <QtGui/QOpenGLContext>
+#include <QtCore/QMetaObject>
+
+static void wakeup(void *ctx)
+{
+    QMetaObject::invokeMethod((MpvWidget*)ctx, "on_mpv_events", Qt::QueuedConnection);
+}
+
+static void *get_proc_address(void *ctx, const char *name) {
+    Q_UNUSED(ctx);
+    QOpenGLContext *glctx = QOpenGLContext::currentContext();
+    if (!glctx)
+        return NULL;
+    return (void *)glctx->getProcAddress(QByteArray(name));
+}
+
+MpvWidget::MpvWidget(QWidget *parent, Qt::WindowFlags f)
+    : QOpenGLWidget(parent, f)
+{
+    mpv = mpv::qt::Handle::FromRawHandle(mpv_create());
+    if (!mpv)
+        throw std::runtime_error("could not create mpv context");
+
+    mpv_set_option_string(mpv, "terminal", "yes");
+    mpv_set_option_string(mpv, "msg-level", "all=v");
+    if (mpv_initialize(mpv) < 0)
+        throw std::runtime_error("could not initialize mpv context");
+
+    // Make use of the MPV_SUB_API_OPENGL_CB API.
+    mpv::qt::set_option_variant(mpv, "vo", "opengl-cb");
+
+    // Request hw decoding, just for testing.
+    mpv::qt::set_option_variant(mpv, "hwdec", "auto");
+
+    mpv_gl = (mpv_opengl_cb_context *)mpv_get_sub_api(mpv, MPV_SUB_API_OPENGL_CB);
+    if (!mpv_gl)
+        throw std::runtime_error("OpenGL not compiled in");
+    mpv_opengl_cb_set_update_callback(mpv_gl, MpvWidget::on_update, (void *)this);
+    connect(this, SIGNAL(frameSwapped()), SLOT(swapped()));
+
+    mpv_observe_property(mpv, 0, "duration", MPV_FORMAT_DOUBLE);
+    mpv_observe_property(mpv, 0, "time-pos", MPV_FORMAT_DOUBLE);
+    mpv_set_wakeup_callback(mpv, wakeup, this);
+}
+
+MpvWidget::~MpvWidget()
+{
+    if (mpv_gl)
+        mpv_opengl_cb_set_update_callback(mpv_gl, NULL, NULL);
+    // Until this call is done, we need to make sure the player remains
+    // alive. This is done implicitly with the mpv::qt::Handle instance
+    // in this class.
+    mpv_opengl_cb_uninit_gl(mpv_gl);
+}
+
+void MpvWidget::command(const QVariant& params)
+{
+    mpv::qt::command_variant(mpv, params);
+}
+
+void MpvWidget::setProperty(const QString& name, const QVariant& value)
+{
+    mpv::qt::set_property_variant(mpv, name, value);
+}
+
+QVariant MpvWidget::getProperty(const QString &name) const
+{
+    return mpv::qt::get_property_variant(mpv, name);
+}
+
+void MpvWidget::initializeGL()
+{
+    int r = mpv_opengl_cb_init_gl(mpv_gl, NULL, get_proc_address, NULL);
+    if (r < 0)
+        throw std::runtime_error("could not initialize OpenGL");
+}
+
+void MpvWidget::paintGL()
+{
+    mpv_opengl_cb_draw(mpv_gl, QOpenGLContext::currentContext()->defaultFramebufferObject(), width(), -height());
+}
+
+void MpvWidget::swapped()
+{
+    mpv_opengl_cb_report_flip(mpv_gl, 0);
+}
+
+void MpvWidget::on_mpv_events()
+{
+    // Process all events, until the event queue is empty.
+    while (mpv) {
+        mpv_event *event = mpv_wait_event(mpv, 0);
+        if (event->event_id == MPV_EVENT_NONE) {
+            break;
+        }
+        handle_mpv_event(event);
+    }
+}
+
+void MpvWidget::handle_mpv_event(mpv_event *event)
+{
+    switch (event->event_id) {
+    case MPV_EVENT_PROPERTY_CHANGE: {
+        mpv_event_property *prop = (mpv_event_property *)event->data;
+        if (strcmp(prop->name, "time-pos") == 0) {
+            if (prop->format == MPV_FORMAT_DOUBLE) {
+                double time = *(double *)prop->data;
+                Q_EMIT positionChanged(time);
+            }
+        } else if (strcmp(prop->name, "duration") == 0) {
+            if (prop->format == MPV_FORMAT_DOUBLE) {
+                double time = *(double *)prop->data;
+                Q_EMIT durationChanged(time);
+            }
+        }
+        break;
+    }
+    default: ;
+        // Ignore uninteresting or unknown events.
+    }
+}
+
+void MpvWidget::on_update(void *ctx)
+{
+    QMetaObject::invokeMethod((MpvWidget*)ctx, "update");
+}

DOCS/client_api_examples/qt_opengl/mpvwidget.h

@@ -0,0 +1,38 @@
+#ifndef PLAYERWINDOW_H
+#define PLAYERWINDOW_H
+
+#include <QtWidgets/QOpenGLWidget>
+#include <mpv/client.h>
+#include <mpv/opengl_cb.h>
+#include <mpv/qthelper.hpp>
+
+class MpvWidget Q_DECL_FINAL: public QOpenGLWidget
+{
+    Q_OBJECT
+public:
+    MpvWidget(QWidget *parent = 0, Qt::WindowFlags f = 0);
+    ~MpvWidget();
+    void command(const QVariant& params);
+    void setProperty(const QString& name, const QVariant& value);
+    QVariant getProperty(const QString& name) const;
+    QSize sizeHint() const { return QSize(480, 270);}
+Q_SIGNALS:
+    void durationChanged(int value);
+    void positionChanged(int value);
+protected:
+    void initializeGL() Q_DECL_OVERRIDE;
+    void paintGL() Q_DECL_OVERRIDE;
+private Q_SLOTS:
+    void swapped();
+    void on_mpv_events();
+private:
+    void handle_mpv_event(mpv_event *event);
+    static void on_update(void *ctx);
+
+    mpv::qt::Handle mpv;
+    mpv_opengl_cb_context *mpv_gl;
+};
+
+
+
+#endif // PLAYERWINDOW_H

DOCS/client_api_examples/qt_opengl/qt_opengl.pro

@@ -0,0 +1,13 @@
+CONFIG -= app_bundle
+QT += widgets
+
+QT_CONFIG -= no-pkg-config
+CONFIG += link_pkgconfig debug
+PKGCONFIG += mpv
+
+HEADERS = \
+    mpvwidget.h \
+    mainwindow.h
+SOURCES = main.cpp \
+    mpvwidget.cpp \
+    mainwindow.cpp