gstreamer/ext/qt/qtitem.cc
Matthew Waters 612102fdbc gst: don't use volatile to mean atomic
volatile is not sufficient to provide atomic guarantees and real atomics
should be used instead.  GCC 11 has started warning about using volatile
with atomic operations.

https://gitlab.gnome.org/GNOME/glib/-/merge_requests/1719

Discovered in https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/issues/868

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/911>
2021-03-18 19:52:53 +11:00

620 lines
16 KiB
C++

/*
* GStreamer
* Copyright (C) 2015 Matthew Waters <matthew@centricular.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdio.h>
#include <gst/video/video.h>
#include "qtitem.h"
#include "gstqsgtexture.h"
#include "gstqtglutility.h"
#include <QtCore/QRunnable>
#include <QtCore/QMutexLocker>
#include <QtCore/QPointer>
#include <QtGui/QGuiApplication>
#include <QtQuick/QQuickWindow>
#include <QtQuick/QSGSimpleTextureNode>
/**
* SECTION:gtkgstglwidget
* @short_description: a #GtkGLArea that renders GStreamer video #GstBuffers
* @see_also: #GtkGLArea, #GstBuffer
*
* #QtGLVideoItem is an #QQuickItem that renders GStreamer video buffers.
*/
#define GST_CAT_DEFAULT qt_item_debug
GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
#define DEFAULT_FORCE_ASPECT_RATIO TRUE
#define DEFAULT_PAR_N 0
#define DEFAULT_PAR_D 1
enum
{
PROP_0,
PROP_FORCE_ASPECT_RATIO,
PROP_PIXEL_ASPECT_RATIO,
};
struct _QtGLVideoItemPrivate
{
GMutex lock;
/* properties */
gboolean force_aspect_ratio;
gint par_n, par_d;
gint display_width;
gint display_height;
gboolean negotiated;
GstBuffer *buffer;
GstCaps *caps;
GstVideoInfo v_info;
gboolean initted;
GstGLDisplay *display;
QOpenGLContext *qt_context;
GstGLContext *other_context;
GstGLContext *context;
/* buffers with textures that were bound by QML */
GQueue bound_buffers;
/* buffers that were previously bound but in the meantime a new one was
* bound so this one is most likely not used anymore
* FIXME: Ideally we would use fences for this but there seems to be no
* way to reliably "try wait" on a fence */
GQueue potentially_unbound_buffers;
};
class InitializeSceneGraph : public QRunnable
{
public:
InitializeSceneGraph(QtGLVideoItem *item);
void run();
private:
QPointer<QtGLVideoItem> item_;
};
InitializeSceneGraph::InitializeSceneGraph(QtGLVideoItem *item) :
item_(item)
{
}
void InitializeSceneGraph::run()
{
if(item_)
item_->onSceneGraphInitialized();
}
QtGLVideoItem::QtGLVideoItem()
{
static gsize _debug;
if (g_once_init_enter (&_debug)) {
GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT, "qtglwidget", 0, "Qt GL Widget");
g_once_init_leave (&_debug, 1);
}
this->m_openGlContextInitialized = false;
this->setFlag (QQuickItem::ItemHasContents, true);
this->priv = g_new0 (QtGLVideoItemPrivate, 1);
this->priv->force_aspect_ratio = DEFAULT_FORCE_ASPECT_RATIO;
this->priv->par_n = DEFAULT_PAR_N;
this->priv->par_d = DEFAULT_PAR_D;
g_mutex_init (&this->priv->lock);
this->priv->display = gst_qt_get_gl_display();
connect(this, SIGNAL(windowChanged(QQuickWindow*)), this,
SLOT(handleWindowChanged(QQuickWindow*)));
this->proxy = QSharedPointer<QtGLVideoItemInterface>(new QtGLVideoItemInterface(this));
GST_DEBUG ("%p init Qt Video Item", this);
}
QtGLVideoItem::~QtGLVideoItem()
{
/* Before destroying the priv info, make sure
* no qmlglsink's will call in again, and that
* any ongoing calls are done by invalidating the proxy
* pointer */
GST_INFO ("%p Destroying QtGLVideoItem and invalidating the proxy %p", this, proxy.data());
proxy->invalidateRef();
proxy.clear();
g_mutex_clear (&this->priv->lock);
if (this->priv->context)
gst_object_unref(this->priv->context);
if (this->priv->other_context)
gst_object_unref(this->priv->other_context);
if (this->priv->display)
gst_object_unref(this->priv->display);
gst_buffer_replace (&this->priv->buffer, NULL);
gst_caps_replace (&this->priv->caps, NULL);
g_free (this->priv);
this->priv = NULL;
}
void
QtGLVideoItem::setDAR(gint num, gint den)
{
this->priv->par_n = num;
this->priv->par_d = den;
}
void
QtGLVideoItem::getDAR(gint * num, gint * den)
{
if (num)
*num = this->priv->par_n;
if (den)
*den = this->priv->par_d;
}
void
QtGLVideoItem::setForceAspectRatio(bool force_aspect_ratio)
{
this->priv->force_aspect_ratio = !!force_aspect_ratio;
}
bool
QtGLVideoItem::getForceAspectRatio()
{
return this->priv->force_aspect_ratio;
}
bool
QtGLVideoItem::itemInitialized()
{
return m_openGlContextInitialized;
}
QSGNode *
QtGLVideoItem::updatePaintNode(QSGNode * oldNode,
UpdatePaintNodeData * updatePaintNodeData)
{
GstBuffer *old_buffer;
gboolean was_bound = FALSE;
if (!m_openGlContextInitialized) {
return oldNode;
}
QSGSimpleTextureNode *texNode = static_cast<QSGSimpleTextureNode *> (oldNode);
GstVideoRectangle src, dst, result;
GstQSGTexture *tex;
g_mutex_lock (&this->priv->lock);
if (gst_gl_context_get_current() == NULL)
gst_gl_context_activate (this->priv->other_context, TRUE);
GST_TRACE ("%p updatePaintNode", this);
if (!this->priv->caps) {
g_mutex_unlock (&this->priv->lock);
return NULL;
}
if (!texNode) {
texNode = new QSGSimpleTextureNode ();
texNode->setOwnsTexture (true);
texNode->setTexture (new GstQSGTexture ());
}
tex = static_cast<GstQSGTexture *> (texNode->texture());
if ((old_buffer = tex->getBuffer(&was_bound))) {
if (old_buffer == this->priv->buffer) {
/* same buffer */
gst_buffer_unref (old_buffer);
} else if (!was_bound) {
GST_TRACE ("old buffer %p was not bound yet, unreffing", old_buffer);
gst_buffer_unref (old_buffer);
} else {
GstBuffer *tmp_buffer;
GST_TRACE ("old buffer %p was bound, queueing up for later", old_buffer);
/* Unref all buffers that were previously not bound anymore. At least
* one more buffer was bound in the meantime so this one is most likely
* not in use anymore. */
while ((tmp_buffer = (GstBuffer*) g_queue_pop_head (&this->priv->potentially_unbound_buffers))) {
GST_TRACE ("old buffer %p should be unbound now, unreffing", tmp_buffer);
gst_buffer_unref (tmp_buffer);
}
/* Move previous bound buffers to the next queue. We now know that
* another buffer was bound in the meantime and will free them on
* the next iteration above. */
while ((tmp_buffer = (GstBuffer*) g_queue_pop_head (&this->priv->bound_buffers))) {
GST_TRACE ("old buffer %p is potentially unbound now", tmp_buffer);
g_queue_push_tail (&this->priv->potentially_unbound_buffers, tmp_buffer);
}
g_queue_push_tail (&this->priv->bound_buffers, old_buffer);
}
old_buffer = NULL;
}
tex->setCaps (this->priv->caps);
tex->setBuffer (this->priv->buffer);
texNode->markDirty(QSGNode::DirtyMaterial);
if (this->priv->force_aspect_ratio) {
src.w = this->priv->display_width;
src.h = this->priv->display_height;
dst.x = boundingRect().x();
dst.y = boundingRect().y();
dst.w = boundingRect().width();
dst.h = boundingRect().height();
gst_video_sink_center_rect (src, dst, &result, TRUE);
} else {
result.x = boundingRect().x();
result.y = boundingRect().y();
result.w = boundingRect().width();
result.h = boundingRect().height();
}
texNode->setRect (QRectF (result.x, result.y, result.w, result.h));
g_mutex_unlock (&this->priv->lock);
return texNode;
}
static void
_reset (QtGLVideoItem * qt_item)
{
GstBuffer *tmp_buffer;
gst_buffer_replace (&qt_item->priv->buffer, NULL);
gst_caps_replace (&qt_item->priv->caps, NULL);
qt_item->priv->negotiated = FALSE;
qt_item->priv->initted = FALSE;
while ((tmp_buffer = (GstBuffer*) g_queue_pop_head (&qt_item->priv->potentially_unbound_buffers))) {
GST_TRACE ("old buffer %p should be unbound now, unreffing", tmp_buffer);
gst_buffer_unref (tmp_buffer);
}
while ((tmp_buffer = (GstBuffer*) g_queue_pop_head (&qt_item->priv->bound_buffers))) {
GST_TRACE ("old buffer %p should be unbound now, unreffing", tmp_buffer);
gst_buffer_unref (tmp_buffer);
}
}
void
QtGLVideoItemInterface::setBuffer (GstBuffer * buffer)
{
QMutexLocker locker(&lock);
if (qt_item == NULL) {
GST_WARNING ("%p actual item is NULL. setBuffer call ignored", this);
return;
}
if (!qt_item->priv->negotiated) {
GST_WARNING ("%p Got buffer on unnegotiated QtGLVideoItem. Dropping", this);
return;
}
g_mutex_lock (&qt_item->priv->lock);
gst_buffer_replace (&qt_item->priv->buffer, buffer);
QMetaObject::invokeMethod(qt_item, "update", Qt::QueuedConnection);
g_mutex_unlock (&qt_item->priv->lock);
}
void
QtGLVideoItem::onSceneGraphInitialized ()
{
if (this->window() == NULL)
return;
GST_DEBUG ("%p scene graph initialization with Qt GL context %p", this,
this->window()->openglContext ());
if (this->priv->qt_context == this->window()->openglContext ())
return;
this->priv->qt_context = this->window()->openglContext ();
if (this->priv->qt_context == NULL) {
g_assert_not_reached ();
return;
}
m_openGlContextInitialized = gst_qt_get_gl_wrapcontext (this->priv->display,
&this->priv->other_context, &this->priv->context);
GST_DEBUG ("%p created wrapped GL context %" GST_PTR_FORMAT, this,
this->priv->other_context);
emit itemInitializedChanged();
}
void
QtGLVideoItem::onSceneGraphInvalidated ()
{
GST_FIXME ("%p scene graph invalidated", this);
}
/**
* Retrieve and populate the GL context information from the current
* OpenGL context.
*/
gboolean
QtGLVideoItemInterface::initWinSys ()
{
QMutexLocker locker(&lock);
GError *error = NULL;
if (qt_item == NULL)
return FALSE;
g_mutex_lock (&qt_item->priv->lock);
if (qt_item->priv->display && qt_item->priv->qt_context
&& qt_item->priv->other_context && qt_item->priv->context) {
/* already have the necessary state */
g_mutex_unlock (&qt_item->priv->lock);
return TRUE;
}
if (!GST_IS_GL_DISPLAY (qt_item->priv->display)) {
GST_ERROR ("%p failed to retrieve display connection %" GST_PTR_FORMAT,
qt_item, qt_item->priv->display);
g_mutex_unlock (&qt_item->priv->lock);
return FALSE;
}
if (!GST_IS_GL_CONTEXT (qt_item->priv->other_context)) {
GST_ERROR ("%p failed to retrieve wrapped context %" GST_PTR_FORMAT, qt_item,
qt_item->priv->other_context);
g_mutex_unlock (&qt_item->priv->lock);
return FALSE;
}
qt_item->priv->context = gst_gl_context_new (qt_item->priv->display);
if (!qt_item->priv->context) {
g_mutex_unlock (&qt_item->priv->lock);
return FALSE;
}
if (!gst_gl_context_create (qt_item->priv->context, qt_item->priv->other_context,
&error)) {
GST_ERROR ("%s", error->message);
g_mutex_unlock (&qt_item->priv->lock);
return FALSE;
}
g_mutex_unlock (&qt_item->priv->lock);
return TRUE;
}
void
QtGLVideoItem::handleWindowChanged(QQuickWindow *win)
{
if (win) {
if (win->isSceneGraphInitialized())
win->scheduleRenderJob(new InitializeSceneGraph(this), QQuickWindow::BeforeSynchronizingStage);
else
connect(win, SIGNAL(sceneGraphInitialized()), this, SLOT(onSceneGraphInitialized()), Qt::DirectConnection);
connect(win, SIGNAL(sceneGraphInvalidated()), this, SLOT(onSceneGraphInvalidated()), Qt::DirectConnection);
} else {
this->priv->qt_context = NULL;
}
}
static gboolean
_calculate_par (QtGLVideoItem * widget, GstVideoInfo * info)
{
gboolean ok;
gint width, height;
gint par_n, par_d;
gint display_par_n, display_par_d;
guint display_ratio_num, display_ratio_den;
width = GST_VIDEO_INFO_WIDTH (info);
height = GST_VIDEO_INFO_HEIGHT (info);
par_n = GST_VIDEO_INFO_PAR_N (info);
par_d = GST_VIDEO_INFO_PAR_D (info);
if (!par_n)
par_n = 1;
/* get display's PAR */
if (widget->priv->par_n != 0 && widget->priv->par_d != 0) {
display_par_n = widget->priv->par_n;
display_par_d = widget->priv->par_d;
} else {
display_par_n = 1;
display_par_d = 1;
}
ok = gst_video_calculate_display_ratio (&display_ratio_num,
&display_ratio_den, width, height, par_n, par_d, display_par_n,
display_par_d);
if (!ok)
return FALSE;
widget->setImplicitWidth (width);
widget->setImplicitHeight (height);
GST_LOG ("%p PAR: %u/%u DAR:%u/%u", widget, par_n, par_d, display_par_n,
display_par_d);
if (height % display_ratio_den == 0) {
GST_DEBUG ("%p keeping video height", widget);
widget->priv->display_width = (guint)
gst_util_uint64_scale_int (height, display_ratio_num,
display_ratio_den);
widget->priv->display_height = height;
} else if (width % display_ratio_num == 0) {
GST_DEBUG ("%p keeping video width", widget);
widget->priv->display_width = width;
widget->priv->display_height = (guint)
gst_util_uint64_scale_int (width, display_ratio_den, display_ratio_num);
} else {
GST_DEBUG ("%p approximating while keeping video height", widget);
widget->priv->display_width = (guint)
gst_util_uint64_scale_int (height, display_ratio_num,
display_ratio_den);
widget->priv->display_height = height;
}
GST_DEBUG ("%p scaling to %dx%d", widget, widget->priv->display_width,
widget->priv->display_height);
return TRUE;
}
gboolean
QtGLVideoItemInterface::setCaps (GstCaps * caps)
{
QMutexLocker locker(&lock);
GstVideoInfo v_info;
g_return_val_if_fail (GST_IS_CAPS (caps), FALSE);
g_return_val_if_fail (gst_caps_is_fixed (caps), FALSE);
if (qt_item == NULL)
return FALSE;
if (qt_item->priv->caps && gst_caps_is_equal_fixed (qt_item->priv->caps, caps))
return TRUE;
if (!gst_video_info_from_caps (&v_info, caps))
return FALSE;
g_mutex_lock (&qt_item->priv->lock);
_reset (qt_item);
gst_caps_replace (&qt_item->priv->caps, caps);
if (!_calculate_par (qt_item, &v_info)) {
g_mutex_unlock (&qt_item->priv->lock);
return FALSE;
}
qt_item->priv->v_info = v_info;
qt_item->priv->negotiated = TRUE;
g_mutex_unlock (&qt_item->priv->lock);
return TRUE;
}
GstGLContext *
QtGLVideoItemInterface::getQtContext ()
{
QMutexLocker locker(&lock);
if (!qt_item || !qt_item->priv->other_context)
return NULL;
return (GstGLContext *) gst_object_ref (qt_item->priv->other_context);
}
GstGLContext *
QtGLVideoItemInterface::getContext ()
{
QMutexLocker locker(&lock);
if (!qt_item || !qt_item->priv->context)
return NULL;
return (GstGLContext *) gst_object_ref (qt_item->priv->context);
}
GstGLDisplay *
QtGLVideoItemInterface::getDisplay()
{
QMutexLocker locker(&lock);
if (!qt_item || !qt_item->priv->display)
return NULL;
return (GstGLDisplay *) gst_object_ref (qt_item->priv->display);
}
void
QtGLVideoItemInterface::setDAR(gint num, gint den)
{
QMutexLocker locker(&lock);
if (!qt_item)
return;
qt_item->setDAR(num, den);
}
void
QtGLVideoItemInterface::getDAR(gint * num, gint * den)
{
QMutexLocker locker(&lock);
if (!qt_item)
return;
qt_item->getDAR (num, den);
}
void
QtGLVideoItemInterface::setForceAspectRatio(bool force_aspect_ratio)
{
QMutexLocker locker(&lock);
if (!qt_item)
return;
qt_item->setForceAspectRatio(force_aspect_ratio);
}
bool
QtGLVideoItemInterface::getForceAspectRatio()
{
QMutexLocker locker(&lock);
if (!qt_item)
return FALSE;
return qt_item->getForceAspectRatio();
}
void
QtGLVideoItemInterface::invalidateRef()
{
QMutexLocker locker(&lock);
qt_item = NULL;
}