screen-cast-session: Add screen-cast window mode

Window mode will cast the content of a single window using the
`MetaScreenCastWindow` interface.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/306

src/Makefile.am

@@ -385,6 +385,10 @@ libmutter_@LIBMUTTER_API_VERSION@_la_SOURCES +=	\
 	backends/meta-screen-cast-monitor-stream.h	\
 	backends/meta-screen-cast-monitor-stream-src.c	\
 	backends/meta-screen-cast-monitor-stream-src.h	\
+	backends/meta-screen-cast-window-stream-src.c	\
+	backends/meta-screen-cast-window-stream-src.h	\
+	backends/meta-screen-cast-window-stream.c	\
+	backends/meta-screen-cast-window-stream.h	\
 	backends/meta-screen-cast-session.c	\
 	backends/meta-screen-cast-session.h	\
 	backends/meta-screen-cast-stream.c	\

src/backends/meta-screen-cast-window-stream-src.c

@@ -0,0 +1,245 @@
+/*
+ * Copyright (C) 2018 Red Hat Inc.
+ *
+ * This program 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 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ *
+ */
+
+#include "config.h"
+
+#include "backends/meta-screen-cast-window-stream-src.h"
+
+#include "backends/meta-backend-private.h"
+#include "backends/meta-screen-cast-window.h"
+#include "backends/meta-screen-cast-window-stream.h"
+#include "compositor/meta-window-actor-private.h"
+
+struct _MetaScreenCastWindowStreamSrc
+{
+  MetaScreenCastStreamSrc parent;
+
+  MetaWindowActor *window_actor;
+
+  unsigned long actor_painted_handler_id;
+  unsigned long actor_destroyed_handler_id;
+};
+
+G_DEFINE_TYPE (MetaScreenCastWindowStreamSrc,
+               meta_screen_cast_window_stream_src,
+               META_TYPE_SCREEN_CAST_STREAM_SRC)
+
+static MetaScreenCastWindowStream *
+get_window_stream (MetaScreenCastWindowStreamSrc *window_src)
+{
+  MetaScreenCastStreamSrc *src;
+  MetaScreenCastStream *stream;
+
+  src = META_SCREEN_CAST_STREAM_SRC (window_src);
+  stream = meta_screen_cast_stream_src_get_stream (src);
+
+  return META_SCREEN_CAST_WINDOW_STREAM (stream);
+}
+
+static MetaWindow *
+get_window (MetaScreenCastWindowStreamSrc *window_src)
+{
+  MetaScreenCastWindowStream *window_stream;
+
+  window_stream = get_window_stream (window_src);
+
+  return meta_screen_cast_window_stream_get_window (window_stream);
+}
+
+static int
+get_stream_width (MetaScreenCastWindowStreamSrc *window_src)
+{
+  MetaScreenCastWindowStream *window_stream;
+
+  window_stream = get_window_stream (window_src);
+
+  return meta_screen_cast_window_stream_get_width (window_stream);
+}
+
+static int
+get_stream_height (MetaScreenCastWindowStreamSrc *window_src)
+{
+  MetaScreenCastWindowStream *window_stream;
+
+  window_stream = get_window_stream (window_src);
+
+  return meta_screen_cast_window_stream_get_height (window_stream);
+}
+
+static gboolean
+capture_into (MetaScreenCastWindowStreamSrc *window_src,
+              uint8_t                       *data)
+{
+  MetaRectangle stream_rect;
+  MetaScreenCastWindow *screen_cast_window;
+
+  stream_rect.x = 0;
+  stream_rect.y = 0;
+  stream_rect.width = get_stream_width (window_src);
+  stream_rect.height = get_stream_height (window_src);
+
+  screen_cast_window = META_SCREEN_CAST_WINDOW (window_src->window_actor);
+  meta_screen_cast_window_capture_into (screen_cast_window, &stream_rect, data);
+
+  return TRUE;
+}
+
+static void
+meta_screen_cast_window_stream_src_get_specs (MetaScreenCastStreamSrc *src,
+                                              int                     *width,
+                                              int                     *height,
+                                              float                   *frame_rate)
+{
+  MetaScreenCastWindowStreamSrc *window_src =
+    META_SCREEN_CAST_WINDOW_STREAM_SRC (src);
+
+  *width = get_stream_width (window_src);
+  *height = get_stream_height (window_src);
+  *frame_rate = 60.0f;
+}
+
+static gboolean
+meta_screen_cast_window_stream_src_get_videocrop (MetaScreenCastStreamSrc *src,
+                                                  MetaRectangle           *crop_rect)
+{
+  MetaScreenCastWindowStreamSrc *window_src =
+    META_SCREEN_CAST_WINDOW_STREAM_SRC (src);
+  MetaScreenCastWindow *screen_cast_window;
+  MetaRectangle stream_rect;
+
+  screen_cast_window = META_SCREEN_CAST_WINDOW (window_src->window_actor);
+  meta_screen_cast_window_get_frame_bounds (screen_cast_window, crop_rect);
+
+  stream_rect.x = 0;
+  stream_rect.y = 0;
+  stream_rect.width = get_stream_width (window_src);
+  stream_rect.height = get_stream_height (window_src);
+
+  meta_rectangle_intersect (crop_rect, &stream_rect, crop_rect);
+
+  return TRUE;
+}
+
+static void
+meta_screen_cast_window_stream_src_stop (MetaScreenCastWindowStreamSrc *window_src)
+
+{
+  if (!window_src->window_actor)
+    return;
+
+  if (window_src->actor_painted_handler_id)
+    g_signal_handler_disconnect (window_src->window_actor,
+                                 window_src->actor_painted_handler_id);
+  window_src->actor_painted_handler_id = 0;
+
+  if (window_src->actor_destroyed_handler_id)
+    g_signal_handler_disconnect (window_src->window_actor,
+                                 window_src->actor_destroyed_handler_id);
+  window_src->actor_destroyed_handler_id = 0;
+}
+
+static void
+window_actor_painted (MetaWindowActor               *actor,
+                      MetaScreenCastWindowStreamSrc *window_src)
+{
+  MetaScreenCastStreamSrc *src = META_SCREEN_CAST_STREAM_SRC (window_src);
+
+  meta_screen_cast_stream_src_maybe_record_frame (src);
+}
+
+static void
+window_actor_destroyed (MetaWindowActor               *actor,
+                        MetaScreenCastWindowStreamSrc *window_src)
+{
+  meta_screen_cast_window_stream_src_stop (window_src);
+  window_src->window_actor = NULL;
+}
+
+static void
+meta_screen_cast_window_stream_src_enable (MetaScreenCastStreamSrc *src)
+{
+  MetaScreenCastWindowStreamSrc *window_src =
+    META_SCREEN_CAST_WINDOW_STREAM_SRC (src);
+  MetaWindowActor *window_actor;
+
+  window_actor = meta_window_actor_from_window (get_window (window_src));
+  if (!window_actor)
+    return;
+
+  window_src->window_actor = window_actor;
+
+  window_src->actor_painted_handler_id =
+    g_signal_connect_after (window_src->window_actor,
+                            "paint",
+                            G_CALLBACK (window_actor_painted),
+                            window_src);
+
+  window_src->actor_destroyed_handler_id =
+    g_signal_connect (window_src->window_actor,
+                      "destroy",
+                      G_CALLBACK (window_actor_destroyed),
+                      window_src);
+}
+
+static void
+meta_screen_cast_window_stream_src_disable (MetaScreenCastStreamSrc *src)
+{
+  MetaScreenCastWindowStreamSrc *window_src =
+    META_SCREEN_CAST_WINDOW_STREAM_SRC (src);
+
+  meta_screen_cast_window_stream_src_stop (window_src);
+}
+
+static void
+meta_screen_cast_window_stream_src_record_frame (MetaScreenCastStreamSrc *src,
+                                                 uint8_t                 *data)
+{
+  MetaScreenCastWindowStreamSrc *window_src =
+    META_SCREEN_CAST_WINDOW_STREAM_SRC (src);
+
+  capture_into (window_src, data);
+}
+
+MetaScreenCastWindowStreamSrc *
+meta_screen_cast_window_stream_src_new (MetaScreenCastWindowStream  *window_stream,
+                                        GError                     **error)
+{
+  return g_initable_new (META_TYPE_SCREEN_CAST_WINDOW_STREAM_SRC, NULL, error,
+                         "stream", window_stream,
+                         NULL);
+}
+
+static void
+meta_screen_cast_window_stream_src_init (MetaScreenCastWindowStreamSrc *window_src)
+{
+}
+
+static void
+meta_screen_cast_window_stream_src_class_init (MetaScreenCastWindowStreamSrcClass *klass)
+{
+  MetaScreenCastStreamSrcClass *src_class =
+    META_SCREEN_CAST_STREAM_SRC_CLASS (klass);
+
+  src_class->get_specs = meta_screen_cast_window_stream_src_get_specs;
+  src_class->enable = meta_screen_cast_window_stream_src_enable;
+  src_class->disable = meta_screen_cast_window_stream_src_disable;
+  src_class->record_frame = meta_screen_cast_window_stream_src_record_frame;
+  src_class->get_videocrop = meta_screen_cast_window_stream_src_get_videocrop;
+}

src/backends/meta-screen-cast-window-stream-src.h

@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2018 Red Hat Inc.
+ *
+ * This program 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 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ *
+ */
+
+#ifndef META_SCREEN_CAST_WINDOW_STREAM_SRC_H
+#define META_SCREEN_CAST_WINDOW_STREAM_SRC_H
+
+#include "backends/meta-screen-cast-stream-src.h"
+
+typedef struct _MetaScreenCastWindowStream MetaScreenCastWindowStream;
+
+#define META_TYPE_SCREEN_CAST_WINDOW_STREAM_SRC (meta_screen_cast_window_stream_src_get_type ())
+G_DECLARE_FINAL_TYPE (MetaScreenCastWindowStreamSrc,
+                      meta_screen_cast_window_stream_src,
+                      META, SCREEN_CAST_WINDOW_STREAM_SRC,
+                      MetaScreenCastStreamSrc)
+
+MetaScreenCastWindowStreamSrc * meta_screen_cast_window_stream_src_new (MetaScreenCastWindowStream  *window_stream,
+                                                                        GError                     **error);
+
+#endif /* META_SCREEN_CAST_WINDOW_STREAM_SRC_H */

src/backends/meta-screen-cast-window-stream.c

@@ -0,0 +1,270 @@
+/*
+ * Copyright (C) 2018 Red Hat Inc.
+ *
+ * This program 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 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ *
+ */
+
+#include "config.h"
+
+#include "backends/meta-screen-cast-window-stream.h"
+
+#include "backends/meta-logical-monitor.h"
+#include "backends/meta-monitor-manager-private.h"
+#include "backends/meta-screen-cast-window.h"
+#include "backends/meta-screen-cast-window-stream-src.h"
+#include "compositor/meta-window-actor-private.h"
+#include "core/window-private.h"
+
+enum
+{
+  PROP_0,
+
+  PROP_WINDOW,
+};
+
+struct _MetaScreenCastWindowStream
+{
+  MetaScreenCastStream parent;
+
+  MetaWindow *window;
+
+  int stream_width;
+  int stream_height;
+
+  unsigned long window_unmanaged_handler_id;
+};
+
+G_DEFINE_TYPE (MetaScreenCastWindowStream,
+               meta_screen_cast_window_stream,
+               META_TYPE_SCREEN_CAST_STREAM)
+
+MetaWindow *
+meta_screen_cast_window_stream_get_window (MetaScreenCastWindowStream *window_stream)
+{
+  return window_stream->window;
+}
+
+int
+meta_screen_cast_window_stream_get_width (MetaScreenCastWindowStream *window_stream)
+{
+  return window_stream->stream_width;
+}
+
+int
+meta_screen_cast_window_stream_get_height (MetaScreenCastWindowStream *window_stream)
+{
+  return window_stream->stream_height;
+}
+
+MetaScreenCastWindowStream *
+meta_screen_cast_window_stream_new (GDBusConnection  *connection,
+                                    MetaWindow       *window,
+                                    GError          **error)
+{
+  MetaScreenCastWindowStream *window_stream;
+  MetaLogicalMonitor *logical_monitor;
+  int scale;
+
+  logical_monitor = meta_window_get_main_logical_monitor (window);
+  if (!logical_monitor)
+    {
+      g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                   "Main logical monitor not found");
+      return NULL;
+    }
+
+  window_stream = g_initable_new (META_TYPE_SCREEN_CAST_WINDOW_STREAM,
+                                  NULL,
+                                  error,
+                                  "connection", connection,
+                                  "window", window,
+                                  NULL);
+  if (!window_stream)
+    return NULL;
+
+  window_stream->window = window;
+  /* We cannot set the stream size to the exact size of the window, because
+   * windows can be resized, whereas streams cannot.
+   * So we set a size equals to the size of the logical monitor for the window.
+   */
+  scale = (int) ceil (meta_logical_monitor_get_scale (logical_monitor));
+  window_stream->stream_width = logical_monitor->rect.width * scale;
+  window_stream->stream_height = logical_monitor->rect.height * scale;
+
+  return window_stream;
+}
+
+static MetaScreenCastStreamSrc *
+meta_screen_cast_window_stream_create_src (MetaScreenCastStream  *stream,
+                                           GError               **error)
+{
+  MetaScreenCastWindowStream *window_stream =
+    META_SCREEN_CAST_WINDOW_STREAM (stream);
+  MetaScreenCastWindowStreamSrc *window_stream_src;
+
+  window_stream_src = meta_screen_cast_window_stream_src_new (window_stream,
+                                                              error);
+  if (!window_stream_src)
+    return NULL;
+
+  return META_SCREEN_CAST_STREAM_SRC (window_stream_src);
+}
+
+static void
+meta_screen_cast_window_stream_set_parameters (MetaScreenCastStream *stream,
+                                               GVariantBuilder      *parameters_builder)
+{
+  MetaScreenCastWindowStream *window_stream =
+    META_SCREEN_CAST_WINDOW_STREAM (stream);
+  MetaScreenCastWindow *screen_cast_window =
+    META_SCREEN_CAST_WINDOW (meta_window_actor_from_window (window_stream->window));
+  MetaRectangle bounds;
+
+  meta_screen_cast_window_get_buffer_bounds (screen_cast_window, &bounds);
+
+  g_variant_builder_add (parameters_builder, "{sv}",
+                         "position",
+                         g_variant_new ("(ii)",
+                                        bounds.x, bounds.y));
+
+  g_variant_builder_add (parameters_builder, "{sv}",
+                         "size",
+                         g_variant_new ("(ii)",
+                                        bounds.width,
+                                        bounds.height));
+}
+
+static void
+meta_screen_cast_window_stream_transform_position (MetaScreenCastStream *stream,
+                                                   double                stream_x,
+                                                   double                stream_y,
+                                                   double               *x,
+                                                   double               *y)
+{
+  MetaScreenCastWindowStream *window_stream =
+    META_SCREEN_CAST_WINDOW_STREAM (stream);
+  MetaScreenCastWindow *screen_cast_window =
+    META_SCREEN_CAST_WINDOW (meta_window_actor_from_window (window_stream->window));
+
+  meta_screen_cast_window_transform_relative_position (screen_cast_window,
+                                                       stream_x,
+                                                       stream_y,
+                                                       x,
+                                                       y);
+}
+
+static void
+on_window_unmanaged (MetaScreenCastWindowStream *window_stream)
+{
+  meta_screen_cast_stream_close (META_SCREEN_CAST_STREAM (window_stream));
+}
+
+static void
+meta_screen_cast_window_stream_constructed (GObject *object)
+{
+  MetaScreenCastWindowStream *window_stream =
+    META_SCREEN_CAST_WINDOW_STREAM (object);
+
+  window_stream->window_unmanaged_handler_id =
+    g_signal_connect_swapped (window_stream->window, "unmanaged",
+                              G_CALLBACK (on_window_unmanaged),
+                              window_stream);
+
+  G_OBJECT_CLASS (meta_screen_cast_window_stream_parent_class)->constructed (object);
+}
+
+static void
+meta_screen_cast_window_stream_set_property (GObject      *object,
+                                             guint         prop_id,
+                                             const GValue *value,
+                                             GParamSpec   *pspec)
+{
+  MetaScreenCastWindowStream *window_stream =
+    META_SCREEN_CAST_WINDOW_STREAM (object);
+
+  switch (prop_id)
+    {
+    case PROP_WINDOW:
+      window_stream->window = g_value_get_object (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+meta_screen_cast_window_stream_get_property (GObject    *object,
+                                             guint       prop_id,
+                                             GValue     *value,
+                                             GParamSpec *pspec)
+{
+  MetaScreenCastWindowStream *window_stream =
+    META_SCREEN_CAST_WINDOW_STREAM (object);
+
+  switch (prop_id)
+    {
+    case PROP_WINDOW:
+      g_value_set_object (value, window_stream->window);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+meta_screen_cast_window_stream_finalize (GObject *object)
+{
+  MetaScreenCastWindowStream *window_stream =
+    META_SCREEN_CAST_WINDOW_STREAM (object);
+
+  g_signal_handler_disconnect (window_stream->window,
+                               window_stream->window_unmanaged_handler_id);
+
+  G_OBJECT_CLASS (meta_screen_cast_window_stream_parent_class)->finalize (object);
+}
+
+static void
+meta_screen_cast_window_stream_init (MetaScreenCastWindowStream *window_stream)
+{
+}
+
+static void
+meta_screen_cast_window_stream_class_init (MetaScreenCastWindowStreamClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+  MetaScreenCastStreamClass *stream_class =
+    META_SCREEN_CAST_STREAM_CLASS (klass);
+
+  object_class->constructed = meta_screen_cast_window_stream_constructed;
+  object_class->set_property = meta_screen_cast_window_stream_set_property;
+  object_class->get_property = meta_screen_cast_window_stream_get_property;
+  object_class->finalize = meta_screen_cast_window_stream_finalize;
+
+  stream_class->create_src = meta_screen_cast_window_stream_create_src;
+  stream_class->set_parameters = meta_screen_cast_window_stream_set_parameters;
+  stream_class->transform_position = meta_screen_cast_window_stream_transform_position;
+
+  g_object_class_install_property (object_class,
+                                   PROP_WINDOW,
+                                   g_param_spec_object ("window",
+                                                        "window",
+                                                        "MetaWindow",
+                                                        META_TYPE_WINDOW,
+                                                        G_PARAM_READWRITE |
+                                                        G_PARAM_CONSTRUCT_ONLY |
+                                                        G_PARAM_STATIC_STRINGS));
+}

src/backends/meta-screen-cast-window-stream.h

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2018 Red Hat Inc.
+ *
+ * This program 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 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ *
+ */
+
+#ifndef META_SCREEN_CAST_WINDOW_STREAM_H
+#define META_SCREEN_CAST_WINDOW_STREAM_H
+
+#include <glib-object.h>
+
+#include "backends/meta-screen-cast-stream.h"
+#include "meta/window.h"
+
+#define META_TYPE_SCREEN_CAST_WINDOW_STREAM (meta_screen_cast_window_stream_get_type ())
+G_DECLARE_FINAL_TYPE (MetaScreenCastWindowStream,
+                      meta_screen_cast_window_stream,
+                      META, SCREEN_CAST_WINDOW_STREAM,
+                      MetaScreenCastStream)
+
+MetaScreenCastWindowStream * meta_screen_cast_window_stream_new (GDBusConnection  *connection,
+                                                                 MetaWindow       *window,
+                                                                 GError          **error);
+
+MetaWindow  * meta_screen_cast_window_stream_get_window (MetaScreenCastWindowStream *window_stream);
+int           meta_screen_cast_window_stream_get_width  (MetaScreenCastWindowStream *window_stream);
+int           meta_screen_cast_window_stream_get_height (MetaScreenCastWindowStream *window_stream);
+
+#endif /* META_SCREEN_CAST_WINDOW_STREAM_H */

src/meson.build

@@ -413,6 +413,10 @@ if have_remote_desktop
     'backends/meta-screen-cast-monitor-stream.h',
     'backends/meta-screen-cast-monitor-stream-src.c',
     'backends/meta-screen-cast-monitor-stream-src.h',
+    'backends/meta-screen-cast-window-stream-src.c',
+    'backends/meta-screen-cast-window-stream-src.h',
+    'backends/meta-screen-cast-window-stream.c',
+    'backends/meta-screen-cast-window-stream.h',
     'backends/meta-screen-cast-session.c',
     'backends/meta-screen-cast-session.h',
     'backends/meta-screen-cast-stream.c',