lib: add MksPaintable

This is intended to be connected to a MksScreen and create a Listener to
get DMA-BUF scanout from Qemu.

lib/libmks.h

@@ -30,6 +30,7 @@ G_BEGIN_DECLS
 # include "mks-init.h"
 # include "mks-keyboard.h"
 # include "mks-mouse.h"
+# include "mks-paintable.h"
 # include "mks-screen.h"
 # include "mks-session.h"
 # include "mks-types.h"

lib/meson.build

@@ -3,6 +3,7 @@ libmks_sources = [
   'mks-device.c',
   'mks-keyboard.c',
   'mks-mouse.c',
+  'mks-paintable.c',
   'mks-screen.c',
   'mks-session.c',
 ]
@@ -13,6 +14,7 @@ libmks_headers = [
   'mks-init.h',
   'mks-keyboard.h',
   'mks-mouse.h',
+  'mks-paintable.h',
   'mks-screen.h',
   'mks-session.h',
   'mks-types.h',

lib/mks-init.c

@@ -26,6 +26,7 @@
 #include "mks-init.h"
 #include "mks-keyboard.h"
 #include "mks-mouse.h"
+#include "mks-paintable.h"
 #include "mks-qemu.h"
 #include "mks-read-only-list-model-private.h"
 #include "mks-screen.h"
@@ -53,6 +54,7 @@ mks_init_gtypes (void)
   g_type_ensure (MKS_TYPE_DEVICE);
   g_type_ensure (MKS_TYPE_KEYBOARD);
   g_type_ensure (MKS_TYPE_MOUSE);
+  g_type_ensure (MKS_TYPE_PAINTABLE);
   g_type_ensure (MKS_TYPE_SCREEN);
   g_type_ensure (MKS_TYPE_SESSION);
 }

lib/mks-paintable.c

@@ -0,0 +1,226 @@
+/*
+ * mks-paintable.c
+ *
+ * Copyright 2023 Christian Hergert <chergert@redhat.com>
+ *
+ * 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 3 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, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#include "config.h"
+
+#include "mks-paintable.h"
+#include "mks-screen.h"
+
+struct _MksPaintable
+{
+  GObject    parent_instance;
+  MksScreen *screen;
+};
+
+static void paintable_iface_init (GdkPaintableInterface *iface);
+
+G_DEFINE_FINAL_TYPE_WITH_CODE (MksPaintable, mks_paintable, G_TYPE_OBJECT,
+                               G_IMPLEMENT_INTERFACE (GDK_TYPE_PAINTABLE, paintable_iface_init))
+
+enum {
+  PROP_0,
+  PROP_SCREEN,
+  N_PROPS
+};
+
+static GParamSpec *properties [N_PROPS];
+
+GdkPaintable *
+mks_paintable_new (MksScreen *screen)
+{
+  g_return_val_if_fail (MKS_IS_SCREEN (screen), NULL);
+
+  return g_object_new (MKS_TYPE_PAINTABLE,
+                       "screen", screen,
+                       NULL);
+}
+
+static void
+mks_paintable_set_screen (MksPaintable *self,
+                          MksScreen    *screen)
+{
+  g_assert (MKS_IS_PAINTABLE (self));
+  g_assert (MKS_IS_SCREEN (screen));
+
+  if (g_set_object (&self->screen, screen))
+    {
+      g_signal_connect_object (self->screen,
+                               "notify::width",
+                               G_CALLBACK (gdk_paintable_invalidate_size),
+                               self,
+                               G_CONNECT_SWAPPED);
+      g_signal_connect_object (self->screen,
+                               "notify::height",
+                               G_CALLBACK (gdk_paintable_invalidate_size),
+                               self,
+                               G_CONNECT_SWAPPED);
+    }
+}
+
+static void
+mks_paintable_dispose (GObject *object)
+{
+  MksPaintable *self = (MksPaintable *)object;
+
+  g_clear_object (&self->screen);
+
+  G_OBJECT_CLASS (mks_paintable_parent_class)->dispose (object);
+}
+
+static void
+mks_paintable_get_property (GObject    *object,
+                            guint       prop_id,
+                            GValue     *value,
+                            GParamSpec *pspec)
+{
+  MksPaintable *self = MKS_PAINTABLE (object);
+
+  switch (prop_id)
+    {
+    case PROP_SCREEN:
+      g_value_set_object (value, mks_paintable_get_screen (self));
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+mks_paintable_set_property (GObject      *object,
+                            guint         prop_id,
+                            const GValue *value,
+                            GParamSpec   *pspec)
+{
+  MksPaintable *self = MKS_PAINTABLE (object);
+
+  switch (prop_id)
+    {
+    case PROP_SCREEN:
+      mks_paintable_set_screen (self, g_value_get_object (value));
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+mks_paintable_class_init (MksPaintableClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->dispose = mks_paintable_dispose;
+  object_class->get_property = mks_paintable_get_property;
+  object_class->set_property = mks_paintable_set_property;
+
+  properties [PROP_SCREEN] =
+    g_param_spec_object ("screen", NULL, NULL,
+                         MKS_TYPE_SCREEN,
+                         (G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));
+
+  g_object_class_install_properties (object_class, N_PROPS, properties);
+}
+
+static void
+mks_paintable_init (MksPaintable *self)
+{
+}
+
+/**
+ * mks_paintable_get_screen:
+ * @self: a #MksPaintable
+ *
+ * Gets the #MksScreen displayed in the paintable.
+ *
+ * Returns: (nullable) (transfer none): a #MksScreen or %NULL
+ */
+MksScreen *
+mks_paintable_get_screen (MksPaintable *self)
+{
+  g_return_val_if_fail (MKS_IS_PAINTABLE (self), NULL);
+
+  return self->screen;
+}
+
+static int
+mks_paintable_get_intrinsic_height (GdkPaintable *paintable)
+{
+  MksPaintable *self = MKS_PAINTABLE (paintable);
+
+  return self->screen ? mks_screen_get_height (self->screen) : 0;
+}
+
+static int
+mks_paintable_get_intrinsic_width (GdkPaintable *paintable)
+{
+  MksPaintable *self = MKS_PAINTABLE (paintable);
+
+  return self->screen ? mks_screen_get_width (self->screen) : 0;
+}
+
+static double
+mks_paintable_get_intrinsic_aspect_ratio (GdkPaintable *paintable)
+{
+  MksPaintable *self = MKS_PAINTABLE (paintable);
+  double width;
+  double height;
+
+  if (self->screen == NULL)
+    return 1.;
+
+  width = mks_screen_get_width (self->screen);
+  height = mks_screen_get_height (self->screen);
+
+  if (width == 0 || height == 0)
+    return 1;
+
+  return width / height;
+}
+
+static GdkPaintableFlags
+mks_paintable_get_flags (GdkPaintable *paintable)
+{
+  return 0;
+}
+
+static void
+mks_paintable_snapshot (GdkPaintable *paintable,
+                        GdkSnapshot  *snapshot,
+                        double        width,
+                        double        height)
+{
+  MksPaintable *self = (MksPaintable *)paintable;
+
+  g_assert (MKS_IS_PAINTABLE (self));
+  g_assert (GDK_IS_SNAPSHOT (snapshot));
+
+}
+
+static void
+paintable_iface_init (GdkPaintableInterface *iface)
+{
+  iface->get_intrinsic_height = mks_paintable_get_intrinsic_height;
+  iface->get_intrinsic_width = mks_paintable_get_intrinsic_width;
+  iface->get_flags = mks_paintable_get_flags;
+  iface->get_intrinsic_aspect_ratio = mks_paintable_get_intrinsic_aspect_ratio;
+  iface->snapshot = mks_paintable_snapshot;
+}

lib/mks-paintable.h

@@ -0,0 +1,45 @@
+/*
+ * mks-paintable.h
+ *
+ * Copyright 2023 Christian Hergert <chergert@redhat.com>
+ *
+ * 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 3 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, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#pragma once
+
+#if !defined(MKS_INSIDE) && !defined(MKS_COMPILATION)
+# error "Only <libmks.h> can be included directly."
+#endif
+
+#include <gdk/gdk.h>
+
+#include "mks-types.h"
+#include "mks-version-macros.h"
+
+G_BEGIN_DECLS
+
+#define MKS_TYPE_PAINTABLE (mks_paintable_get_type())
+
+MKS_AVAILABLE_IN_ALL
+G_DECLARE_FINAL_TYPE (MksPaintable, mks_paintable, MKS, PAINTABLE, GObject)
+
+MKS_AVAILABLE_IN_ALL
+GdkPaintable *mks_paintable_new        (MksScreen    *screen);
+MKS_AVAILABLE_IN_ALL
+MksScreen    *mks_paintable_get_screen (MksPaintable *self);
+
+G_END_DECLS