clutter: Add color manager type

This type is intended to carry color related state that is "global",
without having to add more and more things to ClutterContext.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3897>

clutter/clutter/clutter-color-manager.c

@@ -0,0 +1,115 @@
+/*
+ * Clutter.
+ *
+ * An OpenGL based 'interactive canvas' library.
+ *
+ * Copyright (C) 2024 Red Hat
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include "clutter/clutter-color-manager.h"
+
+#include "clutter/clutter-context.h"
+
+enum
+{
+  PROP_0,
+
+  PROP_CONTEXT,
+
+  N_PROPS
+};
+
+static GParamSpec *obj_props[N_PROPS];
+
+struct _ClutterColorManager
+{
+  GObject parent;
+
+  ClutterContext *context;
+};
+
+G_DEFINE_FINAL_TYPE (ClutterColorManager, clutter_color_manager, G_TYPE_OBJECT)
+
+static void
+clutter_color_manager_set_property (GObject      *object,
+                                    guint         prop_id,
+                                    const GValue *value,
+                                    GParamSpec   *pspec)
+{
+  ClutterColorManager *color_manager = CLUTTER_COLOR_MANAGER (object);
+
+  switch (prop_id)
+    {
+    case PROP_CONTEXT:
+      color_manager->context = g_value_get_object (value);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+clutter_color_manager_get_property (GObject    *object,
+                                    guint       prop_id,
+                                    GValue     *value,
+                                    GParamSpec *pspec)
+{
+  ClutterColorManager *color_manager = CLUTTER_COLOR_MANAGER (object);
+
+  switch (prop_id)
+    {
+    case PROP_CONTEXT:
+      g_value_set_object (value, color_manager->context);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+clutter_color_manager_class_init (ClutterColorManagerClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->set_property = clutter_color_manager_set_property;
+  object_class->get_property = clutter_color_manager_get_property;
+
+  /**
+   * ClutterColorManager:context:
+   *
+   * The associated ClutterContext.
+   */
+  obj_props[PROP_CONTEXT] =
+    g_param_spec_object ("context", NULL, NULL,
+                         CLUTTER_TYPE_CONTEXT,
+                         G_PARAM_READWRITE |
+                         G_PARAM_STATIC_STRINGS |
+                         G_PARAM_CONSTRUCT_ONLY);
+
+  g_object_class_install_properties (object_class, N_PROPS, obj_props);
+}
+
+static void
+clutter_color_manager_init (ClutterColorManager *color_manager)
+{
+}

clutter/clutter/clutter-color-manager.h

@@ -0,0 +1,34 @@
+/*
+ * Clutter.
+ *
+ * An OpenGL based 'interactive canvas' library.
+ *
+ * Copyright (C) 2024 Red Hat
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#pragma once
+
+#if !defined(__CLUTTER_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
+#error "Only <clutter/clutter.h> can be included directly."
+#endif
+
+#include "clutter/clutter-types.h"
+
+#define CLUTTER_TYPE_COLOR_MANAGER (clutter_color_manager_get_type ())
+CLUTTER_EXPORT
+G_DECLARE_FINAL_TYPE (ClutterColorManager, clutter_color_manager,
+                      CLUTTER, COLOR_MANAGER, GObject)

clutter/clutter/clutter-context.c

@@ -24,6 +24,7 @@
 
 #include "cally/cally.h"
 #include "clutter/clutter-backend-private.h"
+#include "clutter/clutter-color-manager.h"
 #include "clutter/clutter-debug.h"
 #include "clutter/clutter-main.h"
 #include "clutter/clutter-private.h"
@@ -80,6 +81,7 @@ typedef struct _ClutterContextPrivate
 {
   ClutterTextDirection text_direction;
 
+  ClutterColorManager *color_manager;
   ClutterPipelineCache *pipeline_cache;
 } ClutterContextPrivate;
 
@@ -92,6 +94,7 @@ clutter_context_dispose (GObject *object)
   ClutterContextPrivate *priv = clutter_context_get_instance_private (context);
 
   g_clear_object (&priv->pipeline_cache);
+  g_clear_object (&priv->color_manager);
   g_clear_pointer (&context->events_queue, g_async_queue_unref);
   g_clear_pointer (&context->backend, clutter_backend_destroy);
 
@@ -274,6 +277,9 @@ clutter_context_new (ClutterContextFlags         flags,
     g_async_queue_new_full ((GDestroyNotify) clutter_event_free);
   context->last_repaint_id = 1;
 
+  priv->color_manager = g_object_new (CLUTTER_TYPE_COLOR_MANAGER,
+                                      "context", context,
+                                      NULL);
   priv->pipeline_cache = g_object_new (CLUTTER_TYPE_PIPELINE_CACHE, NULL);
 
   if (!clutter_context_init_real (context, flags, error))

clutter/clutter/clutter-types.h

@@ -48,6 +48,7 @@ typedef struct _ClutterFrame                    ClutterFrame;
 typedef struct _ClutterFrameInfo                ClutterFrameInfo;
 typedef struct _ClutterLayoutMeta               ClutterLayoutMeta;
 typedef struct _ClutterActorMeta                ClutterActorMeta;
+typedef struct _ClutterColorManager             ClutterColorManager;
 typedef struct _ClutterLayoutManager            ClutterLayoutManager;
 typedef struct _ClutterActorIter                ClutterActorIter;
 typedef struct _ClutterPaintContext             ClutterPaintContext;

clutter/clutter/clutter.h

@@ -43,6 +43,7 @@
 #include "clutter/clutter-brightness-contrast-effect.h"
 #include "clutter/clutter-click-action.h"
 #include "clutter/clutter-clone.h"
+#include "clutter/clutter-color-manager.h"
 #include "clutter/clutter-color-state.h"
 #include "clutter/clutter-colorize-effect.h"
 #include "clutter/clutter-constraint.h"

clutter/clutter/meson.build

@@ -17,6 +17,7 @@ clutter_headers = [
   'clutter-brightness-contrast-effect.h',
   'clutter-click-action.h',
   'clutter-clone.h',
+  'clutter-color-manager.h',
   'clutter-color-state.h',
   'clutter-colorize-effect.h',
   'clutter-constraint.h',
@@ -101,6 +102,7 @@ clutter_sources = [
   'clutter-brightness-contrast-effect.c',
   'clutter-click-action.c',
   'clutter-clone.c',
+  'clutter-color-manager.c',
   'clutter-color-state.c',
   'clutter-colorize-effect.c',
   'clutter-constraint.c',