clutter: Remove 'features'

There are no 'features' left, the last one, GLSL shader support, was
moved to Cogl.

This also move the Cogl context creation to a more sensible place, as it
was hidden away in the feature initialization.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2015>

clutter/clutter/clutter-backend-private.h

@@ -71,7 +71,6 @@ struct _ClutterBackendClass
   ClutterStageWindow *  (* create_stage)       (ClutterBackend  *backend,
                                                 ClutterStage    *wrapper,
                                                 GError         **error);
-  void                  (* init_features)      (ClutterBackend  *backend);
   CoglRenderer *        (* get_renderer)       (ClutterBackend  *backend,
                                                 GError         **error);
   CoglDisplay *         (* get_display)        (ClutterBackend  *backend,

clutter/clutter/clutter-enums.h

@@ -903,20 +903,6 @@ typedef enum /*< prefix=CLUTTER_SCROLL >*/
   CLUTTER_SCROLL_SMOOTH
 } ClutterScrollDirection;
 
-/**
- * ClutterFeatureFlags:
- * @CLUTTER_FEATURE_SHADERS_GLSL: Set if the backend supports GLSL shaders.
- *
- * Runtime flags indicating specific features available via Clutter window
- * system and graphics backend.
- *
- * Since: 0.4
- */
-typedef enum
-{
-  CLUTTER_FEATURE_SHADERS_GLSL           = (1 << 9),
-} ClutterFeatureFlags;
-
 /**
  * ClutterFlowOrientation:
  * @CLUTTER_FLOW_HORIZONTAL: Arrange the children of the flow layout

clutter/clutter/clutter-feature.c

@@ -1,142 +0,0 @@
-/*
- * Clutter.
- *
- * An OpenGL based 'interactive canvas' library.
- *
- * Authored By Matthew Allum  <mallum@openedhand.com>
- *
- * Copyright (C) 2006 OpenedHand
- *
- * 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/>.
- *
- *
- */
-
-/**
- * SECTION:clutter-feature
- * @short_description: Run-time detection of Clutter features
- *
- * Parts of Clutter depend on the underlying platform, including the
- * capabilities of the backend used and the OpenGL features exposed through the
- * Clutter and COGL API.
- *
- * It is possible to ask whether Clutter has support for specific features at
- * run-time.
- */
-
-#include "clutter-build-config.h"
-
-#include <stdlib.h>
-#include <string.h>
-#include <sys/types.h>
-
-#include "clutter-backend-private.h"
-#include "clutter-feature.h"
-#include "clutter-main.h"
-#include "clutter-private.h"
-#include "clutter-debug.h"
-
-#include "cogl/cogl.h"
-
-typedef struct ClutterFeatures
-{
-  ClutterFeatureFlags flags;
-  guint               features_set : 1;
-} ClutterFeatures;
-
-static ClutterFeatures* __features = NULL;
-
-static ClutterFeatureFlags
-clutter_features_from_cogl (void)
-{
-  ClutterFeatureFlags clutter_flags = 0;
-  
-  clutter_flags |= CLUTTER_FEATURE_SHADERS_GLSL;
-  
-  return clutter_flags;
-}
-
-gboolean
-clutter_feature_init (ClutterMainContext  *context,
-                      GError             **error)
-{
-  CLUTTER_NOTE (MISC, "checking features");
-
-  if (!__features)
-    {
-      CLUTTER_NOTE (MISC, "allocating features data");
-      __features = g_new0 (ClutterFeatures, 1);
-      __features->features_set = FALSE; /* don't rely on zero-ing */
-    }
-
-  if (__features->features_set)
-    return TRUE;
-
-  /* makes sure we have a GL context; if we have, this is a no-op */
-  if (!_clutter_backend_create_context (context->backend, error))
-    return FALSE;
-
-  __features->flags = clutter_features_from_cogl ();
-
-  __features->features_set = TRUE;
-
-  CLUTTER_NOTE (MISC, "features checked");
-
-  return TRUE;
-}
-
-/**
- * clutter_feature_available:
- * @feature: a #ClutterFeatureFlags
- *
- * Checks whether @feature is available.  @feature can be a logical
- * OR of #ClutterFeatureFlags.
- *
- * Return value: %TRUE if a feature is available
- *
- * Since: 0.2
- */
-gboolean
-clutter_feature_available (ClutterFeatureFlags feature)
-{
-  if (G_UNLIKELY (!__features))
-    {
-      g_critical ("Unable to check features. Have you initialized Clutter?");
-      return FALSE;
-    }
-
-  return (__features->flags & feature);
-}
-
-/**
- * clutter_feature_get_all:
- *
- * Returns all the supported features.
- *
- * Return value: a logical OR of all the supported features.
- *
- * Since: 0.2
- */
-ClutterFeatureFlags
-clutter_feature_get_all (void)
-{
-  if (G_UNLIKELY (!__features))
-    {
-      g_critical ("Unable to check features. Have you initialized Clutter?");
-      return FALSE;
-    }
-
-  return __features->flags;
-}
-

clutter/clutter/clutter-feature.h

@@ -1,42 +0,0 @@
-/*
- * Clutter.
- *
- * An OpenGL based 'interactive canvas' library.
- *
- * Authored By Matthew Allum  <mallum@openedhand.com>
- *
- * Copyright (C) 2006 OpenedHand
- *
- * 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/>.
- */
-
-#ifndef __CLUTTER_FEATURE_H__
-#define __CLUTTER_FEATURE_H__
-
-#if !defined(__CLUTTER_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
-#error "Only <clutter/clutter.h> can be included directly."
-#endif
-
-#include <clutter/clutter-types.h>
-
-G_BEGIN_DECLS
-
-CLUTTER_EXPORT
-gboolean            clutter_feature_available       (ClutterFeatureFlags feature);
-CLUTTER_EXPORT
-ClutterFeatureFlags clutter_feature_get_all         (void);
-
-G_END_DECLS
-
-#endif /* __CLUTTER_FEATURE_H__ */

clutter/clutter/clutter-main.c

@@ -55,7 +55,6 @@
 #include "clutter-backend-private.h"
 #include "clutter-debug.h"
 #include "clutter-event-private.h"
-#include "clutter-feature.h"
 #include "clutter-input-device-private.h"
 #include "clutter-input-pointer-a11y-private.h"
 #include "clutter-graphene.h"
@@ -522,10 +521,7 @@ clutter_init_real (ClutterMainContext  *clutter_context,
   if (clutter_paint_debug_flags & CLUTTER_DEBUG_PAINT_DAMAGE_REGION)
     g_message ("Enabling damaged region");
 
-  /* this will take care of initializing Cogl's state and
+  if (!_clutter_backend_create_context (clutter_context->backend, error))
-   * query the GL machinery for features
-   */
-  if (!clutter_feature_init (clutter_context, error))
     return FALSE;
 
   clutter_text_direction = clutter_get_text_direction ();

clutter/clutter/clutter-private.h

@@ -34,7 +34,6 @@
 #include "clutter-backend.h"
 #include "clutter-effect.h"
 #include "clutter-event.h"
-#include "clutter-feature.h"
 #include "clutter-id-pool.h"
 #include "clutter-layout-manager.h"
 #include "clutter-settings.h"
@@ -167,9 +166,6 @@ CLUTTER_EXPORT
 gboolean                _clutter_context_is_initialized                 (void);
 gboolean                _clutter_context_get_show_fps                   (void);
 
-gboolean clutter_feature_init (ClutterMainContext  *clutter_context,
-                               GError             **error);
-
 /* Diagnostic mode */
 gboolean        _clutter_diagnostic_enabled     (void);
 void            _clutter_diagnostic_message     (const char *fmt, ...) G_GNUC_PRINTF (1, 2);

clutter/clutter/clutter-shader-effect.c

@@ -119,7 +119,6 @@
 
 #include "clutter-debug.h"
 #include "clutter-enum-types.h"
-#include "clutter-feature.h"
 #include "clutter-private.h"
 #include "clutter-shader-types.h"
 

clutter/clutter/clutter.h

@@ -59,7 +59,6 @@
 #include "clutter-enums.h"
 #include "clutter-enum-types.h"
 #include "clutter-event.h"
-#include "clutter-feature.h"
 #include "clutter-fixed-layout.h"
 #include "clutter-flow-layout.h"
 #include "clutter-frame-clock.h"

clutter/clutter/meson.build

@@ -33,7 +33,6 @@ clutter_headers = [
   'clutter-effect.h',
   'clutter-enums.h',
   'clutter-event.h',
-  'clutter-feature.h',
   'clutter-fixed-layout.h',
   'clutter-flow-layout.h',
   'clutter-frame-clock.h',
@@ -123,7 +122,6 @@ clutter_sources = [
   'clutter-desaturate-effect.c',
   'clutter-effect.c',
   'clutter-event.c',
-  'clutter-feature.c',
   'clutter-fixed-layout.c',
   'clutter-flatten-effect.c',
   'clutter-flow-layout.c',