compositor: Require a context when creating a texture mipmap

avoids going through globals

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3989>

src/compositor/meta-shaped-texture.c

@@ -175,6 +175,20 @@ meta_shaped_texture_get_property (GObject    *object,
     }
 }
 
+static void
+meta_shaped_texture_constructed (GObject *object)
+{
+  MetaShapedTexture *stex = META_SHAPED_TEXTURE (object);
+  ClutterBackend *clutter_backend =
+    clutter_context_get_backend (stex->clutter_context);
+  CoglContext *cogl_context =
+    clutter_backend_get_cogl_context (clutter_backend);
+
+  G_OBJECT_CLASS (meta_shaped_texture_parent_class)->constructed (object);
+
+  stex->texture_mipmap = meta_texture_mipmap_new (cogl_context);
+}
+
 static void
 meta_shaped_texture_class_init (MetaShapedTextureClass *klass)
 {
@@ -183,6 +197,7 @@ meta_shaped_texture_class_init (MetaShapedTextureClass *klass)
   object_class->dispose = meta_shaped_texture_dispose;
   object_class->set_property = meta_shaped_texture_set_property;
   object_class->get_property = meta_shaped_texture_get_property;
+  object_class->constructed = meta_shaped_texture_constructed;
 
   signals[SIZE_CHANGED] = g_signal_new ("size-changed",
                                         G_TYPE_FROM_CLASS (klass),
@@ -215,7 +230,6 @@ invalidate_size (MetaShapedTexture *stex)
 static void
 meta_shaped_texture_init (MetaShapedTexture *stex)
 {
-  stex->texture_mipmap = meta_texture_mipmap_new ();
   stex->buffer_scale = 1;
   stex->texture = NULL;
   stex->mask_texture = NULL;

src/compositor/meta-texture-mipmap.c

@@ -36,6 +36,7 @@ struct _MetaTextureMipmap
   MetaMultiTexture *mipmap_texture;
   CoglPipeline *pipeline;
   CoglFramebuffer *fb;
+  CoglContext *cogl_context;
   gboolean invalid;
 };
 
@@ -48,11 +49,12 @@ struct _MetaTextureMipmap
  * Return value: the new texture mipmap handler. Free with meta_texture_mipmap_free()
  */
 MetaTextureMipmap *
-meta_texture_mipmap_new (void)
+meta_texture_mipmap_new (CoglContext *cogl_context)
 {
   MetaTextureMipmap *mipmap;
 
   mipmap = g_new0 (MetaTextureMipmap, 1);
+  mipmap->cogl_context = cogl_context;
 
   return mipmap;
 }
@@ -132,8 +134,6 @@ meta_texture_mipmap_clear (MetaTextureMipmap *mipmap)
 static void
 ensure_mipmap_texture (MetaTextureMipmap *mipmap)
 {
-  CoglContext *ctx =
-    clutter_backend_get_cogl_context (clutter_get_default_backend ());
   int width, height;
 
   /* Let's avoid spending any texture memory copying the base level texture
@@ -172,7 +172,7 @@ ensure_mipmap_texture (MetaTextureMipmap *mipmap)
 
       free_mipmaps (mipmap);
 
-      tex = cogl_texture_2d_new_with_size (ctx, width, height);
+      tex = cogl_texture_2d_new_with_size (mipmap->cogl_context, width, height);
       if (!tex)
         return;
 
@@ -212,7 +212,7 @@ ensure_mipmap_texture (MetaTextureMipmap *mipmap)
           CoglSnippet *fragment_globals_snippet;
           CoglSnippet *fragment_snippet;
 
-          mipmap->pipeline = cogl_pipeline_new (ctx);
+          mipmap->pipeline = cogl_pipeline_new (mipmap->cogl_context);
           cogl_pipeline_set_blend (mipmap->pipeline,
                                    "RGBA = ADD (SRC_COLOR, 0)",
                                    NULL);

src/compositor/meta-texture-mipmap.h

@@ -37,7 +37,7 @@ G_BEGIN_DECLS
 
 typedef struct _MetaTextureMipmap MetaTextureMipmap;
 
-MetaTextureMipmap *meta_texture_mipmap_new (void);
+MetaTextureMipmap *meta_texture_mipmap_new (CoglContext *cogl_context);
 
 void meta_texture_mipmap_free (MetaTextureMipmap *mipmap);