[gtk+/wip/ebassi/gsk-renderer: 87/103] gsk: Tie render nodes to renderers

[Emmanuele Bassi <ebassi src gnome org>]

commit 3f4d8c65d134dab6211ca2111a1f644078eb93d5
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Wed Jul 27 16:23:44 2016 +0100

    gsk: Tie render nodes to renderers
    
    Render nodes need access to rendering information like scaling factors.
    If we keep render nodes separate from renderers until we submit a nodes
    tree for rendering we're going to have to duplicate all that information
    in a way that makes the API more complicated and fuzzier on its
    semantics.
    
    By having GskRenderer create GskRenderNode instances we can tie nodes
    and renderers together; since higher layers will also have access to
    the renderer instance, this does not add any burden to callers.
    
    Additionally, if memory measurements indicate that we are spending too
    much time in the allocation of new render nodes, we can now easily
    implement a free-list or a renderer-specific allocator without breaking
    the API.

 gsk/gskrenderer.c          |   19 +++++++++++++++++++
 gsk/gskrenderer.h          |    4 ++++
 gsk/gskrendernode.c        |   15 +++++++++------
 gsk/gskrendernode.h        |    2 --
 gsk/gskrendernodeprivate.h |    6 ++++++
 gtk/gtkwidget.c            |    4 ++--
 gtk/gtkwindow.c            |    2 +-
 7 files changed, 41 insertions(+), 11 deletions(-)
---
diff --git a/gsk/gskrenderer.c b/gsk/gskrenderer.c
index 8a9068f..a1b9e3f 100644
--- a/gsk/gskrenderer.c
+++ b/gsk/gskrenderer.c
@@ -921,6 +921,7 @@ gsk_renderer_render (GskRenderer       *renderer,
   g_return_if_fail (GDK_IS_DRAWING_CONTEXT (context));
   g_return_if_fail (priv->drawing_context == NULL);
   g_return_if_fail (priv->root_node == NULL);
+  g_return_if_fail (root->renderer == renderer);
 
   priv->drawing_context = g_object_ref (context);
   priv->root_node = gsk_render_node_ref (root);
@@ -1035,6 +1036,24 @@ gsk_renderer_get_use_alpha (GskRenderer *renderer)
 }
 
 /**
+ * gsk_renderer_create_render_node:
+ * @renderer: a #GskRenderer
+ *
+ * Creates a new #GskRenderNode instance tied to the given @renderer.
+ *
+ * Returns: (transfer full): the new #GskRenderNode
+ *
+ * Since: 3.22
+ */
+GskRenderNode *
+gsk_renderer_create_render_node (GskRenderer *renderer)
+{
+  g_return_val_if_fail (GSK_IS_RENDERER (renderer), NULL);
+
+  return gsk_render_node_new (renderer);
+}
+
+/**
  * gsk_renderer_get_for_display:
  * @display: a #GdkDisplay
  *
diff --git a/gsk/gskrenderer.h b/gsk/gskrenderer.h
index ec1d3aa..7928917 100644
--- a/gsk/gskrenderer.h
+++ b/gsk/gskrenderer.h
@@ -96,6 +96,10 @@ GDK_AVAILABLE_IN_3_22
 gboolean                gsk_renderer_realize                    (GskRenderer             *renderer);
 GDK_AVAILABLE_IN_3_22
 void                    gsk_renderer_unrealize                  (GskRenderer             *renderer);
+
+GDK_AVAILABLE_IN_3_22
+GskRenderNode *         gsk_renderer_create_render_node         (GskRenderer             *renderer);
+
 GDK_AVAILABLE_IN_3_22
 void                    gsk_renderer_render                     (GskRenderer             *renderer,
                                                                  GskRenderNode           *root,
diff --git a/gsk/gskrendernode.c b/gsk/gskrendernode.c
index 93bd2dd..70aeb4c 100644
--- a/gsk/gskrendernode.c
+++ b/gsk/gskrendernode.c
@@ -233,19 +233,22 @@ gsk_render_node_get_type (void)
   return gsk_render_node_type__volatile;
 }
 
-/**
+/*< private >
  * gsk_render_node_new:
+ * @renderer: a #GskRenderer
  *
- * Creates a new #GskRenderNode, to be used with #GskRenderer.
+ * Creates a new #GskRenderNode, to be used with a #GskRenderer.
  *
  * Returns: (transfer full): the newly created #GskRenderNode
- *
- * Since: 3.22
  */
 GskRenderNode *
-gsk_render_node_new (void)
+gsk_render_node_new (GskRenderer *renderer)
 {
-  return (GskRenderNode *) g_type_create_instance (GSK_TYPE_RENDER_NODE);
+  GskRenderNode *res = (GskRenderNode *) g_type_create_instance (GSK_TYPE_RENDER_NODE);
+
+  res->renderer = renderer;
+
+  return res;
 }
 
 /**
diff --git a/gsk/gskrendernode.h b/gsk/gskrendernode.h
index a4709ff..8cbd243 100644
--- a/gsk/gskrendernode.h
+++ b/gsk/gskrendernode.h
@@ -39,8 +39,6 @@ GDK_AVAILABLE_IN_3_22
 GType gsk_render_node_get_type (void) G_GNUC_CONST;
 
 GDK_AVAILABLE_IN_3_22
-GskRenderNode *         gsk_render_node_new                     (void);
-GDK_AVAILABLE_IN_3_22
 GskRenderNode *         gsk_render_node_ref                     (GskRenderNode *node);
 GDK_AVAILABLE_IN_3_22
 void                    gsk_render_node_unref                   (GskRenderNode *node);
diff --git a/gsk/gskrendernodeprivate.h b/gsk/gskrendernodeprivate.h
index 9893f96..8e6bca8 100644
--- a/gsk/gskrendernodeprivate.h
+++ b/gsk/gskrendernodeprivate.h
@@ -2,6 +2,7 @@
 #define __GSK_RENDER_NODE_PRIVATE_H__
 
 #include "gskrendernode.h"
+#include "gskrenderer.h"
 #include <cairo.h>
 
 G_BEGIN_DECLS
@@ -16,6 +17,9 @@ struct _GskRenderNode
 
   volatile int ref_count;
 
+  /* Back pointer to the renderer that created the node */
+  GskRenderer *renderer;
+
   /* The graph */
   GskRenderNode *parent;
   GskRenderNode *first_child;
@@ -68,6 +72,8 @@ struct _GskRenderNodeClass
   void (* finalize) (GskRenderNode *node);
 };
 
+GskRenderNode *gsk_render_node_new (GskRenderer *renderer);
+
 void gsk_render_node_make_immutable (GskRenderNode *node);
 
 void gsk_render_node_get_bounds (GskRenderNode   *node,
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index 1320a68..307e9ec 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -17497,7 +17497,7 @@ gtk_widget_get_render_node (GtkWidget   *widget,
       GskRenderNode *tmp;
       cairo_t *cr;
 
-      tmp = gsk_render_node_new ();
+      tmp = gsk_renderer_create_render_node (renderer);
       gsk_render_node_set_name (tmp, "Draw Fallback");
       gsk_render_node_set_bounds (tmp, &bounds);
       gsk_render_node_set_transform (tmp, &m);
@@ -17520,7 +17520,7 @@ gtk_widget_get_render_node (GtkWidget   *widget,
           gboolean result;
           cairo_t *cr;
 
-          tmp = gsk_render_node_new ();
+          tmp = gsk_renderer_create_render_node (renderer);
           gsk_render_node_set_name (tmp, "Draw Signal Handler");
           gsk_render_node_set_bounds (tmp, &bounds);
           gsk_render_node_set_transform (tmp, &m);
diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index 0a2963a..5ccc5a3 100644
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -10161,7 +10161,7 @@ gtk_window_get_render_node (GtkWidget   *widget,
   graphene_rect_init (&bounds, allocation.x, allocation.y, allocation.width, allocation.height);
   graphene_matrix_init_translate (&m, graphene_point3d_init (&p, allocation.x, allocation.y, 0.));
 
-  node = gsk_render_node_new ();
+  node = gsk_renderer_create_render_node (renderer);
   gsk_render_node_set_name (node, "Window Decoration");
   gsk_render_node_set_bounds (node, &bounds);
   gsk_render_node_set_transform (node, &m);