gsk: Introduce GskRenderNodeClass

This is modeled after GtkCssValueClass. So far it doesn't do anything.

gsk/gskrenderer.c

@@ -676,6 +676,11 @@ gsk_renderer_render (GskRenderer       *renderer,
   g_clear_pointer (&priv->root_node, gsk_render_node_unref);
 }
 
+static const GskRenderNodeClass GSK_CONTAINER_NODE_CLASS = {
+  GSK_CONTAINER_NODE,
+  "GskContainerNode"
+};
+
 /**
  * gsk_renderer_create_render_node:
  * @renderer: a #GskRenderer
@@ -691,7 +696,7 @@ gsk_renderer_create_render_node (GskRenderer *renderer)
 {
   g_return_val_if_fail (GSK_IS_RENDERER (renderer), NULL);
 
-  return gsk_render_node_new (GSK_CONTAINER_NODE);
+  return gsk_render_node_new (&GSK_CONTAINER_NODE_CLASS);
 }
 
 /*< private >

gsk/gskrendernode.c

@@ -86,20 +86,21 @@ gsk_render_node_finalize (GskRenderNode *self)
 
 /*< private >
  * gsk_render_node_new:
- * @type: type of the new node
+ * @node_class: class structure for this node
  *
  * Returns: (transfer full): the newly created #GskRenderNode
  */
 GskRenderNode *
-gsk_render_node_new (GskRenderNodeType type)
+gsk_render_node_new (const GskRenderNodeClass *node_class)
 {
   GskRenderNode *self;
   
-  g_return_val_if_fail (type != GSK_NOT_A_RENDER_NODE, NULL);
+  g_return_val_if_fail (node_class != NULL, NULL);
+  g_return_val_if_fail (node_class->node_type != GSK_NOT_A_RENDER_NODE, NULL);
 
   self = g_slice_new0 (GskRenderNode);
 
-  self->type = type;
+  self->node_class = node_class;
 
   self->ref_count = 1;
 
@@ -173,7 +174,7 @@ gsk_render_node_get_node_type (GskRenderNode *node)
 {
   g_return_val_if_fail (GSK_IS_RENDER_NODE (node), GSK_NOT_A_RENDER_NODE);
 
-  return node->type;
+  return node->node_class->node_type;
 }
 
 /**
@@ -393,8 +394,7 @@ GskRenderNode *
 gsk_render_node_append_child (GskRenderNode *node,
                               GskRenderNode *child)
 {
-  g_return_val_if_fail (GSK_IS_RENDER_NODE (node), NULL);
+  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_CONTAINER_NODE), NULL);
-  g_return_val_if_fail (node->type == GSK_CONTAINER_NODE, NULL);
   g_return_val_if_fail (GSK_IS_RENDER_NODE (child), node);
   g_return_val_if_fail (node->is_mutable, node);
 
@@ -494,9 +494,8 @@ void
 gsk_render_node_set_bounds (GskRenderNode         *node,
                             const graphene_rect_t *bounds)
 {
-  g_return_if_fail (GSK_IS_RENDER_NODE (node));
+  g_return_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_CONTAINER_NODE));
   g_return_if_fail (node->is_mutable);
-  g_return_if_fail (node->type == GSK_CONTAINER_NODE);
 
   if (bounds == NULL)
     graphene_rect_init_from_rect (&node->bounds, graphene_rect_zero ());

gsk/gskrendernodeimpl.c

@@ -24,11 +24,15 @@
 
 /*** GSK_TEXTURE_NODE ***/
 
+static const GskRenderNodeClass GSK_TEXTURE_NODE_CLASS = {
+  GSK_TEXTURE_NODE,
+  "GskTextureNode"
+};
+
 GskTexture *
 gsk_texture_node_get_texture (GskRenderNode *node)
 {
-  g_return_val_if_fail (GSK_IS_RENDER_NODE (node), 0);
+  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_TEXTURE_NODE), 0);
-  g_return_val_if_fail (node->type == GSK_TEXTURE_NODE, 0);
 
   return node->texture;
 }
@@ -54,7 +58,7 @@ gsk_texture_node_new (GskTexture            *texture,
   g_return_val_if_fail (GSK_IS_TEXTURE (texture), NULL);
   g_return_val_if_fail (bounds != NULL, NULL);
 
-  node = gsk_render_node_new (GSK_TEXTURE_NODE);
+  node = gsk_render_node_new (&GSK_TEXTURE_NODE_CLASS);
 
   node->texture = gsk_texture_ref (texture);
   graphene_rect_init_from_rect (&node->bounds, bounds);
@@ -64,6 +68,11 @@ gsk_texture_node_new (GskTexture            *texture,
 
 /*** GSK_CAIRO_NODE ***/
 
+static const GskRenderNodeClass GSK_CAIRO_NODE_CLASS = {
+  GSK_CAIRO_NODE,
+  "GskCairoNode"
+};
+
 /*< private >
  * gsk_cairo_node_get_surface:
  * @node: a #GskRenderNode
@@ -75,8 +84,7 @@ gsk_texture_node_new (GskTexture            *texture,
 cairo_surface_t *
 gsk_cairo_node_get_surface (GskRenderNode *node)
 {
-  g_return_val_if_fail (GSK_IS_RENDER_NODE (node), NULL);
+  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_CAIRO_NODE), NULL);
-  g_return_val_if_fail (node->type == GSK_CAIRO_NODE, NULL);
 
   return node->surface;
 }
@@ -100,7 +108,7 @@ gsk_cairo_node_new (const graphene_rect_t *bounds)
 
   g_return_val_if_fail (bounds != NULL, NULL);
 
-  node = gsk_render_node_new (GSK_CAIRO_NODE);
+  node = gsk_render_node_new (&GSK_CAIRO_NODE_CLASS);
 
   graphene_rect_init_from_rect (&node->bounds, bounds);
 
@@ -129,8 +137,7 @@ gsk_cairo_node_get_draw_context (GskRenderNode *node,
   int width, height;
   cairo_t *res;
 
-  g_return_val_if_fail (GSK_IS_RENDER_NODE (node), NULL);
+  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_CAIRO_NODE), NULL);
-  g_return_val_if_fail (node->type == GSK_CAIRO_NODE, NULL);
   g_return_val_if_fail (node->is_mutable, NULL);
   g_return_val_if_fail (renderer == NULL || GSK_IS_RENDERER (renderer), NULL);
 

gsk/gskrendernodeprivate.h

@@ -6,9 +6,13 @@
 
 G_BEGIN_DECLS
 
+typedef struct _GskRenderNodeClass GskRenderNodeClass;
+
+#define GSK_IS_RENDER_NODE_TYPE(node,type) (GSK_IS_RENDER_NODE (node) && (node)->node_class->node_type == (type))
+
 struct _GskRenderNode
 {
-  GskRenderNodeType type;
+  const GskRenderNodeClass *node_class;
 
   volatile int ref_count;
 
@@ -59,7 +63,13 @@ struct _GskRenderNode
   gboolean needs_world_matrix_update : 1;
 };
 
-GskRenderNode *gsk_render_node_new (GskRenderNodeType type);
+struct _GskRenderNodeClass
+{
+  GskRenderNodeType node_type;
+  const char *type_name;
+};
+
+GskRenderNode *gsk_render_node_new (const GskRenderNodeClass *node_class);
 
 void gsk_render_node_make_immutable (GskRenderNode *node);