gsk: Remove offset nodes

They were a neat idea while they lasted. But now, it's time for
categorized transform nodes, where matrices with
GSK_MATRIX_CATEGORY_2D_TRANSLATE are the exact replacement.

Renderers have not been adapted for this purpose, so they (continue to)
run slow paths.

8 files changed, 18 insertions, 289 deletions

diff --git a/gsk/gl/gskglrenderer.c b/gsk/gl/gskglrenderer.c
index 6e7abbc3e1..d8444a9613 100644
--- a/gsk/gl/gskglrenderer.c
+++ b/gsk/gl/gskglrenderer.c
@@ -77,11 +77,6 @@ print_render_node_tree (GskRenderNode *root, int level)
           print_render_node_tree (gsk_container_node_get_child (root, i), level + 1);
         break;
 
-      case GSK_OFFSET_NODE:
-        g_print ("%*s Offset\n", level * INDENT, " ");
-        print_render_node_tree (gsk_offset_node_get_child (root), level + 1);
-        break;
-
       case GSK_TRANSFORM_NODE:
         g_print ("%*s Transform\n", level * INDENT, " ");
         print_render_node_tree (gsk_transform_node_get_child (root), level + 1);
@@ -766,20 +761,6 @@ render_texture_node (GskGLRenderer       *self,
 }
 
 static inline void
-render_offset_node (GskGLRenderer   *self,
-                    GskRenderNode   *node,
-                    RenderOpBuilder *builder)
-{
-  GskRenderNode *child = gsk_offset_node_get_child (node);
-  const float dx = gsk_offset_node_get_x_offset (node);
-  const float dy = gsk_offset_node_get_y_offset (node);
-
-  ops_offset (builder, dx, dy);
-  gsk_gl_renderer_add_render_ops (self, child, builder);
-  ops_offset (builder, - dx, - dy);
-}
-
-static inline void
 render_transform_node (GskGLRenderer   *self,
                        GskRenderNode   *node,
                        RenderOpBuilder *builder)
@@ -2348,10 +2329,6 @@ gsk_gl_renderer_add_render_ops (GskGLRenderer   *self,
       render_texture_node (self, node, builder);
     break;
 
-    case GSK_OFFSET_NODE:
-      render_offset_node (self, node, builder);
-    break;
-
     case GSK_TRANSFORM_NODE:
       render_transform_node (self, node, builder);
     break;
diff --git a/gsk/gskbroadwayrenderer.c b/gsk/gskbroadwayrenderer.c
index d402cdd831..fc4507f62b 100644
--- a/gsk/gskbroadwayrenderer.c
+++ b/gsk/gskbroadwayrenderer.c
@@ -580,15 +580,6 @@ gsk_broadway_renderer_add_node (GskRenderer *renderer,
 
       /* Bin nodes */
 
-    case GSK_OFFSET_NODE:
-      {
-        gsk_broadway_renderer_add_node (renderer, nodes, node_textures,
-                                        gsk_offset_node_get_child (node),
-                                        offset_x - gsk_offset_node_get_x_offset (node),
-                                        offset_y - gsk_offset_node_get_y_offset (node));
-      }
-      return;
-
     case GSK_SHADOW_NODE:
       {
         gsize i, n_shadows = gsk_shadow_node_get_n_shadows (node);
diff --git a/gsk/gskenums.h b/gsk/gskenums.h
index 4c17675ef3..795a8ed37c 100644
--- a/gsk/gskenums.h
+++ b/gsk/gskenums.h
@@ -45,7 +45,6 @@
  * @GSK_CROSS_FADE_NODE: A node that cross-fades between two children
  * @GSK_TEXT_NODE: A node containing a glyph string
  * @GSK_BLUR_NODE: A node that applies a blur
- * @GSK_OFFSET_NODE: A node that renders its child after applying a 2D translation
  *
  * The type of a node determines what the node is rendering.
  **/
@@ -71,7 +70,6 @@ typedef enum {
   GSK_CROSS_FADE_NODE,
   GSK_TEXT_NODE,
   GSK_BLUR_NODE,
-  GSK_OFFSET_NODE,
   GSK_DEBUG_NODE
 } GskRenderNodeType;
 
diff --git a/gsk/gskrendernode.h b/gsk/gskrendernode.h
index 5abcf951fe..3099569471 100644
--- a/gsk/gskrendernode.h
+++ b/gsk/gskrendernode.h
@@ -204,17 +204,6 @@ const graphene_matrix_t *
                         gsk_transform_node_peek_transform       (GskRenderNode            *node);
 
 GDK_AVAILABLE_IN_ALL
-GskRenderNode *         gsk_offset_node_new                     (GskRenderNode            *child,
-                                                                 float                     x_offset,
-                                                                 float                     y_offset);
-GDK_AVAILABLE_IN_ALL
-GskRenderNode *         gsk_offset_node_get_child               (GskRenderNode            *node);
-GDK_AVAILABLE_IN_ALL
-float                   gsk_offset_node_get_x_offset            (GskRenderNode            *node);
-GDK_AVAILABLE_IN_ALL
-float                   gsk_offset_node_get_y_offset            (GskRenderNode            *node);
-
-GDK_AVAILABLE_IN_ALL
 GskRenderNode *         gsk_opacity_node_new                    (GskRenderNode            *child,
                                                                  double                    opacity);
 GDK_AVAILABLE_IN_ALL
diff --git a/gsk/gskrendernodeimpl.c b/gsk/gskrendernodeimpl.c
index 34dd509d1f..65c8e33332 100644
--- a/gsk/gskrendernodeimpl.c
+++ b/gsk/gskrendernodeimpl.c
@@ -2590,206 +2590,6 @@ gsk_transform_node_get_category (GskRenderNode *node)
   return self->category;
 }
 
-/*** GSK_OFFSET_NODE ***/
-
-typedef struct _GskOffsetNode GskOffsetNode;
-
-struct _GskOffsetNode
-{
-  GskRenderNode render_node;
-
-  GskRenderNode *child;
-  float x_offset;
-  float y_offset;
-};
-
-static void
-gsk_offset_node_finalize (GskRenderNode *node)
-{
-  GskOffsetNode *self = (GskOffsetNode *) node;
-
-  gsk_render_node_unref (self->child);
-}
-
-static void
-gsk_offset_node_draw (GskRenderNode *node,
-                      cairo_t       *cr)
-{
-  GskOffsetNode *self = (GskOffsetNode *) node;
-
-  cairo_translate (cr, self->x_offset, self->y_offset);
-  gsk_render_node_draw (self->child, cr);
-}
-
-static gboolean
-gsk_offset_node_can_diff (GskRenderNode *node1,
-                          GskRenderNode *node2)
-{
-  GskOffsetNode *self1 = (GskOffsetNode *) node1;
-  GskOffsetNode *self2 = (GskOffsetNode *) node2;
-
-  return self1->x_offset == self2->x_offset
-      && self1->y_offset == self2->y_offset
-      && gsk_render_node_can_diff (self1->child, self2->child);
-}
-
-static void
-gsk_offset_node_diff (GskRenderNode  *node1,
-                      GskRenderNode  *node2,
-                      cairo_region_t *region)
-{
-  GskOffsetNode *self1 = (GskOffsetNode *) node1;
-  GskOffsetNode *self2 = (GskOffsetNode *) node2;
-
-  if (self1->x_offset == self2->x_offset &&
-      self1->y_offset == self2->y_offset)
-    {
-      cairo_region_t *sub;
-
-      if (self1->child == self2->child)
-        return;
-
-      sub = cairo_region_create ();
-      gsk_render_node_diff (self1->child, self2->child, sub);
-      cairo_region_translate (sub, self1->x_offset, self1->y_offset);
-      cairo_region_union (region, sub);
-      cairo_region_destroy (sub);
-    }
-  else
-    {
-      gsk_render_node_diff_impossible (node1, node2, region);
-    }
-}
-
-#define GSK_OFFSET_NODE_VARIANT_TYPE "(dduv)"
-
-static GVariant *
-gsk_offset_node_serialize (GskRenderNode *node)
-{
-  GskOffsetNode *self = (GskOffsetNode *) node;
-
-  return g_variant_new (GSK_OFFSET_NODE_VARIANT_TYPE,
-                        self->x_offset,
-                        self->y_offset,
-                        (guint32) gsk_render_node_get_node_type (self->child),
-                        gsk_render_node_serialize_node (self->child));
-}
-
-static GskRenderNode *
-gsk_offset_node_deserialize (GVariant  *variant,
-                             GError   **error)
-{
-  double x_offset, y_offset;
-  guint32 child_type;
-  GVariant *child_variant;
-  GskRenderNode *result, *child;
-
-  if (!check_variant_type (variant, GSK_OFFSET_NODE_VARIANT_TYPE, error))
-    return NULL;
-
-  g_variant_get (variant, GSK_OFFSET_NODE_VARIANT_TYPE,
-                 &x_offset, &y_offset,
-                 &child_type, &child_variant);
-
-  child = gsk_render_node_deserialize_node (child_type, child_variant, error);
-  g_variant_unref (child_variant);
-
-  if (child == NULL)
-    return NULL;
-
-  result = gsk_offset_node_new (child, x_offset, y_offset);
-
-  gsk_render_node_unref (child);
-
-  return result;
-}
-
-static const GskRenderNodeClass GSK_OFFSET_NODE_CLASS = {
-  GSK_OFFSET_NODE,
-  sizeof (GskOffsetNode),
-  "GskOffsetNode",
-  gsk_offset_node_finalize,
-  gsk_offset_node_draw,
-  gsk_offset_node_can_diff,
-  gsk_offset_node_diff,
-  gsk_offset_node_serialize,
-  gsk_offset_node_deserialize
-};
-
-/**
- * gsk_offset_node_new:
- * @child: The node to offset
- * @x_offset: The x offset to apply
- * @y_offset: The y offset to apply
- *
- * Creates a #GskRenderNode that will offset the given @child
- * with the given @x_offset and @y_offset.
- *
- * This is a common special case of the matrix transform
- * achieved by gsk_transform_node_new().
- *
- * Returns: A new #GskRenderNode
- */
-GskRenderNode *
-gsk_offset_node_new (GskRenderNode *child,
-                     float          x_offset,
-                     float          y_offset)
-{
-  GskOffsetNode *self;
-
-  g_return_val_if_fail (GSK_IS_RENDER_NODE (child), NULL);
-
-  self = (GskOffsetNode *) gsk_render_node_new (&GSK_OFFSET_NODE_CLASS, 0);
-
-  self->child = gsk_render_node_ref (child);
-  self->x_offset = x_offset;
-  self->y_offset = y_offset;
-
-  graphene_rect_offset_r (&child->bounds,
-                          x_offset, y_offset,
-                          &self->render_node.bounds);
-
-  return &self->render_node;
-}
-
-/**
- * gsk_offset_node_get_child:
- * @node: a offset @GskRenderNode
- *
- * Gets the child node that is getting offset by the given @node.
- *
- * Returns: (transfer none): The child that is getting offset
- **/
-GskRenderNode *
-gsk_offset_node_get_child (GskRenderNode *node)
-{
-  GskOffsetNode *self = (GskOffsetNode *) node;
-
-  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_OFFSET_NODE), NULL);
-
-  return self->child;
-}
-
-float
-gsk_offset_node_get_x_offset (GskRenderNode *node)
-{
-  GskOffsetNode *self = (GskOffsetNode *) node;
-
-  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_OFFSET_NODE), 0.0);
-
-  return self->x_offset;
-}
-
-float
-gsk_offset_node_get_y_offset (GskRenderNode *node)
-{
-  GskOffsetNode *self = (GskOffsetNode *) node;
-
-  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_OFFSET_NODE), 0.0);
-
-  return self->y_offset;
-}
-
 /*** GSK_DEBUG_NODE ***/
 
 typedef struct _GskDebugNode GskDebugNode;
@@ -5320,7 +5120,7 @@ static const GskRenderNodeClass *klasses[] = {
   [GSK_CROSS_FADE_NODE] = &GSK_CROSS_FADE_NODE_CLASS,
   [GSK_TEXT_NODE] = &GSK_TEXT_NODE_CLASS,
   [GSK_BLUR_NODE] = &GSK_BLUR_NODE_CLASS,
-  [GSK_OFFSET_NODE] = &GSK_OFFSET_NODE_CLASS
+  [GSK_DEBUG_NODE] = &GSK_DEBUG_NODE_CLASS
 };
 
 GskRenderNode *
diff --git a/gsk/vulkan/gskvulkanrenderpass.c b/gsk/vulkan/gskvulkanrenderpass.c
index fa3d10ada6..4307340e7e 100644
--- a/gsk/vulkan/gskvulkanrenderpass.c
+++ b/gsk/vulkan/gskvulkanrenderpass.c
@@ -549,7 +549,6 @@ gsk_vulkan_render_pass_add_node (GskVulkanRenderPass           *self,
       gsk_vulkan_render_pass_add_node (self, render, constants, gsk_debug_node_get_child (node));
       return;
 
-    case GSK_OFFSET_NODE:
     case GSK_TRANSFORM_NODE:
       {
         graphene_matrix_t transform, mv;
@@ -560,21 +559,8 @@ gsk_vulkan_render_pass_add_node (GskVulkanRenderPass           *self,
           FALLBACK ("Transform nodes can't deal with clip type %u\n", clip->type);
 #endif
 
-        if (gsk_render_node_get_node_type (node) == GSK_TRANSFORM_NODE)
-          {
-            child = gsk_transform_node_get_child (node);
-            graphene_matrix_init_from_matrix (&transform, gsk_transform_node_peek_transform (node));
-          }
-        else
-          {
-            child = gsk_offset_node_get_child (node);
-            graphene_matrix_init_translate (&transform,
-                                            &GRAPHENE_POINT3D_INIT(
-                                                gsk_offset_node_get_x_offset (node),
-                                                gsk_offset_node_get_y_offset (node),
-                                                0.0
-                                            ));
-          }
+        child = gsk_transform_node_get_child (node);
+        graphene_matrix_init_from_matrix (&transform, gsk_transform_node_peek_transform (node));
         graphene_matrix_init_from_matrix (&mv, &self->mv);
         graphene_matrix_multiply (&transform, &mv, &self->mv);
         if (!gsk_vulkan_push_constants_transform (&op.constants.constants, constants, &transform, &child->bounds))
diff --git a/gtk/gtksnapshot.c b/gtk/gtksnapshot.c
index 2d31929d8a..8a85755dd5 100644
--- a/gtk/gtksnapshot.c
+++ b/gtk/gtksnapshot.c
@@ -349,8 +349,10 @@ gtk_snapshot_collect_offset (GtkSnapshot       *snapshot,
                              GskRenderNode    **nodes,
                              guint              n_nodes)
 {
-  GskRenderNode *node, *offset_node;
+  GskRenderNode *node, *result;
   GtkSnapshotState  *previous_state;
+  graphene_matrix_t matrix;
+  GskMatrixCategory category;
 
   node = gtk_snapshot_collect_default (snapshot, state, nodes, n_nodes);
   if (node == NULL)
@@ -361,25 +363,24 @@ gtk_snapshot_collect_offset (GtkSnapshot       *snapshot,
       previous_state->translate_y == 0.0)
     return node;
 
-  if (gsk_render_node_get_node_type (node) == GSK_OFFSET_NODE)
-    {
-      const float dx = previous_state->translate_x;
-      const float dy = previous_state->translate_y;
+  graphene_matrix_init_translate (&matrix,
+                                  &GRAPHENE_POINT3D_INIT (previous_state->translate_x,
+                                                          previous_state->translate_y,
+                                                          0));
+  category = GSK_MATRIX_CATEGORY_2D_TRANSLATE;
 
-      offset_node = gsk_offset_node_new (gsk_offset_node_get_child (node),
-                                         gsk_offset_node_get_x_offset (node) + dx,
-                                         gsk_offset_node_get_y_offset (node) + dy);
-    }
-  else
+  if (gsk_render_node_get_node_type (node) == GSK_TRANSFORM_NODE)
     {
-      offset_node = gsk_offset_node_new (node,
-                                         previous_state->translate_x,
-                                         previous_state->translate_y);
+      node = gsk_render_node_ref (gsk_transform_node_get_child (node));
+      graphene_matrix_multiply (&matrix, gsk_transform_node_peek_transform (node), &matrix);
+      category = MIN (category, gsk_transform_node_get_category (node));
     }
+  
+  result = gsk_transform_node_new_with_category (node, &matrix, category);
 
   gsk_render_node_unref (node);
 
-  return offset_node;
+  return result;
 }
 
 static void
diff --git a/gtk/inspector/recorder.c b/gtk/inspector/recorder.c
index 0a56aefb8a..7230b6bd74 100644
--- a/gtk/inspector/recorder.c
+++ b/gtk/inspector/recorder.c
@@ -118,9 +118,6 @@ create_list_model_for_render_node (GskRenderNode *node)
       /* no children */
       return NULL;
 
-    case GSK_OFFSET_NODE:
-      return create_render_node_list_model ((GskRenderNode *[1]) { gsk_offset_node_get_child (node) }, 1);
-
     case GSK_TRANSFORM_NODE:
       return create_render_node_list_model ((GskRenderNode *[1]) { gsk_transform_node_get_child (node) }, 1);
 
@@ -230,8 +227,6 @@ node_type_name (GskRenderNodeType type)
       return "Outset Shadow";
     case GSK_TRANSFORM_NODE:
       return "Transform";
-    case GSK_OFFSET_NODE:
-      return "Offset";
     case GSK_OPACITY_NODE:
       return "Opacity";
     case GSK_COLOR_MATRIX_NODE:
@@ -283,9 +278,6 @@ node_name (GskRenderNode *node)
     case GSK_BLUR_NODE:
       return g_strdup (node_type_name (gsk_render_node_get_node_type (node)));
 
-    case GSK_OFFSET_NODE:
-      return g_strdup_printf ("Offset %g, %g", gsk_offset_node_get_x_offset (node), gsk_offset_node_get_y_offset (node));
-
     case GSK_DEBUG_NODE:
       return g_strdup (gsk_debug_node_get_message (node));
 
@@ -894,11 +886,6 @@ populate_render_node_properties (GtkListStore  *store,
       }
       break;
 
-    case GSK_OFFSET_NODE:
-      add_float_row (store, "x offset", gsk_offset_node_get_x_offset (node));
-      add_float_row (store, "y offset", gsk_offset_node_get_y_offset (node));
-      break;
-
     case GSK_TRANSFORM_NODE:
       {
         static const char * category_names[] = {