cc: Avoid duplicate work when computing draw properties using property trees

cc/trees/draw_property_utils.cc

Index: cc/trees/draw_property_utils.cc
diff --git a/cc/trees/draw_property_utils.cc b/cc/trees/draw_property_utils.cc
index a000ec6a8e218b46c02651668eaffaf9fd891dfc..5c7503e8032fb225a9a01595ef8095d99df7ac1e 100644
--- a/cc/trees/draw_property_utils.cc
+++ b/cc/trees/draw_property_utils.cc
@@ -630,9 +630,7 @@ void ComputeVisibleRectsUsingPropertyTrees(LayerImpl* root_layer,
 template <typename LayerType>
 gfx::Transform DrawTransformFromPropertyTreesInternal(
     const LayerType* layer,
-    const TransformTree& tree) {
-  const TransformNode* node = tree.Node(layer->transform_tree_index());
-
+    const TransformNode* node) {
   gfx::Transform xform;
   const bool owns_non_root_surface =
       layer->parent() && layer->has_render_surface();
@@ -653,17 +651,18 @@ gfx::Transform DrawTransformFromPropertyTreesInternal(
 
 gfx::Transform DrawTransformFromPropertyTrees(const Layer* layer,
                                               const TransformTree& tree) {
-  return DrawTransformFromPropertyTreesInternal(layer, tree);
+  return DrawTransformFromPropertyTreesInternal(
+      layer, tree.Node(layer->transform_tree_index()));
 }
 
 gfx::Transform DrawTransformFromPropertyTrees(const LayerImpl* layer,
                                               const TransformTree& tree) {
-  return DrawTransformFromPropertyTreesInternal(layer, tree);
+  return DrawTransformFromPropertyTreesInternal(
+      layer, tree.Node(layer->transform_tree_index()));
 }
 
-gfx::Transform DrawTransformOfRenderSurfaceFromPropertyTrees(
-    const RenderSurfaceImpl* render_surface,
-    const TransformTree& tree) {
+gfx::Transform SurfaceDrawTransform(const RenderSurfaceImpl* render_surface,
+                                    const TransformTree& tree) {
   const TransformNode* node = tree.Node(render_surface->TransformTreeIndex());
   gfx::Transform render_surface_transform;
   // The draw transform of root render surface is identity tranform.
@@ -681,28 +680,24 @@ gfx::Transform DrawTransformOfRenderSurfaceFromPropertyTrees(
   return render_surface_transform;
 }
 
-bool RenderSurfaceIsClippedFromPropertyTrees(
-    const RenderSurfaceImpl* render_surface,
-    const ClipTree& tree) {
-  const ClipNode* node = tree.Node(render_surface->ClipTreeIndex());
+bool SurfaceIsClipped(const RenderSurfaceImpl* render_surface,
+                      const ClipNode* clip_node) {
   // If the render surface's owning layer doesn't form a clip node, it is not
   // clipped.
-  if (render_surface->OwningLayerId() != node->owner_id)
+  if (render_surface->OwningLayerId() != clip_node->owner_id)
     return false;
-  return node->data.render_surface_is_clipped;
+  return clip_node->data.render_surface_is_clipped;
 }
 
-gfx::Rect ClipRectOfRenderSurfaceFromPropertyTrees(
-    const RenderSurfaceImpl* render_surface,
-    const ClipTree& clip_tree) {
-  if (!RenderSurfaceIsClippedFromPropertyTrees(render_surface, clip_tree))
+gfx::Rect SurfaceClipRect(const RenderSurfaceImpl* render_surface,
+                          const ClipNode* parent_clip_node,
+                          bool is_clipped) {
+  if (!is_clipped)
     return gfx::Rect();
-  const ClipNode* clip_node = clip_tree.Node(render_surface->ClipTreeIndex());
-  const ClipNode* parent_clip_node = clip_tree.parent(clip_node);
   return gfx::ToEnclosingRect(parent_clip_node->data.clip_in_target_space);
 }
 
-gfx::Transform ScreenSpaceTransformOfRenderSurfaceFromPropertyTrees(
+gfx::Transform SurfaceScreenSpaceTransform(
     const RenderSurfaceImpl* render_surface,
     const TransformTree& tree) {
   const TransformNode* node = tree.Node(render_surface->TransformTreeIndex());
@@ -721,74 +716,31 @@ gfx::Transform ScreenSpaceTransformOfRenderSurfaceFromPropertyTrees(
 template <typename LayerType>
 gfx::Transform ScreenSpaceTransformFromPropertyTreesInternal(
     LayerType* layer,
-    const TransformTree& tree) {
+    const TransformNode* node) {
   gfx::Transform xform(1, 0, 0, 1, layer->offset_to_transform_parent().x(),
                        layer->offset_to_transform_parent().y());
-  if (layer->transform_tree_index() >= 0) {
-    gfx::Transform ssxform =
-        tree.Node(layer->transform_tree_index())->data.to_screen;
-    xform.ConcatTransform(ssxform);
-    if (layer->should_flatten_transform_from_property_tree())
-      xform.FlattenTo2d();
-  }
+  gfx::Transform ssxform = node->data.to_screen;
+  xform.ConcatTransform(ssxform);
+  if (layer->should_flatten_transform_from_property_tree())
+    xform.FlattenTo2d();
   return xform;
 }
 
 gfx::Transform ScreenSpaceTransformFromPropertyTrees(
     const Layer* layer,
     const TransformTree& tree) {
-  return ScreenSpaceTransformFromPropertyTreesInternal(layer, tree);
+  return ScreenSpaceTransformFromPropertyTreesInternal(
+      layer, tree.Node(layer->transform_tree_index()));
 }
 
 gfx::Transform ScreenSpaceTransformFromPropertyTrees(
     const LayerImpl* layer,
     const TransformTree& tree) {
-  return ScreenSpaceTransformFromPropertyTreesInternal(layer, tree);
-}
-
-template <typename LayerType>
-bool ScreenSpaceTransformIsAnimatingFromPropertyTreesInternal(
-    LayerType* layer,
-    const TransformTree& tree) {
-  return tree.Node(layer->transform_tree_index())->data.to_screen_is_animated;
-}
-
-bool ScreenSpaceTransformIsAnimatingFromPropertyTrees(
-    const Layer* layer,
-    const TransformTree& tree) {
-  return ScreenSpaceTransformIsAnimatingFromPropertyTreesInternal(layer, tree);
-}
-
-bool ScreenSpaceTransformIsAnimatingFromPropertyTrees(
-    const LayerImpl* layer,
-    const TransformTree& tree) {
-  return ScreenSpaceTransformIsAnimatingFromPropertyTreesInternal(layer, tree);
+  return ScreenSpaceTransformFromPropertyTreesInternal(
+      layer, tree.Node(layer->transform_tree_index()));
 }
 
-float MaximumAnimationTargetScaleFromPropertyTrees(const LayerImpl* layer,
-                                                   const TransformTree& tree) {
-  if (!layer->layer_tree_impl()
-           ->settings()
-           .layer_transforms_should_scale_layer_contents)
-    return 0.f;
-
-  return tree.Node(layer->transform_tree_index())
-      ->data.combined_maximum_animation_target_scale;
-}
-
-float StartingAnimationScaleFromPropertyTrees(const LayerImpl* layer,
-                                              const TransformTree& tree) {
-  if (!layer->layer_tree_impl()
-           ->settings()
-           .layer_transforms_should_scale_layer_contents)
-    return 0.f;
-
-  return tree.Node(layer->transform_tree_index())
-      ->data.combined_starting_animation_scale;
-}
-
-float DrawOpacityFromPropertyTrees(const LayerImpl* layer,
-                                   const EffectTree& tree) {
+float LayerDrawOpacity(const LayerImpl* layer, const EffectTree& tree) {
   if (!layer->render_target())
     return 0.f;
 
@@ -806,9 +758,8 @@ float DrawOpacityFromPropertyTrees(const LayerImpl* layer,
   return draw_opacity;
 }
 
-float DrawOpacityOfRenderSurfaceFromPropertyTrees(
-    RenderSurfaceImpl* render_surface,
-    const EffectTree& tree) {
+float SurfaceDrawOpacity(RenderSurfaceImpl* render_surface,
+                         const EffectTree& tree) {
   const EffectNode* node = tree.Node(render_surface->EffectTreeIndex());
   float target_opacity_tree_index = render_surface->TargetEffectTreeIndex();
   if (target_opacity_tree_index < 0)
@@ -822,25 +773,20 @@ float DrawOpacityOfRenderSurfaceFromPropertyTrees(
   return draw_opacity;
 }
 
-bool CanUseLcdTextFromPropertyTrees(const LayerImpl* layer,
-                                    bool layers_always_allowed_lcd_text,
-                                    bool can_use_lcd_text,
-                                    PropertyTrees* property_trees) {
+bool LayerCanUseLcdText(const LayerImpl* layer,
+                        bool layers_always_allowed_lcd_text,
+                        bool can_use_lcd_text,
+                        const TransformNode* transform_node,
+                        const EffectNode* effect_node) {
   if (layers_always_allowed_lcd_text)
     return true;
   if (!can_use_lcd_text)
     return false;
   if (!layer->contents_opaque())
     return false;
-  DCHECK(!property_trees->transform_tree.needs_update());
-  DCHECK(!property_trees->effect_tree.needs_update());
 
-  const EffectNode* opacity_node =
-      property_trees->effect_tree.Node(layer->effect_tree_index());
-  if (opacity_node->data.screen_space_opacity != 1.f)
+  if (effect_node->data.screen_space_opacity != 1.f)
     return false;
-  const TransformNode* transform_node =
-      property_trees->transform_tree.Node(layer->transform_tree_index());
   if (!transform_node->data.node_and_ancestors_have_only_integer_translation)
     return false;
   if (static_cast<int>(layer->offset_to_transform_parent().x()) !=
@@ -852,43 +798,14 @@ bool CanUseLcdTextFromPropertyTrees(const LayerImpl* layer,
   return true;
 }
 
-gfx::Rect DrawableContentRectOfSurfaceFromPropertyTrees(
-    const RenderSurfaceImpl* render_surface,
-    const TransformTree& transform_tree) {
-  gfx::Rect drawable_content_rect =
-      gfx::ToEnclosingRect(MathUtil::MapClippedRect(
-          DrawTransformOfRenderSurfaceFromPropertyTrees(render_surface,
-                                                        transform_tree),
-          render_surface->content_rect_from_property_trees()));
-  if (render_surface->HasReplica()) {
-    drawable_content_rect.Union(gfx::ToEnclosingRect(MathUtil::MapClippedRect(
-        DrawTransformOfRenderSurfaceReplicaFromPropertyTrees(render_surface,
-                                                             transform_tree),
-        render_surface->content_rect_from_property_trees())));
-  }
-  return drawable_content_rect;
-}
-
-gfx::Rect DrawableContentRectFromPropertyTrees(
+gfx::Rect LayerDrawableContentRect(
     const LayerImpl* layer,
-    const TransformTree& transform_tree) {
-  gfx::Rect drawable_content_rect = MathUtil::MapEnclosingClippedRect(
-      DrawTransformFromPropertyTrees(layer, transform_tree),
-      gfx::Rect(layer->bounds()));
-  if (layer->is_clipped()) {
-    drawable_content_rect.Intersect(
-        layer->clip_rect_in_target_space_from_property_trees());
-  }
-  return drawable_content_rect;
-}
-
-gfx::Rect ClipRectFromPropertyTrees(const LayerImpl* layer,
-                                    const TransformTree& transform_tree) {
+    const gfx::Rect& layer_bounds_in_target_space,
+    const gfx::Rect& clip_rect) {
   if (layer->is_clipped())
-    return layer->clip_rect_in_target_space_from_property_trees();
-  return MathUtil::MapEnclosingClippedRect(
-      DrawTransformFromPropertyTrees(layer, transform_tree),
-      gfx::Rect(layer->bounds()));
+    return IntersectRects(layer_bounds_in_target_space, clip_rect);
+
+  return layer_bounds_in_target_space;
 }
 
 gfx::Transform ReplicaToSurfaceTransform(
@@ -918,23 +835,94 @@ gfx::Transform ReplicaToSurfaceTransform(
   return replica_to_surface;
 }
 
-gfx::Transform DrawTransformOfRenderSurfaceReplicaFromPropertyTrees(
-    const RenderSurfaceImpl* render_surface,
-    const TransformTree& tree) {
-  if (!render_surface->HasReplica())
-    return gfx::Transform();
-  return DrawTransformOfRenderSurfaceFromPropertyTrees(render_surface, tree) *
-         ReplicaToSurfaceTransform(render_surface, tree);
+gfx::Rect LayerClipRect(const LayerImpl* layer,
+                        const gfx::Rect& layer_bounds_in_target_space) {
+  if (layer->is_clipped())
+    return layer->clip_rect_in_target_space_from_property_trees();
+
+  return layer_bounds_in_target_space;
 }
 
-gfx::Transform ScreenSpaceTransformOfRenderSurfaceReplicaFromPropertyTrees(
-    const RenderSurfaceImpl* render_surface,
-    const TransformTree& tree) {
-  if (!render_surface->HasReplica())
-    return gfx::Transform();
-  return ScreenSpaceTransformOfRenderSurfaceFromPropertyTrees(render_surface,
-                                                              tree) *
-         ReplicaToSurfaceTransform(render_surface, tree);
+void ComputeLayerDrawPropertiesUsingPropertyTrees(

[enne (OOO), 2015/09/02 21:51:35]

I love how simple this function is!

+    const LayerImpl* layer,
+    const PropertyTrees* property_trees,
+    bool layers_always_allowed_lcd_text,
+    bool can_use_lcd_text,
+    DrawProperties* draw_properties) {
+  draw_properties->visible_layer_rect =
+      layer->visible_rect_from_property_trees();
+
+  const TransformNode* transform_node =
+      property_trees->transform_tree.Node(layer->transform_tree_index());
+  const EffectNode* effect_node =
+      property_trees->effect_tree.Node(layer->effect_tree_index());
+
+  draw_properties->target_space_transform =
+      DrawTransformFromPropertyTreesInternal(layer, transform_node);
+  draw_properties->screen_space_transform =
+      ScreenSpaceTransformFromPropertyTreesInternal(layer, transform_node);
+  draw_properties->screen_space_transform_is_animating =
+      transform_node->data.to_screen_is_animated;
+  if (layer->layer_tree_impl()
+          ->settings()
+          .layer_transforms_should_scale_layer_contents) {
+    draw_properties->maximum_animation_contents_scale =
+        transform_node->data.combined_maximum_animation_target_scale;
+    draw_properties->starting_animation_contents_scale =
+        transform_node->data.combined_starting_animation_scale;
+  } else {
+    draw_properties->maximum_animation_contents_scale = 0.f;
+    draw_properties->starting_animation_contents_scale = 0.f;
+  }
+
+  draw_properties->opacity =
+      LayerDrawOpacity(layer, property_trees->effect_tree);
+  draw_properties->can_use_lcd_text =
+      LayerCanUseLcdText(layer, layers_always_allowed_lcd_text,
+                         can_use_lcd_text, transform_node, effect_node);
+
+  gfx::Rect bounds_in_target_space = MathUtil::MapEnclosingClippedRect(
+      draw_properties->target_space_transform, gfx::Rect(layer->bounds()));
+  draw_properties->clip_rect = LayerClipRect(layer, bounds_in_target_space);
+  draw_properties->drawable_content_rect = LayerDrawableContentRect(
+      layer, bounds_in_target_space, draw_properties->clip_rect);
+}
+
+SurfaceDrawProperties::SurfaceDrawProperties()
+    : is_clipped(false), draw_opacity(0.f) {}
+
+SurfaceDrawProperties::~SurfaceDrawProperties() {}
+
+void ComputeSurfaceDrawPropertiesUsingPropertyTrees(
+    RenderSurfaceImpl* render_surface,
+    const PropertyTrees* property_trees,
+    SurfaceDrawProperties* draw_properties) {
+  const ClipNode* clip_node =
+      property_trees->clip_tree.Node(render_surface->ClipTreeIndex());
+
+  draw_properties->is_clipped = SurfaceIsClipped(render_surface, clip_node);
+  draw_properties->draw_opacity =
+      SurfaceDrawOpacity(render_surface, property_trees->effect_tree);
+  draw_properties->draw_transform =
+      SurfaceDrawTransform(render_surface, property_trees->transform_tree);
+  draw_properties->screen_space_transform = SurfaceScreenSpaceTransform(
+      render_surface, property_trees->transform_tree);
+
+  if (render_surface->HasReplica()) {
+    gfx::Transform replica_to_surface = ReplicaToSurfaceTransform(
+        render_surface, property_trees->transform_tree);
+    draw_properties->replica_draw_transform =
+        draw_properties->draw_transform * replica_to_surface;
+    draw_properties->replica_screen_space_transform =
+        draw_properties->screen_space_transform * replica_to_surface;
+  } else {
+    draw_properties->replica_draw_transform.MakeIdentity();
+    draw_properties->replica_screen_space_transform.MakeIdentity();
+  }
+
+  draw_properties->clip_rect = SurfaceClipRect(
+      render_surface, property_trees->clip_tree.parent(clip_node),
+      draw_properties->is_clipped);
 }
 
 }  // namespace cc