Auto merge of #467 - mrobinson:scroll_id, r=glennw

Replace ServoStackingContextId with ServoScrollRootId

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Author: bors-servo

webrender/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "webrender"
-version = "0.7.0"
+version = "0.8.0"
 authors = ["Glenn Watson <gw@intuitionlibrary.com>"]
 license = "MPL-2.0"
 repository = "https://github.com/servo/webrender"

webrender/src/frame.rs

@@ -269,10 +269,10 @@ impl Frame {
         let mut result = vec![];
         for (scroll_layer_id, scroll_layer) in &self.layers {
             match scroll_layer_id.info {
-                ScrollLayerInfo::Scrollable(_) => {
+                ScrollLayerInfo::Scrollable(_, servo_scroll_root_id) => {
                     result.push(ScrollLayerState {
                         pipeline_id: scroll_layer.pipeline_id,
-                        stacking_context_id: scroll_layer.stacking_context_id,
+                        scroll_root_id: servo_scroll_root_id,
                         scroll_offset: scroll_layer.scrolling.offset,
                     })
                 }
@@ -394,16 +394,14 @@ impl Frame {
                     Layer::new(&root_viewport,
                                root_stacking_context.stacking_context.overflow.size,
                                &Matrix4D::identity(),
-                               root_pipeline_id,
-                               root_stacking_context.stacking_context.servo_id));
+                               root_pipeline_id));
 
                 self.layers.insert(
                     root_scroll_layer_id,
                     Layer::new(&root_viewport,
                                root_stacking_context.stacking_context.overflow.size,
                                &Matrix4D::identity(),
-                               root_pipeline_id,
-                               root_stacking_context.stacking_context.servo_id));
+                               root_pipeline_id));
 
                 // Work around borrow check on resource cache
                 {
@@ -636,8 +634,7 @@ impl Frame {
                             let layer = Layer::new(&inner_stacking_context.bounds,
                                                    inner_stacking_context.overflow.size,
                                                    &transform,
-                                                   parent_info.pipeline_id,
-                                                   inner_stacking_context.servo_id);
+                                                   parent_info.pipeline_id);
 
                             debug_assert!(parent_info.current_scroll_layer_id != inner_scroll_layer_id);
                             self.layers
@@ -696,8 +693,7 @@ impl Frame {
                                     Layer::new(&iframe_rect,
                                                iframe_stacking_context.overflow.size,
                                                &transform,
-                                               pipeline.pipeline_id,
-                                               iframe_stacking_context.servo_id));
+                                               pipeline.pipeline_id));
 
                         let iframe_scroll_layer_id = iframe_stacking_context.scroll_layer_id.unwrap();
 
@@ -706,8 +702,7 @@ impl Frame {
                                     Layer::new(&iframe_rect,
                                                iframe_stacking_context.overflow.size,
                                                &transform,
-                                               pipeline.pipeline_id,
-                                               iframe_stacking_context.servo_id));
+                                               pipeline.pipeline_id));
 
                         self.layers
                             .get_mut(&scroll_layer_id)

webrender/src/layer.rs

@@ -4,7 +4,7 @@
 
 use euclid::{Matrix4D, Point2D, Rect, Size2D};
 use spring::{DAMPING, STIFFNESS, Spring};
-use webrender_traits::{PipelineId, ScrollLayerId, ServoStackingContextId};
+use webrender_traits::{PipelineId, ScrollLayerId};
 
 pub struct Layer {
     // Manages scrolling offset, overscroll state etc.
@@ -31,10 +31,6 @@ pub struct Layer {
     // Pipeline that this layer belongs to
     pub pipeline_id: PipelineId,
 
-    // Accounting information for mapping to servo stacking contexts.
-    // TODO(gw): Can we remove this somehow?
-    pub stacking_context_id: ServoStackingContextId,
-
     // Child layers
     pub children: Vec<ScrollLayerId>,
 }
@@ -43,8 +39,7 @@ impl Layer {
     pub fn new(local_viewport_rect: &Rect<f32>,
                content_size: Size2D<f32>,
                local_transform: &Matrix4D<f32>,
-               pipeline_id: PipelineId,
-               stacking_context_id: ServoStackingContextId)
+               pipeline_id: PipelineId)
                -> Layer {
         Layer {
             scrolling: ScrollingState::new(),
@@ -56,7 +51,6 @@ impl Layer {
             local_transform: *local_transform,
             children: Vec::new(),
             pipeline_id: pipeline_id,
-            stacking_context_id: stacking_context_id,
         }
     }
 

webrender_traits/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "webrender_traits"
-version = "0.7.0"
+version = "0.8.0"
 authors = ["Glenn Watson <gw@intuitionlibrary.com>"]
 license = "MPL-2.0"
 repository = "https://github.com/servo/webrender"

webrender_traits/src/display_item.rs

@@ -5,7 +5,7 @@
 use display_list::AuxiliaryListsBuilder;
 use euclid::{Rect, Size2D};
 use {BorderRadius, BorderDisplayItem, ClipRegion, ColorF, ComplexClipRegion};
-use {FontKey, ImageKey, PipelineId, ScrollLayerId, ScrollLayerInfo};
+use {FontKey, ImageKey, PipelineId, ScrollLayerId, ScrollLayerInfo, ServoScrollRootId};
 
 impl BorderDisplayItem {
     pub fn top_left_inner_radius(&self) -> Size2D<f32> {
@@ -103,10 +103,13 @@ impl ImageKey {
 }
 
 impl ScrollLayerId {
-    pub fn new(pipeline_id: PipelineId, index: usize) -> ScrollLayerId {
+    pub fn new(pipeline_id: PipelineId,
+               index: usize,
+               scroll_root_id: ServoScrollRootId)
+               -> ScrollLayerId {
         ScrollLayerId {
             pipeline_id: pipeline_id,
-            info: ScrollLayerInfo::Scrollable(index),
+            info: ScrollLayerInfo::Scrollable(index, scroll_root_id),
         }
     }
 

webrender_traits/src/stacking_context.rs

@@ -4,12 +4,10 @@
 
 use display_list::AuxiliaryListsBuilder;
 use euclid::{Matrix4D, Rect};
-use {FilterOp, MixBlendMode, ScrollLayerId, ScrollPolicy};
-use {ServoStackingContextId, StackingContext};
+use {FilterOp, MixBlendMode, ScrollLayerId, ScrollPolicy, StackingContext};
 
 impl StackingContext {
-    pub fn new(servo_id: ServoStackingContextId,
-               scroll_layer_id: Option<ScrollLayerId>,
+    pub fn new(scroll_layer_id: Option<ScrollLayerId>,
                scroll_policy: ScrollPolicy,
                bounds: Rect<f32>,
                overflow: Rect<f32>,
@@ -22,7 +20,6 @@ impl StackingContext {
                auxiliary_lists_builder: &mut AuxiliaryListsBuilder)
                -> StackingContext {
         StackingContext {
-            servo_id: servo_id,
             scroll_layer_id: scroll_layer_id,
             scroll_policy: scroll_policy,
             bounds: bounds,

webrender_traits/src/types.rs

@@ -397,13 +397,13 @@ pub struct ScrollLayerId {
 #[derive(Clone, Copy, Debug, Deserialize, Eq, Hash, PartialEq, Serialize)]
 pub enum ScrollLayerInfo {
     Fixed,
-    Scrollable(usize)
+    Scrollable(usize, ServoScrollRootId)
 }
 
 #[derive(Clone, Deserialize, Serialize)]
 pub struct ScrollLayerState {
     pub pipeline_id: PipelineId,
-    pub stacking_context_id: ServoStackingContextId,
+    pub scroll_root_id: ServoScrollRootId,
     pub scroll_offset: Point2D<f32>,
 }
 
@@ -414,7 +414,7 @@ pub enum ScrollPolicy {
 }
 
 #[derive(Clone, Copy, Debug, Deserialize, Eq, Hash, PartialEq, Serialize)]
-pub struct ServoStackingContextId(pub FragmentType, pub usize);
+pub struct ServoScrollRootId(pub usize);
 
 #[derive(Clone, Copy, Debug, Deserialize, PartialEq, Serialize)]
 pub enum SpecificDisplayItem {
@@ -436,7 +436,6 @@ pub enum SpecificDisplayListItem {
 
 #[derive(Clone, Deserialize, Serialize)]
 pub struct StackingContext {
-    pub servo_id: ServoStackingContextId,
     pub scroll_layer_id: Option<ScrollLayerId>,
     pub scroll_policy: ScrollPolicy,
     pub bounds: Rect<f32>,