Auto merge of #14938 - servo:gfx-traits, r=nox

Various cleanup around gfx_traits.

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components/compositing/compositor.rs

@@ -11,8 +11,8 @@ use euclid::Point2D;
 use euclid::point::TypedPoint2D;
 use euclid::scale_factor::ScaleFactor;
 use euclid::size::TypedSize2D;
-use gfx_traits::{DevicePixel, LayerPixel, ScrollRootId};
-use gfx_traits::{Epoch, FrameTreeId, FragmentType};
+use gfx_traits::{DevicePixel, ScrollRootId};
+use gfx_traits::{Epoch, FragmentType};
 use gleam::gl;
 use gleam::gl::types::{GLint, GLsizei};
 use image::{DynamicImage, ImageFormat, RgbImage};
@@ -108,6 +108,22 @@ enum ReadyState {
     ReadyToSaveImage,
 }
 
+#[derive(PartialEq, Eq, Debug, Copy, Clone)]
+struct FrameTreeId(u32);
+
+impl FrameTreeId {
+    pub fn next(&mut self) {
+        self.0 += 1;
+    }
+}
+
+/// One pixel in layer coordinate space.
+///
+/// This unit corresponds to a "pixel" in layer coordinate space, which after scaling and
+/// transformation becomes a device pixel.
+#[derive(Copy, Clone, Debug)]
+enum LayerPixel {}
+
 /// NB: Never block on the constellation, because sometimes the constellation blocks on us.
 pub struct IOCompositor<Window: WindowMethods> {
     /// The application window.

components/gfx/Cargo.toml

@@ -29,7 +29,6 @@ net_traits = {path = "../net_traits"}
 ordered-float = "0.2.2"
 plugins = {path = "../plugins"}
 range = {path = "../range"}
-rustc-serialize = "0.3"
 serde = "0.8"
 servo_atoms = {path = "../atoms"}
 servo_geometry = {path = "../geometry"}

components/gfx/display_list/mod.rs

@@ -19,7 +19,7 @@ use euclid::{Matrix4D, Point2D, Rect, Size2D};
 use euclid::num::{One, Zero};
 use euclid::rect::TypedRect;
 use euclid::side_offsets::SideOffsets2D;
-use gfx_traits::{ScrollPolicy, ScrollRootId, StackingContextId};
+use gfx_traits::{ScrollRootId, StackingContextId};
 use gfx_traits::print_tree::PrintTree;
 use ipc_channel::ipc::IpcSharedMemory;
 use msg::constellation_msg::PipelineId;
@@ -34,7 +34,7 @@ use style::computed_values::{border_style, filter, image_rendering, mix_blend_mo
 use style_traits::cursor::Cursor;
 use text::TextRun;
 use text::glyph::ByteIndex;
-use webrender_traits::{self, ColorF, GradientStop, WebGLContextId};
+use webrender_traits::{self, ColorF, GradientStop, ScrollPolicy, WebGLContextId};
 
 pub use style::dom::OpaqueNode;
 
@@ -129,7 +129,7 @@ impl DisplayList {
         // Convert the parent translated point into stacking context local transform space if the
         // stacking context isn't fixed.  If it's fixed, we need to use the client point anyway.
         debug_assert!(stacking_context.context_type == StackingContextType::Real);
-        let is_fixed = stacking_context.scroll_policy == ScrollPolicy::FixedPosition;
+        let is_fixed = stacking_context.scroll_policy == ScrollPolicy::Fixed;
         let translated_point = if is_fixed {
             *client_point
         } else {
@@ -251,7 +251,7 @@ impl<'a> Iterator for DisplayListTraversal<'a> {
 /// Display list sections that make up a stacking context. Each section  here refers
 /// to the steps in CSS 2.1 Appendix E.
 ///
-#[derive(Clone, Copy, Debug, Deserialize, Eq, HeapSizeOf, Ord, PartialEq, PartialOrd, RustcEncodable, Serialize)]
+#[derive(Clone, Copy, Debug, Deserialize, Eq, HeapSizeOf, Ord, PartialEq, PartialOrd, Serialize)]
 pub enum DisplayListSection {
     BackgroundAndBorders,
     BlockBackgroundsAndBorders,
@@ -259,7 +259,7 @@ pub enum DisplayListSection {
     Outlines,
 }
 
-#[derive(Clone, Copy, Debug, Deserialize, Eq, HeapSizeOf, Ord, PartialEq, PartialOrd, RustcEncodable, Serialize)]
+#[derive(Clone, Copy, Debug, Deserialize, Eq, HeapSizeOf, Ord, PartialEq, PartialOrd, Serialize)]
 pub enum StackingContextType {
     Real,
     PseudoPositioned,

components/gfx/lib.rs

@@ -58,7 +58,6 @@ extern crate net_traits;
 extern crate ordered_float;
 #[macro_use]
 extern crate range;
-extern crate rustc_serialize;
 extern crate serde;
 #[macro_use]
 extern crate serde_derive;

components/gfx_traits/Cargo.toml

@@ -14,6 +14,5 @@ heapsize = "0.3.0"
 heapsize_derive = "0.1"
 plugins = {path = "../plugins"}
 range = {path = "../range"}
-rustc-serialize = "0.3"
 serde = "0.8"
 serde_derive = "0.8"

components/gfx_traits/lib.rs

@@ -14,7 +14,6 @@ extern crate heapsize;
 #[macro_use] extern crate heapsize_derive;
 #[macro_use]
 extern crate range;
-extern crate rustc_serialize;
 extern crate serde;
 #[macro_use]
 extern crate serde_derive;
@@ -41,43 +40,9 @@ const SPECIAL_STACKING_CONTEXT_ID_MASK: usize = 0xffff;
 /// One hardware pixel.
 ///
 /// This unit corresponds to the smallest addressable element of the display hardware.
-#[derive(Copy, Clone, RustcEncodable, Debug)]
+#[derive(Copy, Clone, Debug)]
 pub enum DevicePixel {}
 
-/// One pixel in layer coordinate space.
-///
-/// This unit corresponds to a "pixel" in layer coordinate space, which after scaling and
-/// transformation becomes a device pixel.
-#[derive(Copy, Clone, RustcEncodable, Debug)]
-pub enum LayerPixel {}
-
-#[derive(Clone, Copy, Debug, PartialEq)]
-pub enum LayerKind {
-    NoTransform,
-    HasTransform,
-}
-
-#[derive(Clone, PartialEq, Eq, Copy, Hash, Deserialize, Serialize, HeapSizeOf)]
-pub enum LayerType {
-    /// A layer for the fragment body itself.
-    FragmentBody,
-    /// An extra layer created for a DOM fragments with overflow:scroll.
-    OverflowScroll,
-    /// A layer created to contain ::before pseudo-element content.
-    BeforePseudoContent,
-    /// A layer created to contain ::after pseudo-element content.
-    AfterPseudoContent,
-}
-
-/// The scrolling policy of a layer.
-#[derive(Clone, PartialEq, Eq, Copy, Deserialize, Serialize, Debug, HeapSizeOf)]
-pub enum ScrollPolicy {
-    /// These layers scroll when the parent receives a scrolling message.
-    Scrollable,
-    /// These layers do not scroll when the parent receives a scrolling message.
-    FixedPosition,
-}
-
 /// A newtype struct for denoting the age of messages; prevents race conditions.
 #[derive(PartialEq, Eq, Debug, Copy, Clone, PartialOrd, Ord, Deserialize, Serialize)]
 pub struct Epoch(pub u32);
@@ -88,15 +53,6 @@ impl Epoch {
     }
 }
 
-#[derive(PartialEq, Eq, Debug, Copy, Clone)]
-pub struct FrameTreeId(pub u32);
-
-impl FrameTreeId {
-    pub fn next(&mut self) {
-        self.0 += 1;
-    }
-}
-
 /// A unique ID for every stacking context.
 #[derive(Clone, Copy, Debug, Deserialize, Eq, Hash, HeapSizeOf, PartialEq, Serialize)]
 pub struct StackingContextId(
@@ -128,37 +84,11 @@ impl StackingContextId {
         }
     }
 
-    /// Returns an ID for the stacking context that forms the outer stacking context of an element
-    /// with `overflow: scroll`.
-    #[inline(always)]
-    pub fn new_outer(fragment_type: FragmentType) -> StackingContextId {
-        StackingContextId(StackingContextId::next_special_id() | (fragment_type as usize))
-    }
-
-    #[inline]
-    pub fn fragment_type(&self) -> FragmentType {
-        FragmentType::from_usize(self.0 & 3)
-    }
-
-    #[inline]
-    pub fn id(&self) -> usize {
-        self.0 & !3
-    }
-
     /// Returns the stacking context ID for the outer document/layout root.
     #[inline]
     pub fn root() -> StackingContextId {
         StackingContextId(0)
     }
-
-    /// Returns true if this is a special stacking context.
-    ///
-    /// A special stacking context is a stacking context that is one of (a) the outer stacking
-    /// context of an element with `overflow: scroll`; (b) generated content; (c) both (a) and (b).
-    #[inline]
-    pub fn is_special(&self) -> bool {
-        (self.0 & !SPECIAL_STACKING_CONTEXT_ID_MASK) == 0
-    }
 }
 
 /// A unique ID for every scrolling root.
@@ -211,11 +141,6 @@ impl ScrollRootId {
     pub fn fragment_type(&self) -> FragmentType {
         FragmentType::from_usize(self.0 & 3)
     }
-
-    #[inline]
-    pub fn to_stacking_context_id(&self) -> StackingContextId {
-        StackingContextId(self.0)
-    }
 }
 
 /// The type of fragment that a stacking context represents.
@@ -246,7 +171,7 @@ impl FragmentType {
 }
 
 int_range_index! {
-    #[derive(Deserialize, Serialize, RustcEncodable)]
+    #[derive(Deserialize, Serialize)]
     #[doc = "An index that refers to a byte offset in a text run. This could \
              point to the middle of a glyph."]
     #[derive(HeapSizeOf)]

components/layout/display_list_builder.rs

@@ -27,7 +27,7 @@ use gfx::display_list::{GradientDisplayItem, IframeDisplayItem, ImageDisplayItem
 use gfx::display_list::{LineDisplayItem, OpaqueNode};
 use gfx::display_list::{SolidColorDisplayItem, ScrollRoot, StackingContext, StackingContextType};
 use gfx::display_list::{TextDisplayItem, TextOrientation, WebGLDisplayItem, WebRenderImageInfo};
-use gfx_traits::{ScrollPolicy, ScrollRootId, StackingContextId};
+use gfx_traits::{ScrollRootId, StackingContextId};
 use inline::{FIRST_FRAGMENT_OF_ELEMENT, InlineFlow, LAST_FRAGMENT_OF_ELEMENT};
 use ipc_channel::ipc;
 use list_item::ListItemFlow;
@@ -58,7 +58,7 @@ use style::values::computed::{AngleOrCorner, Gradient, GradientKind, LengthOrPer
 use style::values::specified::{HorizontalDirection, VerticalDirection};
 use style_traits::cursor::Cursor;
 use table_cell::CollapsedBordersForCell;
-use webrender_traits::{ColorF, GradientStop};
+use webrender_traits::{ColorF, GradientStop, ScrollPolicy};
 
 trait RgbColor {
     fn rgb(r: u8, g: u8, b: u8) -> Self;
@@ -1912,7 +1912,7 @@ impl BlockFlowDisplayListBuilding for BlockFlow {
                                               parent_scroll_root_id: ScrollRootId,
                                               state: &mut DisplayListBuildState) {
         let scroll_policy = if self.is_fixed() {
-            ScrollPolicy::FixedPosition
+            ScrollPolicy::Fixed
         } else {
             ScrollPolicy::Scrollable
         };

components/layout/webrender_helpers.rs

@@ -11,7 +11,7 @@ use app_units::Au;
 use euclid::{Point2D, Rect, Size2D};
 use gfx::display_list::{BorderRadii, BoxShadowClipMode, ClippingRegion};
 use gfx::display_list::{DisplayItem, DisplayList, DisplayListTraversal, StackingContextType};
-use gfx_traits::{FragmentType, ScrollPolicy, ScrollRootId};
+use gfx_traits::{FragmentType, ScrollRootId};
 use msg::constellation_msg::PipelineId;
 use style::computed_values::{image_rendering, mix_blend_mode};
 use style::computed_values::filter::{self, Filter};
@@ -337,16 +337,11 @@ impl WebRenderDisplayItemConverter for DisplayItem {
                 let stacking_context = &item.stacking_context;
                 debug_assert!(stacking_context.context_type == StackingContextType::Real);
 
-                let webrender_scroll_policy = match stacking_context.scroll_policy {
-                    ScrollPolicy::Scrollable => webrender_traits::ScrollPolicy::Scrollable,
-                    ScrollPolicy::FixedPosition => webrender_traits::ScrollPolicy::Fixed,
-                };
-
                 let clip = builder.new_clip_region(&stacking_context.overflow.to_rectf(),
                                                    vec![],
                                                    None);
 
-                builder.push_stacking_context(webrender_scroll_policy,
+                builder.push_stacking_context(stacking_context.scroll_policy,
                                               stacking_context.bounds.to_rectf(),
                                               clip,
                                               stacking_context.z_index,