2020: paint background-color

8 files changed, 143 insertions, 24 deletions

diff --git a/Cargo.lock b/Cargo.lock
index f6c6c03ddf0..da1e5f81bb6 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2477,6 +2477,7 @@ version = "0.0.1"
 dependencies = [
  "app_units",
  "atomic_refcell",
+ "cssparser",
  "euclid",
  "gfx",
  "ipc-channel",
diff --git a/components/layout_2020/Cargo.toml b/components/layout_2020/Cargo.toml
index cacece15eb5..69b0bea014e 100644
--- a/components/layout_2020/Cargo.toml
+++ b/components/layout_2020/Cargo.toml
@@ -15,6 +15,7 @@ doctest = false
 [dependencies]
 app_units = "0.7"
 atomic_refcell = "0.1"
+cssparser = "0.27"
 euclid = "0.20"
 gfx = {path = "../gfx"}
 ipc-channel = "0.12"
diff --git a/components/layout_2020/display_list.rs b/components/layout_2020/display_list.rs
new file mode 100644
index 00000000000..cd3d3b103db
--- /dev/null
+++ b/components/layout_2020/display_list.rs
@@ -0,0 +1,106 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use crate::fragments::{BoxFragment, Fragment};
+use crate::geom::physical::{Rect, Vec2};
+use crate::style_ext::ComputedValuesExt;
+use app_units::Au;
+use style::values::computed::Length;
+use webrender_api::CommonItemProperties;
+
+pub struct DisplayListBuilder {
+    pipeline_id: webrender_api::PipelineId,
+    pub wr: webrender_api::DisplayListBuilder,
+    pub is_contentful: bool,
+}
+
+impl DisplayListBuilder {
+    pub fn new(
+        pipeline_id: webrender_api::PipelineId,
+        viewport_size: webrender_api::units::LayoutSize,
+    ) -> Self {
+        Self {
+            pipeline_id,
+            is_contentful: false,
+            wr: webrender_api::DisplayListBuilder::new(pipeline_id, viewport_size),
+        }
+    }
+}
+
+/// Contentful paint, for the purpose of
+/// https://w3c.github.io/paint-timing/#first-contentful-paint
+/// (i.e. the display list contains items of type text,
+/// image, non-white canvas or SVG). Used by metrics.
+pub struct IsContentful(pub bool);
+
+impl Fragment {
+    pub(crate) fn build_display_list(
+        &self,
+        builder: &mut DisplayListBuilder,
+        is_contentful: &mut IsContentful,
+        containing_block: &Rect<Length>,
+    ) {
+        match self {
+            Fragment::Box(b) => b.build_display_list(builder, is_contentful, containing_block),
+            Fragment::Anonymous(a) => {
+                let rect = a
+                    .rect
+                    .to_physical(a.mode, containing_block)
+                    .translate(&containing_block.top_left);
+                for child in &a.children {
+                    child.build_display_list(builder, is_contentful, &rect)
+                }
+            },
+            Fragment::Text(_) => {
+                is_contentful.0 = true;
+                // FIXME
+            },
+        }
+    }
+}
+
+impl BoxFragment {
+    fn build_display_list(
+        &self,
+        builder: &mut DisplayListBuilder,
+        is_contentful: &mut IsContentful,
+        containing_block: &Rect<Length>,
+    ) {
+        let background_color = self
+            .style
+            .resolve_color(self.style.clone_background_color());
+        if background_color.alpha > 0 {
+            let clip_rect = self
+                .border_rect()
+                .to_physical(self.style.writing_mode(), containing_block)
+                .translate(&containing_block.top_left)
+                .into();
+            let common = CommonItemProperties {
+                clip_rect,
+                clip_id: webrender_api::ClipId::root(builder.pipeline_id),
+                spatial_id: webrender_api::SpatialId::root_scroll_node(builder.pipeline_id),
+                hit_info: None,
+                // TODO(gw): Make use of the WR backface visibility functionality.
+                is_backface_visible: true,
+            };
+            builder.wr.push_rect(&common, rgba(background_color))
+        }
+        let content_rect = self
+            .content_rect
+            .to_physical(self.style.writing_mode(), containing_block)
+            .translate(&containing_block.top_left);
+        for child in &self.children {
+            child.build_display_list(builder, is_contentful, &content_rect)
+        }
+    }
+}
+
+fn rgba(rgba: cssparser::RGBA) -> webrender_api::ColorF {
+    webrender_api::ColorF::new(
+        rgba.red_f32(),
+        rgba.green_f32(),
+        rgba.blue_f32(),
+        rgba.alpha_f32(),
+    )
+}
diff --git a/components/layout_2020/flow/root.rs b/components/layout_2020/flow/root.rs
index ba473abc410..54cc1eef07f 100644
--- a/components/layout_2020/flow/root.rs
+++ b/components/layout_2020/flow/root.rs
@@ -2,11 +2,12 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+use crate::display_list::IsContentful;
 use crate::dom_traversal::{Contents, NodeExt};
 use crate::flow::construct::ContainsFloats;
 use crate::flow::float::FloatBox;
 use crate::flow::{BlockContainer, BlockFormattingContext, BlockLevelBox};
-use crate::fragments::{Fragment, IsContentful};
+use crate::fragments::Fragment;
 use crate::geom;
 use crate::geom::flow_relative::Vec2;
 use crate::positioned::AbsolutelyPositionedBox;
@@ -20,8 +21,8 @@ use servo_arc::Arc;
 use style::context::SharedStyleContext;
 use style::properties::ComputedValues;
 use style::values::computed::{Length, LengthOrAuto};
+use style::Zero;
 use style_traits::CSSPixel;
-use webrender_api::DisplayListBuilder;
 
 pub struct BoxTreeRoot(BlockFormattingContext);
 pub struct FragmentTreeRoot(Vec<Fragment>);
@@ -132,10 +133,25 @@ impl BoxTreeRoot {
 }
 
 impl FragmentTreeRoot {
-    pub fn build_display_list(&self, builder: &mut DisplayListBuilder) -> IsContentful {
+    pub fn build_display_list(
+        &self,
+        builder: &mut crate::display_list::DisplayListBuilder,
+        pipeline_id: msg::constellation_msg::PipelineId,
+        viewport_size: webrender_api::units::LayoutSize,
+    ) -> IsContentful {
+        let containing_block = geom::physical::Rect {
+            top_left: geom::physical::Vec2 {
+                x: Length::zero(),
+                y: Length::zero(),
+            },
+            size: geom::physical::Vec2 {
+                x: Length::new(viewport_size.width),
+                y: Length::new(viewport_size.height),
+            },
+        };
         let mut is_contentful = IsContentful(false);
         for fragment in &self.0 {
-            fragment.build_display_list(builder, &mut is_contentful)
+            fragment.build_display_list(builder, &mut is_contentful, &containing_block)
         }
         is_contentful
     }
diff --git a/components/layout_2020/fragments.rs b/components/layout_2020/fragments.rs
index ad1ebd41359..ceb2fdf7971 100644
--- a/components/layout_2020/fragments.rs
+++ b/components/layout_2020/fragments.rs
@@ -9,7 +9,6 @@ use servo_arc::Arc;
 use style::properties::ComputedValues;
 use style::values::computed::Length;
 use style::Zero;
-use webrender_api::DisplayListBuilder;
 
 pub(crate) enum Fragment {
     Box(BoxFragment),
@@ -124,18 +123,3 @@ impl CollapsedMargin {
         self.max_positive + self.min_negative
     }
 }
-
-/// Contentful paint, for the purpose of
-/// https://w3c.github.io/paint-timing/#first-contentful-paint
-/// (i.e. the display list contains items of type text,
-/// image, non-white canvas or SVG). Used by metrics.
-pub struct IsContentful(pub bool);
-
-impl Fragment {
-    pub(crate) fn build_display_list(
-        &self,
-        builder: &mut DisplayListBuilder,
-        is_contentful: &mut IsContentful,
-    ) {
-    }
-}
diff --git a/components/layout_2020/geom.rs b/components/layout_2020/geom.rs
index af8d37393b5..a56ee5c7613 100644
--- a/components/layout_2020/geom.rs
+++ b/components/layout_2020/geom.rs
@@ -332,3 +332,12 @@ impl From<physical::Rect<Length>> for Rect<CSSPixel> {
         }
     }
 }
+
+impl From<physical::Rect<Length>> for webrender_api::units::LayoutRect {
+    fn from(r: physical::Rect<Length>) -> Self {
+        Rect {
+            origin: Point::new(r.top_left.x.px(), r.top_left.y.px()),
+            size: Size::new(r.size.x.px(), r.size.y.px()),
+        }
+    }
+}
diff --git a/components/layout_2020/lib.rs b/components/layout_2020/lib.rs
index b7578713f5d..5c046feecd7 100644
--- a/components/layout_2020/lib.rs
+++ b/components/layout_2020/lib.rs
@@ -17,6 +17,7 @@ use style::Zero;
 
 pub mod context;
 pub mod data;
+pub mod display_list;
 mod dom_traversal;
 mod element_data;
 mod flow;
diff --git a/components/layout_thread_2020/lib.rs b/components/layout_thread_2020/lib.rs
index 1c0ee67a268..13cf35975ee 100644
--- a/components/layout_thread_2020/lib.rs
+++ b/components/layout_thread_2020/lib.rs
@@ -35,6 +35,7 @@ use gfx_traits::{node_id_from_scroll_id, Epoch};
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
 use ipc_channel::router::ROUTER;
 use layout::context::LayoutContext;
+use layout::display_list::DisplayListBuilder;
 use layout::query::{
     process_content_box_request, process_content_boxes_request, LayoutRPCImpl, LayoutThreadData,
 };
@@ -1271,9 +1272,9 @@ impl LayoutThread {
             self.viewport_size.width.to_f32_px(),
             self.viewport_size.height.to_f32_px(),
         ));
-        let mut display_list =
-            webrender_api::DisplayListBuilder::new(self.id.to_webrender(), viewport_size);
-        let is_contentful = fragment_tree.build_display_list(&mut display_list);
+        let mut display_list = DisplayListBuilder::new(self.id.to_webrender(), viewport_size);
+        let is_contentful =
+            fragment_tree.build_display_list(&mut display_list, self.id, viewport_size);
 
         debug!("Layout done!");
 
@@ -1292,7 +1293,7 @@ impl LayoutThread {
             webrender_api::Epoch(epoch.0),
             None,
             viewport_size,
-            display_list.finalize(),
+            display_list.wr.finalize(),
             true,
         );
         txn.generate_frame();