compositing: Implement display ports and avoid creating display lists

for items outside it.

This improves Servo's performance on large pages.

1 files changed, 5 insertions, 0 deletions

diff --git a/components/script/layout_interface.rs b/components/script/layout_interface.rs
index ad474a0daed..2ebb00d5cf8 100644
--- a/components/script/layout_interface.rs
+++ b/components/script/layout_interface.rs
@@ -11,6 +11,7 @@ use dom::node::LayoutData;
 use geom::point::Point2D;
 use geom::rect::Rect;
 use libc::uintptr_t;
+use msg::compositor_msg::LayerId;
 use msg::constellation_msg::{PipelineExitType, WindowSizeData};
 use msg::compositor_msg::Epoch;
 use net_traits::PendingAsyncLoad;
@@ -47,6 +48,10 @@ pub enum Msg {
     /// Requests that the layout task render the next frame of all animations.
     TickAnimations,
 
+    /// Updates the layout visible rects, affecting the area that display lists will be constructed
+    /// for.
+    SetVisibleRects(Vec<(LayerId, Rect<Au>)>),
+
     /// Destroys layout data associated with a DOM node.
     ///
     /// TODO(pcwalton): Maybe think about batching to avoid message traffic.