1 files changed, 75 insertions, 0 deletions
diff --git a/components/shared/script_layout/rpc.rs b/components/shared/script_layout/rpc.rs
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+++ b/components/shared/script_layout/rpc.rs
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+/* 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 app_units::Au;
+use euclid::default::Rect;
+use euclid::Size2D;
+use script_traits::UntrustedNodeAddress;
+use servo_arc::Arc;
+use style::properties::style_structs::Font;
+use style_traits::CSSPixel;
+use webrender_api::ExternalScrollId;
+
+/// Synchronous messages that script can send to layout.
+///
+/// In general, you should use messages to talk to Layout. Use the RPC interface
+/// if and only if the work is
+///
+///   1) read-only with respect to LayoutThreadData,
+///   2) small,
+///   3) and really needs to be fast.
+pub trait LayoutRPC {
+    /// Requests the dimensions of the content box, as in the `getBoundingClientRect()` call.
+    fn content_box(&self) -> ContentBoxResponse;
+    /// Requests the dimensions of all the content boxes, as in the `getClientRects()` call.
+    fn content_boxes(&self) -> ContentBoxesResponse;
+    /// Requests the geometry of this node. Used by APIs such as `clientTop`.
+    fn node_geometry(&self) -> NodeGeometryResponse;
+    /// Requests the scroll geometry of this node. Used by APIs such as `scrollTop`.
+    fn scrolling_area(&self) -> NodeGeometryResponse;
+    /// Requests the scroll id of this node. Used by APIs such as `scrollTop`
+    fn node_scroll_id(&self) -> NodeScrollIdResponse;
+    /// Query layout for the resolved value of a given CSS property
+    fn resolved_style(&self) -> ResolvedStyleResponse;
+    /// Query layout to get the resolved font style for canvas.
+    fn resolved_font_style(&self) -> Option<Arc<Font>>;
+    fn offset_parent(&self) -> OffsetParentResponse;
+    fn text_index(&self) -> TextIndexResponse;
+    /// Requests the list of nodes from the given point.
+    fn nodes_from_point_response(&self) -> Vec<UntrustedNodeAddress>;
+    /// Query layout to get the inner text for a given element.
+    fn element_inner_text(&self) -> String;
+    /// Get the dimensions of an iframe's inner window.
+    fn inner_window_dimensions(&self) -> Option<Size2D<f32, CSSPixel>>;
+}
+
+pub struct ContentBoxResponse(pub Option<Rect<Au>>);
+
+pub struct ContentBoxesResponse(pub Vec<Rect<Au>>);
+
+pub struct NodeGeometryResponse {
+    pub client_rect: Rect<i32>,
+}
+
+pub struct NodeScrollIdResponse(pub ExternalScrollId);
+
+pub struct ResolvedStyleResponse(pub String);
+
+#[derive(Clone)]
+pub struct OffsetParentResponse {
+    pub node_address: Option<UntrustedNodeAddress>,
+    pub rect: Rect<Au>,
+}
+
+impl OffsetParentResponse {
+    pub fn empty() -> OffsetParentResponse {
+        OffsetParentResponse {
+            node_address: None,
+            rect: Rect::zero(),
+        }
+    }
+}
+
+#[derive(Clone)]
+pub struct TextIndexResponse(pub Option<usize>);