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Diffstat (limited to 'components/shared/script/compositor.rs')
| -rw-r--r-- | components/shared/script/compositor.rs | 334 |
1 files changed, 0 insertions, 334 deletions
diff --git a/components/shared/script/compositor.rs b/components/shared/script/compositor.rs deleted file mode 100644 index e66c3bf8227..00000000000 --- a/components/shared/script/compositor.rs +++ /dev/null @@ -1,334 +0,0 @@ -/* 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/. */ - -//! Defines data structures which are consumed by the Compositor. - -use embedder_traits::Cursor; -use serde::{Deserialize, Serialize}; -use webrender_api::units::{LayoutSize, LayoutVector2D}; -use webrender_api::{Epoch, ExternalScrollId, PipelineId, ScrollLocation, SpatialId}; - -/// The scroll sensitivity of a scroll node ie whether it can be scrolled due to input event and -/// script events or only script events. -#[derive(Clone, Copy, Debug, Deserialize, PartialEq, Serialize)] -pub enum ScrollSensitivity { - /// This node can be scrolled by input and script events. - ScriptAndInputEvents, - /// This node can only be scrolled by script events. - Script, -} - -/// Information that Servo keeps alongside WebRender display items -/// in order to add more context to hit test results. -#[derive(Debug, Deserialize, Serialize)] -pub struct HitTestInfo { - /// The id of the node of this hit test item. - pub node: u64, - - /// The cursor of this node's hit test item. - pub cursor: Option<Cursor>, - - /// The id of the [ScrollTree] associated with this hit test item. - pub scroll_tree_node: ScrollTreeNodeId, -} - -/// An id for a ScrollTreeNode in the ScrollTree. This contains both the index -/// to the node in the tree's array of nodes as well as the corresponding SpatialId -/// for the SpatialNode in the WebRender display list. -#[derive(Clone, Copy, Debug, Default, Deserialize, PartialEq, Serialize)] -pub struct ScrollTreeNodeId { - /// The index of this scroll tree node in the tree's array of nodes. - pub index: usize, - - /// The WebRender spatial id of this scroll tree node. - pub spatial_id: SpatialId, -} - -/// Data stored for nodes in the [ScrollTree] that actually scroll, -/// as opposed to reference frames and sticky nodes which do not. -#[derive(Debug, Deserialize, Serialize)] -pub struct ScrollableNodeInfo { - /// The external scroll id of this node, used to track - /// it between successive re-layouts. - pub external_id: ExternalScrollId, - - /// Amount that this `ScrollableNode` can scroll in both directions. - pub scrollable_size: LayoutSize, - - /// Whether this `ScrollableNode` is sensitive to input events. - pub scroll_sensitivity: ScrollSensitivity, - - /// The current offset of this scroll node. - pub offset: LayoutVector2D, -} - -#[derive(Debug, Deserialize, Serialize)] -/// A node in a tree of scroll nodes. This may either be a scrollable -/// node which responds to scroll events or a non-scrollable one. -pub struct ScrollTreeNode { - /// The index of the parent of this node in the tree. If this is - /// None then this is the root node. - pub parent: Option<ScrollTreeNodeId>, - - /// Scrolling data which will not be None if this is a scrolling node. - pub scroll_info: Option<ScrollableNodeInfo>, -} - -impl ScrollTreeNode { - /// Get the external id of this node. - pub fn external_id(&self) -> Option<ExternalScrollId> { - self.scroll_info.as_ref().map(|info| info.external_id) - } - - /// Get the offset id of this node if it applies. - pub fn offset(&self) -> Option<LayoutVector2D> { - self.scroll_info.as_ref().map(|info| info.offset) - } - - /// Set the offset for this node, returns false if this was a - /// non-scrolling node for which you cannot set the offset. - pub fn set_offset(&mut self, new_offset: LayoutVector2D) -> bool { - match self.scroll_info { - Some(ref mut info) => { - info.offset = new_offset; - true - }, - _ => false, - } - } - - /// Scroll this node given a WebRender ScrollLocation. Returns a tuple that can - /// be used to scroll an individual WebRender scroll frame if the operation - /// actually changed an offset. - pub fn scroll( - &mut self, - scroll_location: ScrollLocation, - ) -> Option<(ExternalScrollId, LayoutVector2D)> { - let info = match self.scroll_info { - Some(ref mut data) => data, - None => return None, - }; - - if info.scroll_sensitivity != ScrollSensitivity::ScriptAndInputEvents { - return None; - } - - let delta = match scroll_location { - ScrollLocation::Delta(delta) => delta, - ScrollLocation::Start => { - if info.offset.y.round() >= 0.0 { - // Nothing to do on this layer. - return None; - } - - info.offset.y = 0.0; - return Some((info.external_id, info.offset)); - }, - ScrollLocation::End => { - let end_pos = -info.scrollable_size.height; - if info.offset.y.round() <= end_pos { - // Nothing to do on this layer. - return None; - } - - info.offset.y = end_pos; - return Some((info.external_id, info.offset)); - }, - }; - - let scrollable_width = info.scrollable_size.width; - let scrollable_height = info.scrollable_size.height; - let original_layer_scroll_offset = info.offset; - - if scrollable_width > 0. { - info.offset.x = (info.offset.x + delta.x).min(0.0).max(-scrollable_width); - } - - if scrollable_height > 0. { - info.offset.y = (info.offset.y + delta.y).min(0.0).max(-scrollable_height); - } - - if info.offset != original_layer_scroll_offset { - Some((info.external_id, info.offset)) - } else { - None - } - } -} - -/// A tree of spatial nodes, which mirrors the spatial nodes in the WebRender -/// display list, except these are used to scrolling in the compositor so that -/// new offsets can be sent to WebRender. -#[derive(Debug, Default, Deserialize, Serialize)] -pub struct ScrollTree { - /// A list of compositor-side scroll nodes that describe the tree - /// of WebRender spatial nodes, used by the compositor to scroll the - /// contents of the display list. - pub nodes: Vec<ScrollTreeNode>, -} - -impl ScrollTree { - /// Add a scroll node to this ScrollTree returning the id of the new node. - pub fn add_scroll_tree_node( - &mut self, - parent: Option<&ScrollTreeNodeId>, - spatial_id: SpatialId, - scroll_info: Option<ScrollableNodeInfo>, - ) -> ScrollTreeNodeId { - self.nodes.push(ScrollTreeNode { - parent: parent.cloned(), - scroll_info, - }); - ScrollTreeNodeId { - index: self.nodes.len() - 1, - spatial_id, - } - } - - /// Get a mutable reference to the node with the given index. - pub fn get_node_mut(&mut self, id: &ScrollTreeNodeId) -> &mut ScrollTreeNode { - &mut self.nodes[id.index] - } - - /// Get an immutable reference to the node with the given index. - pub fn get_node(&mut self, id: &ScrollTreeNodeId) -> &ScrollTreeNode { - &self.nodes[id.index] - } - - /// Scroll the given scroll node on this scroll tree. If the node cannot be scrolled, - /// because it isn't a scrollable node or it's already scrolled to the maximum scroll - /// extent, try to scroll an ancestor of this node. Returns the node scrolled and the - /// new offset if a scroll was performed, otherwise returns None. - pub fn scroll_node_or_ancestor( - &mut self, - scroll_node_id: &ScrollTreeNodeId, - scroll_location: ScrollLocation, - ) -> Option<(ExternalScrollId, LayoutVector2D)> { - let parent = { - let node = &mut self.get_node_mut(scroll_node_id); - let result = node.scroll(scroll_location); - if result.is_some() { - return result; - } - node.parent - }; - - parent.and_then(|parent| self.scroll_node_or_ancestor(&parent, scroll_location)) - } - - /// Given an [`ExternalScrollId`] and an offset, update the scroll offset of the scroll node - /// with the given id. - pub fn set_scroll_offsets_for_node_with_external_scroll_id( - &mut self, - external_scroll_id: ExternalScrollId, - offset: LayoutVector2D, - ) -> bool { - for node in self.nodes.iter_mut() { - match node.scroll_info { - Some(ref mut scroll_info) if scroll_info.external_id == external_scroll_id => { - scroll_info.offset = offset; - return true; - }, - _ => {}, - } - } - false - } -} - -/// A data structure which stores compositor-side information about -/// display lists sent to the compositor. -#[derive(Debug, Deserialize, Serialize)] -pub struct CompositorDisplayListInfo { - /// The WebRender [PipelineId] of this display list. - pub pipeline_id: PipelineId, - - /// The size of the viewport that this display list renders into. - pub viewport_size: LayoutSize, - - /// The size of this display list's content. - pub content_size: LayoutSize, - - /// The epoch of the display list. - pub epoch: Epoch, - - /// An array of `HitTestInfo` which is used to store information - /// to assist the compositor to take various actions (set the cursor, - /// scroll without layout) using a WebRender hit test result. - pub hit_test_info: Vec<HitTestInfo>, - - /// A ScrollTree used by the compositor to scroll the contents of the - /// display list. - pub scroll_tree: ScrollTree, - - /// The `ScrollTreeNodeId` of the root reference frame of this info's scroll - /// tree. - pub root_reference_frame_id: ScrollTreeNodeId, - - /// The `ScrollTreeNodeId` of the topmost scrolling frame of this info's scroll - /// tree. - pub root_scroll_node_id: ScrollTreeNodeId, -} - -impl CompositorDisplayListInfo { - /// Create a new CompositorDisplayListInfo with the root reference frame - /// and scroll frame already added to the scroll tree. - pub fn new( - viewport_size: LayoutSize, - content_size: LayoutSize, - pipeline_id: PipelineId, - epoch: Epoch, - root_scroll_sensitivity: ScrollSensitivity, - ) -> Self { - let mut scroll_tree = ScrollTree::default(); - let root_reference_frame_id = scroll_tree.add_scroll_tree_node( - None, - SpatialId::root_reference_frame(pipeline_id), - None, - ); - let root_scroll_node_id = scroll_tree.add_scroll_tree_node( - Some(&root_reference_frame_id), - SpatialId::root_scroll_node(pipeline_id), - Some(ScrollableNodeInfo { - external_id: ExternalScrollId(0, pipeline_id), - scrollable_size: content_size - viewport_size, - scroll_sensitivity: root_scroll_sensitivity, - offset: LayoutVector2D::zero(), - }), - ); - - CompositorDisplayListInfo { - pipeline_id, - viewport_size, - content_size, - epoch, - hit_test_info: Default::default(), - scroll_tree, - root_reference_frame_id, - root_scroll_node_id, - } - } - - /// Add or re-use a duplicate HitTestInfo entry in this `CompositorHitTestInfo` - /// and return the index. - pub fn add_hit_test_info( - &mut self, - node: u64, - cursor: Option<Cursor>, - scroll_tree_node: ScrollTreeNodeId, - ) -> usize { - if let Some(last) = self.hit_test_info.last() { - if node == last.node && cursor == last.cursor { - return self.hit_test_info.len() - 1; - } - } - - self.hit_test_info.push(HitTestInfo { - node, - cursor, - scroll_tree_node, - }); - self.hit_test_info.len() - 1 - } -} |