Struct ScrollTreeNode

pub struct ScrollTreeNode {
    pub parent: Option<ScrollTreeNodeId>,
    pub children: Vec<ScrollTreeNodeId>,
    pub webrender_id: Option<SpatialId>,
    pub info: SpatialTreeNodeInfo,
    transformation_cache: Cell<Option<ScrollTreeNodeTransformationCache>>,
}

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.

Fields

parent: Option<ScrollTreeNodeId>

The index of the parent of this node in the tree. If this is None then this is the root node.

children: Vec<ScrollTreeNodeId>

The children of this ScrollTreeNode.

webrender_id: Option<SpatialId>

The WebRender id, which is filled in when this tree is serialiezd into a WebRender display list.

info: SpatialTreeNodeInfo

Specific information about this node, depending on whether it is a scroll node or a reference frame.

transformation_cache: Cell<Option<ScrollTreeNodeTransformationCache>>

Cached transformation information that’s used to do things like hit testing and viewport bounding box calculation.

Implementations

impl ScrollTreeNode

pub fn webrender_id(&self) -> SpatialId

Get the WebRender SpatialId for the given [ScrollNodeId]. This will panic if [ScrollTree::build_display_list] has not been called yet.

pub fn external_id(&self) -> Option<ExternalScrollId>

Get the external id of this node.

pub fn offset(&self) -> Option<LayoutVector2D>

Get the offset id of this node if it applies.

fn scroll( &mut self, scroll_location: ScrollLocation, context: ScrollType, ) -> Option<(ExternalScrollId, LayoutVector2D)>

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 debug_print(&self, print_tree: &mut PrintTree, node_index: usize)

fn invalidate_cached_transforms( &self, scroll_tree: &ScrollTree, ancestors_invalid: bool, )

Trait Implementations

impl Debug for ScrollTreeNode

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ScrollTreeNode

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl MallocSizeOf for ScrollTreeNode

fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize

Measure the heap usage of all descendant heap-allocated structures, but not the space taken up by the value itself.

impl Serialize for ScrollTreeNode

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.