Struct layout_2020::flow::BoxTree

pub struct BoxTree {
    root: BlockFormattingContext,
    canvas_background: CanvasBackground,
    sensitive_to_scroll_input: bool,
}

Fields

root: BlockFormattingContext

Contains typically exactly one block-level box, which was generated by the root element. There may be zero if that element has display: none.

canvas_background: CanvasBackground

https://drafts.csswg.org/css-backgrounds/#special-backgrounds

sensitive_to_scroll_input: bool

Whether or not the root element should be sensitive to scrolling input events.

Implementations

impl BoxTree

pub fn construct<'dom, Node>( context: &LayoutContext<'_>, root_element: Node, ) -> Self

where Node: 'dom + Copy + LayoutNode<'dom> + Send + Sync,

pub fn update<'dom, Node>(context: &LayoutContext<'_>, dirty_node: Node) -> bool

where Node: 'dom + Copy + LayoutNode<'dom> + Send + Sync,

This method attempts to incrementally update the box tree from an arbitrary node that is not necessarily the document’s root element.

If the node is not a valid candidate for incremental update, the method loops over its parent. The only valid candidates for now are absolutely positioned boxes which don’t change their outside display mode (i.e. it will not attempt to update from an absolutely positioned inline element which became an absolutely positioned block element). The value true is returned if an incremental update could be done, and false otherwise.

There are various pain points that need to be taken care of to extend the set of valid candidates:

• it is not obvious how to incrementally check whether a block formatting context still contains floats or not;
• the propagation of text decorations towards node descendants is hard to do incrementally with our current representation of boxes
• how intrinsic content sizes are computed eagerly makes it hard to update those sizes for ancestors of the node from which we made an incremental update.

impl BoxTree

pub fn layout( &self, layout_context: &LayoutContext<'_>, viewport: Size2D<f32, CSSPixel>, ) -> FragmentTree

Trait Implementations

impl Serialize for BoxTree

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

where __S: Serializer,

Serialize this value into the given Serde serializer.