mirror of
https://github.com/servo/servo.git
synced 2025-08-06 06:00:15 +01:00
layout: Avoid layout sometimes when stretching (#33967)
This is the second flexbox caching change. It seeks to detect when a relayout can be avoided in the case of a stretching flex item. This heuristic can be combined, because currently we still do relayout sometimes when we do not need to. For instance currently we always relayout when a flex child is itself a column flex. This only needs to happen when the grandchildren themselves grow or shrink. That optimization is perhaps a lower priority as `flex-grow: 0 / flex-shrink: 1` is the default behavior for flex. Since this change means we more consistenly zero out the percentage part of `calc` expressions when they have circular dependencies, this causes one test to start failing (`/css/css-values/calc-min-height-block-1.html`). This is related to w3c/csswg-drafts#10969, which is pending on further discussion in the working group. Signed-off-by: Martin Robinson <mrobinson@igalia.com> Co-authored-by: Oriol Brufau <obrufau@igalia.com>
This commit is contained in:
parent
638b520186
commit
52db185568
12 changed files with 490 additions and 257 deletions
|
@ -117,7 +117,7 @@ pub(crate) enum FlexLevelBox {
|
|||
pub(crate) struct FlexItemBox {
|
||||
independent_formatting_context: IndependentFormattingContext,
|
||||
#[serde(skip)]
|
||||
cached_layout: ArcRefCell<Option<FlexItemLayoutCache>>,
|
||||
block_content_size_cache: ArcRefCell<Option<CachedBlockSizeContribution>>,
|
||||
}
|
||||
|
||||
impl std::fmt::Debug for FlexItemBox {
|
||||
|
@ -136,19 +136,7 @@ impl FlexItemBox {
|
|||
}
|
||||
}
|
||||
|
||||
#[derive(Debug)]
|
||||
struct FlexItemLayoutCacheDescriptor {
|
||||
struct CachedBlockSizeContribution {
|
||||
containing_block_inline_size: Au,
|
||||
content_block_size: Au,
|
||||
}
|
||||
|
||||
impl FlexItemLayoutCacheDescriptor {
|
||||
fn compatible_with_size(&self, inline: Au) -> bool {
|
||||
inline == self.containing_block_inline_size
|
||||
}
|
||||
}
|
||||
|
||||
/// A cache to avoid multiple layouts during flexbox layout.
|
||||
struct FlexItemLayoutCache {
|
||||
descriptor: FlexItemLayoutCacheDescriptor,
|
||||
}
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue