Use taffy to retrieve the parent for a given layout node

Cargo.lock

@@ -3091,9 +3091,9 @@ dependencies = [
 
 [[package]]
 name = "grid"
-version = "0.11.0"
+version = "0.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1df00eed8d1f0db937f6be10e46e8072b0671accb504cf0f959c5c52c679f5b9"
+checksum = "d196ffc1627db18a531359249b2bf8416178d84b729f3cebeb278f285fb9b58c"
 
 [[package]]
 name = "h2"
@@ -7665,11 +7665,12 @@ dependencies = [
 [[package]]
 name = "taffy"
 version = "0.3.11"
-source = "git+https://github.com/DioxusLabs/taffy?rev=1876f72bee5e376023eaa518aa7b8a34c769bd1b#1876f72bee5e376023eaa518aa7b8a34c769bd1b"
+source = "git+https://github.com/zed-industries/taffy?rev=5e6c2d23e70e9f2156911d11050cb686362ba277#5e6c2d23e70e9f2156911d11050cb686362ba277"
 dependencies = [
  "arrayvec 0.7.4",
  "grid",
  "num-traits",
+ "serde",
  "slotmap",
 ]
 

crates/gpui/Cargo.toml

@@ -46,7 +46,7 @@ serde_derive.workspace = true
 serde_json.workspace = true
 smallvec.workspace = true
 smol.workspace = true
-taffy = { git = "https://github.com/DioxusLabs/taffy", rev = "1876f72bee5e376023eaa518aa7b8a34c769bd1b" }
+taffy = { git = "https://github.com/zed-industries/taffy", rev = "5e6c2d23e70e9f2156911d11050cb686362ba277" }
 thiserror.workspace = true
 time.workspace = true
 tiny-skia = "0.5"

crates/gpui/src/taffy.rs

@@ -6,15 +6,12 @@ use collections::{FxHashMap, FxHashSet};
 use smallvec::SmallVec;
 use std::fmt::Debug;
 use taffy::{
-    geometry::{Point as TaffyPoint, Rect as TaffyRect, Size as TaffySize},
+    AvailableSpace as TaffyAvailableSpace, NodeId, Point as TaffyPoint, Rect as TaffyRect,
-    style::AvailableSpace as TaffyAvailableSpace,
+    Size as TaffySize, TaffyTree, TraversePartialTree,
-    tree::NodeId,
-    Taffy,
 };
 
 pub struct TaffyLayoutEngine {
-    taffy: Taffy,
+    tree: TaffyTree,
-    children_to_parents: FxHashMap<LayoutId, LayoutId>,
     absolute_layout_bounds: FxHashMap<LayoutId, Bounds<Pixels>>,
     computed_layouts: FxHashSet<LayoutId>,
     nodes_to_measure: FxHashMap<
@@ -34,8 +31,7 @@ static EXPECT_MESSAGE: &str = "we should avoid taffy layout errors by constructi
 impl TaffyLayoutEngine {
     pub fn new() -> Self {
         TaffyLayoutEngine {
-            taffy: Taffy::new(),
+            tree: TaffyTree::new(),
-            children_to_parents: FxHashMap::default(),
             absolute_layout_bounds: FxHashMap::default(),
             computed_layouts: FxHashSet::default(),
             nodes_to_measure: FxHashMap::default(),
@@ -43,8 +39,7 @@ impl TaffyLayoutEngine {
     }
 
     pub fn clear(&mut self) {
-        self.taffy.clear();
+        self.tree.clear();
-        self.children_to_parents.clear();
         self.absolute_layout_bounds.clear();
         self.computed_layouts.clear();
         self.nodes_to_measure.clear();
@@ -58,18 +53,13 @@ impl TaffyLayoutEngine {
     ) -> LayoutId {
         let style = style.to_taffy(rem_size);
         if children.is_empty() {
-            self.taffy.new_leaf(style).expect(EXPECT_MESSAGE).into()
+            self.tree.new_leaf(style).expect(EXPECT_MESSAGE).into()
         } else {
-            let parent_id = self
+            self.tree
-                .taffy
                 // This is safe because LayoutId is repr(transparent) to taffy::tree::NodeId.
                 .new_with_children(style, unsafe { std::mem::transmute(children) })
                 .expect(EXPECT_MESSAGE)
-                .into();
+                .into()
-            for child_id in children {
-                self.children_to_parents.insert(*child_id, parent_id);
-            }
-            parent_id
         }
     }
 
@@ -83,7 +73,7 @@ impl TaffyLayoutEngine {
         let style = style.to_taffy(rem_size);
 
         let layout_id = self
-            .taffy
+            .tree
             .new_leaf_with_context(style, ())
             .expect(EXPECT_MESSAGE)
             .into();
@@ -96,7 +86,7 @@ impl TaffyLayoutEngine {
     fn count_all_children(&self, parent: LayoutId) -> anyhow::Result<u32> {
         let mut count = 0;
 
-        for child in self.taffy.children(parent.0)? {
+        for child in self.tree.children(parent.0)? {
             // Count this child.
             count += 1;
 
@@ -112,12 +102,12 @@ impl TaffyLayoutEngine {
     fn max_depth(&self, depth: u32, parent: LayoutId) -> anyhow::Result<u32> {
         println!(
             "{parent:?} at depth {depth} has {} children",
-            self.taffy.child_count(parent.0)?
+            self.tree.child_count(parent.0)
         );
 
         let mut max_child_depth = 0;
 
-        for child in self.taffy.children(parent.0)? {
+        for child in self.tree.children(parent.0)? {
             max_child_depth = std::cmp::max(max_child_depth, self.max_depth(0, LayoutId(child))?);
         }
 
@@ -129,7 +119,7 @@ impl TaffyLayoutEngine {
     fn get_edges(&self, parent: LayoutId) -> anyhow::Result<Vec<(LayoutId, LayoutId)>> {
         let mut edges = Vec::new();
 
-        for child in self.taffy.children(parent.0)? {
+        for child in self.tree.children(parent.0)? {
             edges.push((parent, LayoutId(child)));
 
             edges.extend(self.get_edges(LayoutId(child))?);
@@ -162,7 +152,7 @@ impl TaffyLayoutEngine {
             while let Some(id) = stack.pop() {
                 self.absolute_layout_bounds.remove(&id);
                 stack.extend(
-                    self.taffy
+                    self.tree
                         .children(id.into())
                         .expect(EXPECT_MESSAGE)
                         .into_iter()
@@ -172,7 +162,7 @@ impl TaffyLayoutEngine {
         }
 
         // let started_at = std::time::Instant::now();
-        self.taffy
+        self.tree
             .compute_layout_with_measure(
                 id.into(),
                 available_space.into(),
@@ -199,14 +189,14 @@ impl TaffyLayoutEngine {
             return layout;
         }
 
-        let layout = self.taffy.layout(id.into()).expect(EXPECT_MESSAGE);
+        let layout = self.tree.layout(id.into()).expect(EXPECT_MESSAGE);
         let mut bounds = Bounds {
             origin: layout.location.into(),
             size: layout.size.into(),
         };
 
-        if let Some(parent_id) = self.children_to_parents.get(&id).copied() {
+        if let Some(parent_id) = self.tree.parent(id.0) {
-            let parent_bounds = self.layout_bounds(parent_id);
+            let parent_bounds = self.layout_bounds(parent_id.into());
             bounds.origin += parent_bounds.origin;
         }
         self.absolute_layout_bounds.insert(id, bounds);