tree: Node Depth

CHANGES.md

@@ -48,6 +48,9 @@ package called `cetz-plot`.
 ## Util
 - `apply-transform` now allows passing a function that takes and returns a vector, instead of a transformation matrix.
 
+## Tree
+- Support specifying an items depth by setting the first data-value to an integer.
+
 # 0.2.2
 
 ## Anchors

src/lib/tree.typ

@@ -131,12 +131,20 @@
   }
   assert(draw-node != none, message: "Node draw callback must be set!")
 
-  let build-node(tree, depth: 0, sibling: 0) = {
+  let build-node(tree-arr, depth: 0, sibling: 0) = {
     let children = ()
     let content = none
+
+    let (e, tree) = if type(tree-arr) == array and tree-arr.len() == 2 and type(tree-arr.at(0)) in (int,float) {
+        tree-arr
+    } else {
+        (1, tree-arr)
+    }
+    let depth = depth + e
+
     if type(tree) == array {
       children = tree.slice(1).enumerate().map(
-        ((n, c)) => build-node(c, depth: depth + 1, sibling: n)
+        ((n, c)) => build-node(c, depth: depth, sibling: n)
       )
       content = tree.at(0)
     } else {

tests/tree/test.typ

@@ -42,3 +42,9 @@
   })
   h(.1cm)
 }
+
+// Specify branch lengths
+#test-case({
+  cetz.draw.set-style(content: (frame: "rect", padding: .1))
+  cetz.tree.tree(([A], (1, ([B], (1, [C]), (1, [D]))), (2, [E])))
+})