From a1ae0905a39a53a0705acdac0558aa45dc898123 Mon Sep 17 00:00:00 2001
From: Victor Lin <13424970+victorlin@users.noreply.github.com>
Date: Wed, 9 Oct 2024 16:51:55 -0700
Subject: [PATCH] =?UTF-8?q?=F0=9F=9A=A7=20add=20extra=20padding=20after=20?=
 =?UTF-8?q?last=20visible=20node?=
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---
 src/components/tree/phyloTree/helpers.js | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/src/components/tree/phyloTree/helpers.js b/src/components/tree/phyloTree/helpers.js
index 5d41bde04..ca38a1775 100644
--- a/src/components/tree/phyloTree/helpers.js
+++ b/src/components/tree/phyloTree/helpers.js
@@ -115,12 +115,27 @@ function getDisplayOrderCallback(nodes, focus) {
    */
   let displayOrder = 0;
 
+  /**
+   * Keep track of whether the previous node was selected
+   */
+  let previousWasVisible;
+
   if (focus) {
-    const nSelected = nodes.filter((d) => !d.hasChildren && d.visibility === NODE_VISIBLE).length;
-    const yPerSelected = (0.8 * nodes.length) / nSelected;
-    const yPerUnselected = (0.2 * nodes.length) / (nodes.length - nSelected);
+    const numVisible = nodes.filter((d) => !d.hasChildren && d.visibility === NODE_VISIBLE).length;
+    const yPerFocused = (0.8 * nodes.length) / numVisible;
+    const yPerUnfocused = (0.2 * nodes.length) / (nodes.length - numVisible);
+
     return (node) => {
-      displayOrder += node.visibility === NODE_VISIBLE ? yPerSelected : yPerUnselected;
+      // Focus if the current node is visible or if the previous node was visible (for symmetric padding)
+      if (node.visibility === NODE_VISIBLE || previousWasVisible) {
+        displayOrder += yPerFocused;
+      } else {
+        displayOrder += yPerUnfocused;
+      }
+
+      // Update for the next node
+      previousWasVisible = node.visibility === NODE_VISIBLE;
+
       return displayOrder;
     };
   } else {