From 5a2d982d0441ae799e7a78e0bd5ce3257ff2a95d Mon Sep 17 00:00:00 2001
From: Elena Torro <elenatorro@gmail.com>
Date: Mon, 4 May 2026 17:48:32 +0200
Subject: [PATCH] :zap: Skip grid reorder and changed-attrs walk on translation
 commits

---
 common/src/app/common/logic/shapes.cljc       | 22 ++++++++++++-------
 .../src/app/main/data/workspace/shapes.cljs   | 14 +++++++++---
 2 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/common/src/app/common/logic/shapes.cljc b/common/src/app/common/logic/shapes.cljc
index f350913987..253304de65 100644
--- a/common/src/app/common/logic/shapes.cljc
+++ b/common/src/app/common/logic/shapes.cljc
@@ -75,7 +75,7 @@
     (reduce check-shape changes mod-obj-changes)))
 
 (defn generate-update-shapes
-  [changes ids update-fn objects {:keys [attrs changed-sub-attr ignore-tree ignore-touched with-objects?]}]
+  [changes ids update-fn objects {:keys [attrs changed-sub-attr ignore-tree ignore-touched with-objects? translation?]}]
   (let [changes   (reduce
                    (fn [changes id]
                      (let [opts {:attrs attrs
@@ -86,13 +86,19 @@
                    (-> changes
                        (pcb/with-objects objects))
                    ids)
-        grid-ids (->> ids (filter (partial ctl/grid-layout? objects)))
-        changes (-> changes
-                    (pcb/update-shapes grid-ids ctl/assign-cell-positions {:with-objects? true})
-                    (pcb/reorder-grid-children ids)
-                    (cond->
-                     (not ignore-touched)
-                      (generate-unapply-tokens objects changed-sub-attr)))]
+        ;; Translation doesn't shift children between grid cells, so
+        ;; cell reassignment + child reorder are no-ops with a per-grid
+        ;; cost. Skipping them on translation-only commits removes the
+        ;; grid-layout reflow from the on-drop hot path.
+        grid-ids (when-not translation?
+                   (->> ids (filter (partial ctl/grid-layout? objects))))
+        changes (cond-> changes
+                  (seq grid-ids)
+                  (-> (pcb/update-shapes grid-ids ctl/assign-cell-positions {:with-objects? true})
+                      (pcb/reorder-grid-children ids))
+
+                  (not ignore-touched)
+                  (generate-unapply-tokens objects changed-sub-attr))]
     changes))
 
 (defn- generate-update-shape-flags
diff --git a/frontend/src/app/main/data/workspace/shapes.cljs b/frontend/src/app/main/data/workspace/shapes.cljs
index dbfc1291c9..a3e6bcb8d0 100644
--- a/frontend/src/app/main/data/workspace/shapes.cljs
+++ b/frontend/src/app/main/data/workspace/shapes.cljs
@@ -73,9 +73,16 @@
               (filter #(some update-layout-attr? (pcb/changed-attrs % objects update-fn {:attrs attrs :with-objects? with-objects?})))
               (map :id))
 
+             ;; `xf-update-layout` runs `update-fn` + attr diff for
+             ;; every id just to decide whether to dispatch
+             ;; `:layout/update`. `update-layout-attr?` is `#{:hidden}`,
+             ;; so a pure-translation commit can never trigger it —
+             ;; skip the N×diff walk on drop-of-layout-drag (the hot
+             ;; on-drop path for layouts with many children).
              update-layout-ids
-             (->> (into [] xf-update-layout ids)
-                  (not-empty))
+             (when-not translation?
+               (->> (into [] xf-update-layout ids)
+                    (not-empty)))
 
              changes
              (-> (pcb/empty-changes it page-id)
@@ -88,7 +95,8 @@
                                               :changed-sub-attr changed-sub-attr
                                               :ignore-tree ignore-tree
                                               :ignore-touched ignore-touched
-                                              :with-objects? with-objects?})
+                                              :with-objects? with-objects?
+                                              :translation? translation?})
                  (cond-> undo-group
                    (pcb/set-undo-group undo-group))
                  (pcb/set-translation? translation?))