From 5a3c7b41d8ca61524431c0b743ced942f6df704d Mon Sep 17 00:00:00 2001
From: kobewi <kobewi4e@gmail.com>
Date: Tue, 25 Jun 2024 22:49:36 +0200
Subject: [PATCH] Optimize get_path() in EditorFileSystemDirectory

---
 editor/editor_file_system.cpp | 38 ++++++++++++++++++++++-------------
 1 file changed, 24 insertions(+), 14 deletions(-)

diff --git a/editor/editor_file_system.cpp b/editor/editor_file_system.cpp
index d84ccb0c03c..95d64618f5c 100644
--- a/editor/editor_file_system.cpp
+++ b/editor/editor_file_system.cpp
@@ -94,25 +94,35 @@ String EditorFileSystemDirectory::get_file(int p_idx) const {
 }
 
 String EditorFileSystemDirectory::get_path() const {
-	String p;
-	const EditorFileSystemDirectory *d = this;
-	while (d->parent) {
-		p = d->name.path_join(p);
-		d = d->parent;
+	int parents = 0;
+	const EditorFileSystemDirectory *efd = this;
+	// Determine the level of nesting.
+	while (efd->parent) {
+		parents++;
+		efd = efd->parent;
 	}
 
-	return "res://" + p;
+	if (parents == 0) {
+		return "res://";
+	}
+
+	// Using PackedStringArray, because the path is built in reverse order.
+	PackedStringArray path_bits;
+	// Allocate an array based on nesting. It will store path bits.
+	path_bits.resize(parents + 2); // Last String is empty, so paths end with /.
+	String *path_write = path_bits.ptrw();
+	path_write[0] = "res:/";
+
+	efd = this;
+	for (int i = parents; i > 0; i--) {
+		path_write[i] = efd->name;
+		efd = efd->parent;
+	}
+	return String("/").join(path_bits);
 }
 
 String EditorFileSystemDirectory::get_file_path(int p_idx) const {
-	String file = get_file(p_idx);
-	const EditorFileSystemDirectory *d = this;
-	while (d->parent) {
-		file = d->name.path_join(file);
-		d = d->parent;
-	}
-
-	return "res://" + file;
+	return get_path().path_join(get_file(p_idx));
 }
 
 Vector<String> EditorFileSystemDirectory::get_file_deps(int p_idx) const {