1 files changed, 26 insertions, 1 deletions

diff --git a/core/string/string_name.h b/core/string/string_name.h
index 9653d2b4cf..ff4c41af94 100644
--- a/core/string/string_name.h
+++ b/core/string/string_name.h
@@ -35,6 +35,8 @@
 #include "core/string/ustring.h"
 #include "core/templates/safe_refcount.h"
 
+#define UNIQUE_NODE_PREFIX "%"
+
 class Main;
 
 struct StaticCString {
@@ -70,7 +72,7 @@ class StringName {
 	_Data *_data = nullptr;
 
 	union _HashUnion {
-		_Data *ptr;
+		_Data *ptr = nullptr;
 		uint32_t hash;
 	};
 
@@ -100,6 +102,17 @@ public:
 	bool operator==(const String &p_name) const;
 	bool operator==(const char *p_name) const;
 	bool operator!=(const String &p_name) const;
+
+	_FORCE_INLINE_ bool is_node_unique_name() const {
+		if (!_data) {
+			return false;
+		}
+		if (_data->cname != nullptr) {
+			return (char32_t)_data->cname[0] == (char32_t)UNIQUE_NODE_PREFIX[0];
+		} else {
+			return (char32_t)_data->name[0] == (char32_t)UNIQUE_NODE_PREFIX[0];
+		}
+	}
 	_FORCE_INLINE_ bool operator<(const StringName &p_name) const {
 		return _data < p_name._data;
 	}
@@ -181,6 +194,18 @@ bool operator!=(const char *p_name, const StringName &p_string_name);
 
 StringName _scs_create(const char *p_chr, bool p_static = false);
 
+/*
+ * The SNAME macro is used to speed up StringName creation, as it allows caching it after the first usage in a very efficient way.
+ * It should NOT be used everywhere, but instead in places where high performance is required and the creation of a StringName
+ * can be costly. Places where it should be used are:
+ * - Control::get_theme_*(<name> and Window::get_theme_*(<name> functions.
+ * - emit_signal(<name>,..) function
+ * - call_deferred(<name>,..) function
+ * - Comparisons to a StringName in overridden _set and _get methods.
+ *
+ * Use in places that can be called hundreds of times per frame (or more) is recommended, but this situation is very rare. If in doubt, do not use.
+ */
+
 #define SNAME(m_arg) ([]() -> const StringName & { static StringName sname = _scs_create(m_arg, true); return sname; })()
 
 #endif // STRING_NAME_H