A unit of execution in a process. A unit of execution in a process. Can run methods on [Object]s simultaneously. The use of synchronization via [Mutex] or [Semaphore] is advised if working with shared objects. [b]Note:[/b] Breakpoints won't break on code if it's running in a thread. This is a current limitation of the GDScript debugger. $DOCS_URL/tutorials/performance/threads/using_multiple_threads.html $DOCS_URL/tutorials/performance/threads/thread_safe_apis.html https://godotengine.org/asset-library/asset/676 Returns the current [Thread]'s ID, uniquely identifying it among all threads. If the [Thread] is not running this returns an empty string. Returns [code]true[/code] if this [Thread] has been started. Once started, this will return [code]true[/code] until it is joined using [method wait_to_finish]. For checking if a [Thread] is still executing its task, use [method is_alive]. Returns [code]true[/code] if this [Thread] is currently running. This is useful for determining if [method wait_to_finish] can be called without blocking the calling thread. To check if a [Thread] is joinable, use [method is_active]. Starts a new [Thread] that runs [code]method[/code] on object [code]instance[/code] with [code]userdata[/code] passed as an argument. Even if no userdata is passed, [code]method[/code] must accept one argument and it will be null. The [code]priority[/code] of the [Thread] can be changed by passing a value from the [enum Priority] enum. Returns [constant OK] on success, or [constant ERR_CANT_CREATE] on failure. Joins the [Thread] and waits for it to finish. Returns the output of the method passed to [method start]. Should either be used when you want to retrieve the value returned from the method called by the [Thread] or before freeing the instance that contains the [Thread]. To determine if this can be called without blocking the calling thread, check if [method is_alive] is [code]false[/code]. [b]Note:[/b] After the [Thread] finishes joining it will be disposed. If you want to use it again you will have to create a new instance of it. A thread running with lower priority than normally. A thread with a standard priority. A thread running with higher priority than normally.