.. index:: pair: class; EE::Scene::MainThreadExecutor
.. _doxid-class_e_e_1_1_scene_1_1_main_thread_executor:

class EE::Scene::MainThreadExecutor
===================================

.. toctree::
	:hidden:

Overview
~~~~~~~~

:ref:`Executor <doxid-class_e_e_1_1_executor>` that runs functions on the main (:ref:`UI <doxid-namespace_e_e_1_1_u_i>`) thread. :ref:`More...<details-class_e_e_1_1_scene_1_1_main_thread_executor>`


.. ref-code-block:: cpp
	:class: doxyrest-overview-code-block

	#include <mainthreadexecutor.hpp>
	
	class MainThreadExecutor: public :ref:`EE::Executor<doxid-class_e_e_1_1_executor>` {
	public:
		// construction
	
		:target:`MainThreadExecutor<doxid-class_e_e_1_1_scene_1_1_main_thread_executor_1accba347cc694edbb9b8cb14523418478>`(:ref:`Node<doxid-class_e_e_1_1_scene_1_1_node>`* dispatcher);
		:target:`MainThreadExecutor<doxid-class_e_e_1_1_scene_1_1_main_thread_executor_1a05474743a036c73a6ffe163dc7655042>`(const MainThreadExecutor&);
		:target:`~MainThreadExecutor<doxid-class_e_e_1_1_scene_1_1_main_thread_executor_1a5e7d861dda412d8237db23e49abf8e0f>`();

		// methods
	
		MainThreadExecutor& :target:`operator=<doxid-class_e_e_1_1_scene_1_1_main_thread_executor_1acd9df2a7fea18811dd0e7179f7f797bf>`(const MainThreadExecutor&);
		virtual void :target:`execute<doxid-class_e_e_1_1_scene_1_1_main_thread_executor_1a732d4a5ddab6092392f126c833027801>`(:ref:`Function<doxid-class_e_e_1_1_executor_1ae17f637b77d7f53e8e5157f6fd2357ca>` function);
		void :ref:`shutdown<doxid-class_e_e_1_1_scene_1_1_main_thread_executor_1aa22ebad83ffd478559f461afa1ebc46f>`();
		size_t :ref:`pending<doxid-class_e_e_1_1_scene_1_1_main_thread_executor_1a3e24f5b4207c827e9d6b3f53acd6b739>`() const;
	};

Inherited Members
-----------------

.. ref-code-block:: cpp
	:class: doxyrest-overview-inherited-code-block

	public:
		// typedefs
	
		typedef :ref:`SmallUniqueFunction<doxid-class_e_e_1_1_small_unique_function>`<void(), :ref:`FunctionInlineSize<doxid-class_e_e_1_1_executor_1a412519a6d5b5d9c225c995a573cf4544>`> :ref:`Function<doxid-class_e_e_1_1_executor_1ae17f637b77d7f53e8e5157f6fd2357ca>`;

		// fields
	
		static constexpr std::size_t :ref:`FunctionInlineSize<doxid-class_e_e_1_1_executor_1a412519a6d5b5d9c225c995a573cf4544>` = 64;

		// methods
	
		virtual void :ref:`execute<doxid-class_e_e_1_1_executor_1ae3b0983ac5b467a6cfe604615e9fefb8>`(:ref:`Function<doxid-class_e_e_1_1_executor_1ae17f637b77d7f53e8e5157f6fd2357ca>` function) = 0;

.. _details-class_e_e_1_1_scene_1_1_main_thread_executor:

Detailed Documentation
~~~~~~~~~~~~~~~~~~~~~~

:ref:`Executor <doxid-class_e_e_1_1_executor>` that runs functions on the main (:ref:`UI <doxid-namespace_e_e_1_1_u_i>`) thread.

Functions are queued and drained in submission order by a single :ref:`Node::runOnMainThread() <doxid-class_e_e_1_1_scene_1_1_node_1ab5490ad555d2fa97bdb45c66b46a2fa0>` runnable per batch, so bursts of continuations cost one scheduled action. Execution is always deferred to the next scene update, even when :ref:`execute() <doxid-class_e_e_1_1_scene_1_1_main_thread_executor_1a732d4a5ddab6092392f126c833027801>` is called from the main thread, which is what :ref:`Task::then() <doxid-class_e_e_1_1_task_1afd1872c589904c3ec68dba689a6eb4a6>` requires.

The dispatcher node must outlive the executor, or :ref:`shutdown() <doxid-class_e_e_1_1_scene_1_1_main_thread_executor_1aa22ebad83ffd478559f461afa1ebc46f>` must be called before the node is destroyed. Destroying the executor drops queued functions that have not run yet (releasing what they own, for example abandoning the tasks of the resolvers they hold).

Methods
-------

.. index:: pair: function; shutdown
.. _doxid-class_e_e_1_1_scene_1_1_main_thread_executor_1aa22ebad83ffd478559f461afa1ebc46f:

.. ref-code-block:: cpp
	:class: doxyrest-title-code-block

	void shutdown()

Detaches the executor from its dispatcher node and drops the queued functions. Functions executed afterwards are dropped too. Call it before the dispatcher node is destroyed when work may still be executed on this executor (it must then outlive that work).

.. index:: pair: function; pending
.. _doxid-class_e_e_1_1_scene_1_1_main_thread_executor_1a3e24f5b4207c827e9d6b3f53acd6b739:

.. ref-code-block:: cpp
	:class: doxyrest-title-code-block

	size_t pending() const



.. rubric:: Returns:

Number of functions waiting for the main thread.