from __future__ import annotations import queue import sys import threading from typing import TYPE_CHECKING, Any, Callable from pyglet import app, clock, event if TYPE_CHECKING: from pyglet.event import EventDispatcher from pyglet.window import BaseWindow _is_pyglet_doc_run = hasattr(sys, "is_pyglet_doc_run") and sys.is_pyglet_doc_run class PlatformEventLoop: """Abstract class, implementation depends on platform. .. versionadded:: 1.2 """ def __init__(self) -> None: # noqa: D107 self._event_queue = queue.Queue() self._is_running = threading.Event() def is_running(self) -> bool: """If the event loop is currently processing. ``True`` if running, or ``False`` if it is blocked or not activated. """ return self._is_running.is_set() def post_event(self, dispatcher: EventDispatcher, event: str, *args: Any) -> None: """Post an event into the main application thread. The event is queued internally until the :py:meth:`run` method's thread is able to dispatch the event. This method can be safely called from any thread. If the method is called from the :py:meth:`run` method's thread (for example, from within an event handler), the event may be dispatched within the same runloop iteration or the next one; the choice is nondeterministic. """ self._event_queue.put((dispatcher, event, args)) self.notify() def dispatch_posted_events(self) -> None: """Immediately dispatch all pending events. Normally this is called automatically by the runloop iteration. """ while True: try: dispatcher, evnt, args = self._event_queue.get(False) dispatcher.dispatch_event(evnt, *args) except queue.Empty: break except ReferenceError: # weakly-referenced object no longer exists pass def notify(self) -> None: """Notify the event loop that something needs processing. If the event loop is blocked, it will unblock and perform an iteration immediately. If the event loop is running, another iteration is scheduled for immediate execution afterward. """ raise NotImplementedError('abstract') def start(self) -> None: pass def step(self, timeout: None | float = None) -> None: raise NotImplementedError('abstract') def set_timer(self, func: Callable, interval: float) -> None: pass def stop(self) -> None: pass class EventLoop(event.EventDispatcher): """The main run loop of the application. Calling `run` begins the application event loop, which processes operating system events, calls :py:func:`pyglet.clock.tick` to call scheduled functions and calls :py:meth:`pyglet.window.Window.on_draw` and :py:meth:`pyglet.window.Window.flip` to update window contents. Applications can subclass :py:class:`EventLoop` and override certain methods to integrate another framework's run loop, or to customise processing in some other way. You should not in general override :py:meth:`run`, as this method contains platform-specific code that ensures the application remains responsive to the user while keeping CPU usage to a minimum. """ _has_exit_condition = None _has_exit = False def __init__(self) -> None: # noqa: D107 self._has_exit_condition = threading.Condition() self.clock = clock.get_default() self.is_running = False self._interval = None @staticmethod def _redraw_windows(dt: float) -> None: # Redraw all windows for window in app.windows: window.draw(dt) def run(self, interval: float | None = 1/60) -> None: """Begin processing events, scheduled functions and window updates. This method enters into the main event loop and, if the ``interval`` argument is not changed, schedules calling the :py:meth:`pyglet.window.Window.draw` method. You can change the ``interval`` argument to suit your needs. Args: interval: Windows redraw interval, in seconds (framerate). If ``interval == 0``, windows will redraw as fast as possible. This can saturate a CPU core, so do not do this unless GPU bound. If ``interval is None``, pyglet will not schedule calls to the :py:meth:`pyglet.window.Window.draw` method. Users must schedule this themselves for each Window (or call it on-demand). This allows setting a custom framerate per window, or changing framerate during runtime (see example in the documentation). This method returns when :py:attr:`has_exit` is set to True. IE: when :py:meth:`exit` is called. Developers are discouraged from overriding the ``run`` method, as the implementation is platform-specific. """ self._interval = interval if interval is None: # User must call Window.draw() themselves. pass elif interval == 0: self.clock.schedule(self._redraw_windows) else: self.clock.schedule_interval(self._redraw_windows, interval) self.has_exit = False from pyglet.window import Window Window._enable_event_queue = False # Dispatch pending events for window in app.windows: window.switch_to() window.dispatch_pending_events() platform_event_loop = app.platform_event_loop platform_event_loop.start() self.dispatch_event('on_enter') self.is_running = True while not self.has_exit: timeout = self.idle() platform_event_loop.step(timeout) self.is_running = False self.dispatch_event('on_exit') platform_event_loop.stop() def enter_blocking(self) -> None: """Called by pyglet internal processes when the operating system is about to block due to a user interaction. For example, this is common when the user begins resizing or moving a window. This method provides the event loop with an opportunity to set up an OS timer on the platform event loop, which will continue to be invoked during the blocking operation. The default implementation ensures that :py:meth:`idle` continues to be called as documented. .. versionadded:: 1.2 """ timeout = self.idle() app.platform_event_loop.set_timer(self._blocking_timer, timeout) @staticmethod def exit_blocking() -> None: """Called by pyglet internal processes when the blocking operation completes. :see: :py:meth:`enter_blocking`. """ app.platform_event_loop.set_timer(None, None) def _blocking_timer(self) -> None: dt = self.clock.update_time() self.clock.call_scheduled_functions(dt) if self._interval is None: self._redraw_windows(dt) # Update timout timeout = self.clock.get_sleep_time(True) app.platform_event_loop.set_timer(self._blocking_timer, timeout) def idle(self) -> None | float: """Called during each iteration of the event loop. The method is called immediately after any window events (i.e., after any user input). The method can return a duration after which the idle method will be called again. The method may be called earlier if the user creates more input events. The method can return `None` to only wait for user events. For example, return ``1.0`` to have the idle method called every second, or immediately after any user events. The default implementation dispatches the :py:meth:`pyglet.window.Window.on_draw` event for all windows and uses :py:func:`pyglet.clock.tick` and :py:func:`pyglet.clock.get_sleep_time` on the default clock to determine the return value. This method should be overridden by advanced users only. To have code execute at regular intervals, use the :py:func:`pyglet.clock.schedule` methods. Returns: The number of seconds before the idle method should be called again, or ``None`` to block for user input. """ dt = self.clock.update_time() self.clock.call_scheduled_functions(dt) # Update timout return self.clock.get_sleep_time(True) @property def has_exit(self) -> bool: """Flag indicating if the event loop will exit in the next iteration. When set, all waiting threads are interrupted. :see :py:meth:`sleep`: Thread-safe since pyglet 1.2. """ self._has_exit_condition.acquire() result = self._has_exit self._has_exit_condition.release() return result @has_exit.setter def has_exit(self, value: bool) -> None: self._has_exit_condition.acquire() self._has_exit = value self._has_exit_condition.notify() self._has_exit_condition.release() def exit(self) -> None: """Safely exit the event loop at the end of the current iteration. This method is a thread-safe equivalent for setting :py:attr:`has_exit` to ``True``. All waiting threads will be interrupted (see :py:meth:`sleep`). """ self.has_exit = True app.platform_event_loop.notify() def sleep(self, timeout: float) -> bool: """Wait for some amount of time. Waits until the :py:attr:`has_exit` flag is set or :py:meth:`exit` is called. This method is thread-safe. Args: timeout: Time to sleep, in seconds. .. versionadded:: 1.2 """ self._has_exit_condition.acquire() self._has_exit_condition.wait(timeout) result = self._has_exit self._has_exit_condition.release() return result def on_window_close(self, window: BaseWindow) -> None: """Default window close handler.""" if len(app.windows) == 0: self.exit() if _is_pyglet_doc_run: # Events def on_window_close(self, window: BaseWindow) -> None: """A window was closed. This event is dispatched when a window is closed. It is not dispatched if the window's close button was pressed but the window did not close. The default handler calls :py:meth:`exit` if no more windows are open. You can override this handler to base your application exit on some other policy. """ def on_enter(self) -> None: """The event loop is about to begin. This is dispatched when the event loop is prepared to enter the main run loop, and represents the last chance for an application to initialise itself. """ def on_exit(self) -> None: """The event loop is about to exit. After dispatching this event, the :py:meth:`run` method returns (the application may not actually exit if you have more code following the :py:meth:`run` invocation). """ EventLoop.register_event_type('on_window_close') EventLoop.register_event_type('on_enter') EventLoop.register_event_type('on_exit')