Difficult-Rocket/pyglet/app/base.py
2021-03-24 23:37:10 +08:00

348 lines
12 KiB
Python

# ----------------------------------------------------------------------------
# pyglet
# Copyright (c) 2006-2008 Alex Holkner
# Copyright (c) 2008-2020 pyglet contributors
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in
# the documentation and/or other materials provided with the
# distribution.
# * Neither the name of pyglet nor the names of its
# contributors may be used to endorse or promote products
# derived from this software without specific prior written
# permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
# ----------------------------------------------------------------------------
import sys
import queue
import platform
import threading
from pyglet import app
from pyglet import clock
from pyglet import event
from pyglet import compat_platform
_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):
self._event_queue = queue.Queue()
self._is_running = threading.Event()
self._is_running.clear()
def is_running(self):
"""Return True if the event loop is currently processing, or False
if it is blocked or not activated.
:rtype: bool
"""
return self._is_running.is_set()
def post_event(self, dispatcher, event, *args):
"""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.
:Parameters:
`dispatcher` : EventDispatcher
Dispatcher to process the event.
`event` : str
Event name.
`args` : sequence
Arguments to pass to the event handlers.
"""
self._event_queue.put((dispatcher, event, args))
self.notify()
def dispatch_posted_events(self):
"""Immediately dispatch all pending events.
Normally this is called automatically by the runloop iteration.
"""
while True:
try:
dispatcher, event, args = self._event_queue.get(False)
except queue.Empty:
break
dispatcher.dispatch_event(event, *args)
def notify(self):
"""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 afterwards.
"""
raise NotImplementedError('abstract')
def start(self):
pass
def step(self, timeout=None):
raise NotImplementedError('abstract')
def set_timer(self, func, interval):
raise NotImplementedError('abstract')
def stop(self):
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):
self._has_exit_condition = threading.Condition()
self.clock = clock.get_default()
self.is_running = False
def run(self):
"""Begin processing events, scheduled functions and window updates.
This method returns when :py:attr:`has_exit` is set to True.
Developers are discouraged from overriding this method, as the
implementation is platform-specific.
"""
self.has_exit = False
self._legacy_setup()
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 _legacy_setup(self):
# Disable event queuing for dispatch_events
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()
def enter_blocking(self):
"""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)
def exit_blocking(self):
"""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):
timeout = self.idle()
app.platform_event_loop.set_timer(self._blocking_timer, timeout)
def idle(self):
"""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.
:rtype: float
:return: The number of seconds before the idle method should
be called again, or `None` to block for user input.
"""
dt = self.clock.update_time()
redraw_all = self.clock.call_scheduled_functions(dt)
# Redraw all windows
for window in app.windows:
if redraw_all or (window._legacy_invalid and window.invalid):
window.switch_to()
window.dispatch_event('on_draw')
window.flip()
window._legacy_invalid = False
# Update timout
return self.clock.get_sleep_time(True)
@property
def has_exit(self):
"""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.
:see: `exit`
:type: bool
"""
self._has_exit_condition.acquire()
result = self._has_exit
self._has_exit_condition.release()
return result
@has_exit.setter
def has_exit(self, value):
self._has_exit_condition.acquire()
self._has_exit = value
self._has_exit_condition.notify()
self._has_exit_condition.release()
def exit(self):
"""Safely exit the event loop at the end of the current iteration.
This method is a thread-safe equivalent for 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):
"""Wait for some amount of time, or until the :py:attr:`has_exit` flag
is set or :py:meth:`exit` is called.
This method is thread-safe.
:Parameters:
`timeout` : float
Time to wait, in seconds.
.. versionadded:: 1.2
:rtype: bool
:return: ``True`` if the `has_exit` flag is set, otherwise ``False``.
"""
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):
"""Default window close handler."""
if len(app.windows) == 0:
self.exit()
if _is_pyglet_doc_run:
def on_window_close(self, window):
"""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.
:event:
"""
def on_enter(self):
"""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.
:event:
"""
def on_exit(self):
"""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).
:event:
"""
EventLoop.register_event_type('on_window_close')
EventLoop.register_event_type('on_enter')
EventLoop.register_event_type('on_exit')