44 lines
868 B
Python
44 lines
868 B
Python
__all__ = ('n_frames', )
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import typing as T
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import types
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from kivy.clock import Clock
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from asyncgui import _current_task, _sleep_forever
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@types.coroutine
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def n_frames(n: int) -> T.Awaitable:
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'''
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Waits for a specified number of frames.
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.. code-block::
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await n_frames(2)
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If you want to wait for one frame, :func:`asynckivy.sleep` is preferable for a performance reason.
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.. code-block::
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await sleep(0)
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'''
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if n < 0:
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raise ValueError(f"Waiting for {n} frames doesn't make sense.")
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if not n:
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return
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task = (yield _current_task)[0][0]
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def callback(dt):
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nonlocal n
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n -= 1
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if not n:
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task._step()
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return False
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clock_event = Clock.schedule_interval(callback, 0)
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try:
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yield _sleep_forever
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finally:
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clock_event.cancel()
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