Shofel2_T124_python/venv/lib/python3.10/site-packages/asciimatics/scene.py

137 lines
4.5 KiB
Python

"""
This module defines Scene objects for animation purposes. For more details, see
http://asciimatics.readthedocs.io/en/latest/animation.html
"""
from __future__ import division
from __future__ import absolute_import
from __future__ import print_function
from __future__ import unicode_literals
from builtins import object
class Scene(object):
"""
Class to store the details of a single scene to be displayed. This is
made up of a set of :py:obj:`.Effect` objects. See the documentation for
Effect to understand the interaction between the two classes and
http://asciimatics.readthedocs.io/en/latest/animation.html for how to use them together.
"""
def __init__(self, effects, duration=0, clear=True, name=None):
"""
:param effects: The list of effects to apply to this scene.
:param duration: The number of frames in this Scene. A value of 0 means that the Scene
should query the Effects to find the duration. A value of -1 means don't stop.
:param clear: Whether to clear the Screen at the start of the Scene.
:param name: Optional name to identify the scene.
"""
self._effects = []
for effect in effects:
self.add_effect(effect, reset=False)
self._duration = duration
if duration == 0:
self._duration = max([x.stop_frame for x in effects])
self._clear = clear
self._name = name
def reset(self, old_scene=None, screen=None):
"""
Reset the scene ready for playing.
:param old_scene: The previous version of this Scene that was running before the
application reset - e.g. due to a screen resize.
:param screen: New screen to use if old_scene is not None.
"""
# Always reset all the effects.
for effect in self._effects:
effect.reset()
# If we have an old Scene to recreate, get the data out of that and
# apply it where possible by cloning objects where appropriate.
if old_scene:
for old_effect in old_scene.effects:
# catching AttributeErrors here has hidden bugs, so explicitly
# check for the cloning interface before calling it.
if hasattr(old_effect, "clone"):
old_effect.clone(screen, self)
def exit(self):
"""
Handle any tidy up required on the exit of the Scene.
"""
# Save off any persistent state for each effect.
for effect in self._effects:
if hasattr(effect, "save"):
effect.save()
def add_effect(self, effect, reset=True):
"""
Add an effect to the Scene.
This method can be called at any time - even when playing the Scene. The default logic
assumes that the Effect needs to be reset before being displayed. This can be overridden
using the `reset` parameter.
:param effect: The Effect to be added.
:param reset: Whether to reset the Effect that has just been added.
"""
# Reset the effect in case this is in the middle of a Scene.
if reset:
effect.reset()
effect.register_scene(self)
self._effects.append(effect)
def remove_effect(self, effect):
"""
Remove an effect from the scene.
:param effect: The effect to remove.
"""
self._effects.remove(effect)
def process_event(self, event):
"""
Process a new input event.
This method will pass the event on to any Effects in reverse Z order so that the
top-most Effect has priority.
:param event: The Event that has been triggered.
:returns: None if the Scene processed the event, else the original event.
"""
for effect in reversed(self._effects):
event = effect.process_event(event)
if event is None:
break
return event
@property
def name(self):
"""
:return: The name of this Scene. May be None.
"""
return self._name
@property
def effects(self):
"""
:return: The list of Effects in this Scene.
"""
return self._effects
@property
def duration(self):
"""
:return: The length of the scene in frames.
"""
return self._duration
@property
def clear(self):
"""
:return: Whether the Scene should clear at the start.
"""
return self._clear