Difficult-Rocket/libs/pyglet/image/animation.py
2023-03-22 00:08:03 +08:00

180 lines
6.3 KiB
Python

"""2D Animations
Animations can be used by the :py:class:`~pyglet.sprite.Sprite` class in place
of static images. They are essentially containers for individual image frames,
with a duration per frame. They can be infinitely looping, or stop at the last
frame. You can load Animations from disk, such as from GIF files::
ani = pyglet.resource.animation('walking.gif')
sprite = pyglet.sprite.Sprite(img=ani)
Alternatively, you can create your own Animations from a sequence of images
by using the :py:meth:`~Animation.from_image_sequence` method::
images = [pyglet.resource.image('walk_a.png'),
pyglet.resource.image('walk_b.png'),
pyglet.resource.image('walk_c.png')]
ani = pyglet.image.Animation.from_image_sequence(images, duration=0.1, loop=True)
You can also use an :py:class:`pyglet.image.ImageGrid`, which is iterable::
sprite_sheet = pyglet.resource.image('my_sprite_sheet.png')
image_grid = pyglet.image.ImageGrid(sprite_sheet, rows=1, columns=5)
ani = pyglet.image.Animation.from_image_sequence(image_grid, duration=0.1)
In the above examples, all of the Animation Frames have the same duration.
If you wish to adjust this, you can manually create the Animation from a list of
:py:class:`~AnimationFrame`::
image_a = pyglet.resource.image('walk_a.png')
image_b = pyglet.resource.image('walk_b.png')
image_c = pyglet.resource.image('walk_c.png')
frame_a = pyglet.image.AnimationFrame(image_a, duration=0.1)
frame_b = pyglet.image.AnimationFrame(image_b, duration=0.2)
frame_c = pyglet.image.AnimationFrame(image_c, duration=0.1)
ani = pyglet.image.Animation(frames=[frame_a, frame_b, frame_c])
"""
class Animation:
"""Sequence of images with timing information.
If no frames of the animation have a duration of ``None``, the animation
loops continuously; otherwise the animation stops at the first frame with
duration of ``None``.
:Ivariables:
`frames` : list of `~pyglet.image.AnimationFrame`
The frames that make up the animation.
"""
def __init__(self, frames):
"""Create an animation directly from a list of frames.
:Parameters:
`frames` : list of `~pyglet.image.AnimationFrame`
The frames that make up the animation.
"""
assert len(frames)
self.frames = frames
def add_to_texture_bin(self, texture_bin, border=0):
"""Add the images of the animation to a :py:class:`~pyglet.image.atlas.TextureBin`.
The animation frames are modified in-place to refer to the texture bin
regions.
:Parameters:
`texture_bin` : `~pyglet.image.atlas.TextureBin`
Texture bin to upload animation frames into.
`border` : int
Leaves specified pixels of blank space around
each image frame when adding to the TextureBin.
"""
for frame in self.frames:
frame.image = texture_bin.add(frame.image, border)
def get_transform(self, flip_x=False, flip_y=False, rotate=0):
"""Create a copy of this animation applying a simple transformation.
The transformation is applied around the image's anchor point of
each frame. The texture data is shared between the original animation
and the transformed animation.
:Parameters:
`flip_x` : bool
If True, the returned animation will be flipped horizontally.
`flip_y` : bool
If True, the returned animation will be flipped vertically.
`rotate` : int
Degrees of clockwise rotation of the returned animation. Only
90-degree increments are supported.
:rtype: :py:class:`~pyglet.image.Animation`
"""
frames = [AnimationFrame(frame.image.get_texture().get_transform(flip_x, flip_y, rotate),
frame.duration) for frame in self.frames]
return Animation(frames)
def get_duration(self):
"""Get the total duration of the animation in seconds.
:rtype: float
"""
return sum([frame.duration for frame in self.frames if frame.duration is not None])
def get_max_width(self):
"""Get the maximum image frame width.
This method is useful for determining texture space requirements: due
to the use of ``anchor_x`` the actual required playback area may be
larger.
:rtype: int
"""
return max([frame.image.width for frame in self.frames])
def get_max_height(self):
"""Get the maximum image frame height.
This method is useful for determining texture space requirements: due
to the use of ``anchor_y`` the actual required playback area may be
larger.
:rtype: int
"""
return max([frame.image.height for frame in self.frames])
@classmethod
def from_image_sequence(cls, sequence, duration, loop=True):
"""Create an animation from a list of images and a constant framerate.
:Parameters:
`sequence` : list of `~pyglet.image.AbstractImage`
Images that make up the animation, in sequence.
`duration` : float
Number of seconds to display each image.
`loop` : bool
If True, the animation will loop continuously.
:rtype: :py:class:`~pyglet.image.Animation`
"""
frames = [AnimationFrame(image, duration) for image in sequence]
if not loop:
frames[-1].duration = None
return cls(frames)
def __repr__(self):
return "Animation(frames={0})".format(len(self.frames))
class AnimationFrame:
"""A single frame of an animation."""
__slots__ = 'image', 'duration'
def __init__(self, image, duration):
"""Create an animation frame from an image.
:Parameters:
`image` : `~pyglet.image.AbstractImage`
The image of this frame.
`duration` : float
Number of seconds to display the frame, or ``None`` if it is
the last frame in the animation.
"""
self.image = image
self.duration = duration
def __repr__(self):
return "AnimationFrame({0}, duration={1})".format(self.image, self.duration)