"""A scene supporting zooming in on a specified section.
Examples
--------
.. manim:: UseZoomedScene
class UseZoomedScene(ZoomedScene):
def construct(self):
dot = Dot().set_color(GREEN)
self.add(dot)
self.wait(1)
self.activate_zooming(animate=False)
self.wait(1)
self.play(dot.animate.shift(LEFT))
.. manim:: ChangingZoomScale
class ChangingZoomScale(ZoomedScene):
def __init__(self, **kwargs):
ZoomedScene.__init__(
self,
zoom_factor=0.3,
zoomed_display_height=1,
zoomed_display_width=3,
image_frame_stroke_width=20,
zoomed_camera_config={
"default_frame_stroke_width": 3,
},
**kwargs
)
def construct(self):
dot = Dot().set_color(GREEN)
sq = Circle(fill_opacity=1, radius=0.2).next_to(dot, RIGHT)
self.add(dot, sq)
self.wait(1)
self.activate_zooming(animate=False)
self.wait(1)
self.play(dot.animate.shift(LEFT * 0.3))
self.play(self.zoomed_camera.frame.animate.scale(4))
self.play(self.zoomed_camera.frame.animate.shift(0.5 * DOWN))
"""
from __future__ import annotations
__all__ = ["ZoomedScene"]
from ..animation.transform import ApplyMethod
from ..camera.moving_camera import MovingCamera
from ..camera.multi_camera import MultiCamera
from ..constants import *
from ..mobject.types.image_mobject import ImageMobjectFromCamera
from ..scene.moving_camera_scene import MovingCameraScene
# Note, any scenes from old videos using ZoomedScene will almost certainly
# break, as it was restructured.
[docs]class ZoomedScene(MovingCameraScene):
"""
This is a Scene with special configurations made for when
a particular part of the scene must be zoomed in on and displayed
separately.
"""
def __init__(
self,
camera_class=MultiCamera,
zoomed_display_height=3,
zoomed_display_width=3,
zoomed_display_center=None,
zoomed_display_corner=UP + RIGHT,
zoomed_display_corner_buff=DEFAULT_MOBJECT_TO_EDGE_BUFFER,
zoomed_camera_config={
"default_frame_stroke_width": 2,
"background_opacity": 1,
},
zoomed_camera_image_mobject_config={},
zoomed_camera_frame_starting_position=ORIGIN,
zoom_factor=0.15,
image_frame_stroke_width=3,
zoom_activated=False,
**kwargs,
):
self.zoomed_display_height = zoomed_display_height
self.zoomed_display_width = zoomed_display_width
self.zoomed_display_center = zoomed_display_center
self.zoomed_display_corner = zoomed_display_corner
self.zoomed_display_corner_buff = zoomed_display_corner_buff
self.zoomed_camera_config = zoomed_camera_config
self.zoomed_camera_image_mobject_config = zoomed_camera_image_mobject_config
self.zoomed_camera_frame_starting_position = (
zoomed_camera_frame_starting_position
)
self.zoom_factor = zoom_factor
self.image_frame_stroke_width = image_frame_stroke_width
self.zoom_activated = zoom_activated
super().__init__(camera_class=camera_class, **kwargs)
[docs] def setup(self):
"""
This method is used internally by Manim to
setup the scene for proper use.
"""
super().setup()
# Initialize camera and display
zoomed_camera = MovingCamera(**self.zoomed_camera_config)
zoomed_display = ImageMobjectFromCamera(
zoomed_camera, **self.zoomed_camera_image_mobject_config
)
zoomed_display.add_display_frame()
for mob in zoomed_camera.frame, zoomed_display:
mob.stretch_to_fit_height(self.zoomed_display_height)
mob.stretch_to_fit_width(self.zoomed_display_width)
zoomed_camera.frame.scale(self.zoom_factor)
# Position camera and display
zoomed_camera.frame.move_to(self.zoomed_camera_frame_starting_position)
if self.zoomed_display_center is not None:
zoomed_display.move_to(self.zoomed_display_center)
else:
zoomed_display.to_corner(
self.zoomed_display_corner,
buff=self.zoomed_display_corner_buff,
)
self.zoomed_camera = zoomed_camera
self.zoomed_display = zoomed_display
[docs] def activate_zooming(self, animate: bool = False):
"""
This method is used to activate the zooming for
the zoomed_camera.
Parameters
----------
animate
Whether or not to animate the activation
of the zoomed camera.
"""
self.zoom_activated = True
self.renderer.camera.add_image_mobject_from_camera(self.zoomed_display)
if animate:
self.play(self.get_zoom_in_animation())
self.play(self.get_zoomed_display_pop_out_animation())
self.add_foreground_mobjects(
self.zoomed_camera.frame,
self.zoomed_display,
)
[docs] def get_zoom_in_animation(self, run_time: float = 2, **kwargs):
"""
Returns the animation of camera zooming in.
Parameters
----------
run_time
The run_time of the animation of the camera zooming in.
**kwargs
Any valid keyword arguments of ApplyMethod()
Returns
-------
ApplyMethod
The animation of the camera zooming in.
"""
frame = self.zoomed_camera.frame
full_frame_height = self.camera.frame_height
full_frame_width = self.camera.frame_width
frame.save_state()
frame.stretch_to_fit_width(full_frame_width)
frame.stretch_to_fit_height(full_frame_height)
frame.center()
frame.set_stroke(width=0)
return ApplyMethod(frame.restore, run_time=run_time, **kwargs)
[docs] def get_zoomed_display_pop_out_animation(self, **kwargs):
"""
This is the animation of the popping out of the
mini-display that shows the content of the zoomed
camera.
Returns
-------
ApplyMethod
The Animation of the Zoomed Display popping out.
"""
display = self.zoomed_display
display.save_state()
display.replace(self.zoomed_camera.frame, stretch=True)
return ApplyMethod(display.restore)
[docs] def get_zoom_factor(self):
"""
Returns the Zoom factor of the Zoomed camera.
Defined as the ratio between the height of the
zoomed camera and the height of the zoomed mini
display.
Returns
-------
float
The zoom factor.
"""
return self.zoomed_camera.frame.height / self.zoomed_display.height