Source code for manim.scene.zoomed_scene

"""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=False): """ This method is used to activate the zooming for the zoomed_camera. Parameters ---------- animate : bool, optional 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=2, **kwargs): """ Returns the animation of camera zooming in. Parameters ---------- run_time : int or float, optional 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