3b1b-manim/manimlib/scene/zoomed_scene.py
2020-02-13 10:50:56 -08:00

90 lines
3.4 KiB
Python

from manimlib.animation.transform import ApplyMethod
from manimlib.camera.moving_camera import MovingCamera
from manimlib.camera.multi_camera import MultiCamera
from manimlib.constants import *
from manimlib.scene.moving_camera_scene import MovingCameraScene
from manimlib.utils.simple_functions import fdiv
# Note, any scenes from old videos using ZoomedScene will almost certainly
# break, as it was restructured.
# TODO, this scene no longer works
class ZoomedScene(MovingCameraScene):
CONFIG = {
"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,
}
def setup(self):
MovingCameraScene.setup(self)
# 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
def activate_zooming(self, animate=False):
self.zoom_activated = True
self.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,
)
def get_zoom_in_animation(self, run_time=2, **kwargs):
frame = self.zoomed_camera.frame
full_frame_height = self.camera.get_frame_height()
full_frame_width = self.camera.get_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)
def get_zoomed_display_pop_out_animation(self, **kwargs):
display = self.zoomed_display
display.save_state(use_deepcopy=True)
display.replace(self.zoomed_camera.frame, stretch=True)
return ApplyMethod(display.restore)
def get_zoom_factor(self):
return fdiv(
self.zoomed_camera.frame.get_height(),
self.zoomed_display.get_height()
)