Performance issue

I made a simple test where I draw multiple identical vertical lines from bottom to top in cycle. I found out that each new line renders much slower than previous one. Is it a bug or did I do something wrong?

def c(coord):
  if isinstance(coord, (np.ndarray, list)) and len(coord) == 3:
    return np.asarray(coord, dtype=np.float32) / 135
  else:
    return coord / 1.35

import numpy as np
from datetime import datetime

class mainScene(Scene):
  CONFIG = {
      "camera_config": {"background_color": '#ffffff'},
  }
  def construct(self):
    for j in np.arange(-958.5, 960, 2):
      start = datetime.now()
      for _ in np.arange(-540, 540, 2):
        line = Line(c([j, _, 0]), c([j, _+1, 0]), stroke_width=c(1), stroke_color='#000000')
        self.add(line)
        if _ == 538: print(int(j + 959.5), datetime.now() - start)
    
    self.wait(.1)

1 0:00:00.389817
3 0:00:00.927884
5 0:00:01.458466
7 0:00:01.970841
9 0:00:02.500315
11 0:00:03.015520
13 0:00:03.712525
15 0:00:04.210232
17 0:00:04.822479
19 0:00:05.358658
21 0:00:06.160043

[zavden]

self.remove(mob1,mob2,...)

[zavden]

That is quite obvious if you think about how Manim should be working internally. Manim draws each object in each frame according to the preset order in the variable self.mobjects, as you already know self.add (mob) adds mob to self.mobjects. That means that the more mobjects added to the animation, more mobjects each frame will have to draw, for memory consumption. If you add 1000 mobjects with self.add then in each frame the 1000 mobjects will have to be added according to the order of self.mobjects. There is no way around this because Manim was designed this way.

This behavior is not similar to self.play, because the animated object is not successively added to memory. For example:

self.add(circle)
self.play(circle.shift,LEFT)

In this animation there is only one circle object, and in the course of the animation no other mobject is added or removed, all objects in self.mobjects remain intact, self.mobjects is the same before and after the animation. There are some animations that can delete (FadeOut, etc.) or add (FadeIn, Write, GrowFromCenter, etc.) an object at the end, but they do not do it in large quantities as you intend to do so.

Manim was not designed for such complex animations, Grant himself on his official website has said this, if Manim is not trained to do this I recommend using some other animation tool, such as Blender (in which you can also use Python 3).