Rerun viewer becomes slow when there are several hundreds of entities

[emilk]

We currently don't have a good example of this. The best we got is

pixi run py-build-examples && pr -e examples open_photogrammetry_format --no-frames

and

• Add a new "Air Traffic Data" example #5449

Related issues

• Only recompute space-view heuristics if something has changed #3110
• Chunk ingestion performance regression because of compaction logic #8101
• Reference all performance bottlenecks highlighted by "air traffic" example #5799

[jleibs]

Here's a very simple example that makes the viewer totally unuable:

import rerun as rr

from rerun.datatypes import RotationAxisAngle

rr.init("rerun_example_many_entities", spawn=True)


def one_strip(number_points: int):
    return rr.LineStrips3D(
        [[0.3 if i % 2 == 0 else -0.3, i, 0] for i in range(number_points)],
    )


def rotate(theta: float):
    return rr.Transform3D(
        rotation_axis_angle=RotationAxisAngle(axis=[0, 0, 1], degrees=theta),
        axis_length=0,
    )


def draw_lines(lines_count: int, pts_per_line: int):
    theta_delta = 360 / lines_count
    for i in range(lines_count):
        rr.log(f"line_{i}", rotate(theta_delta * i))
        rr.log(f"line_{i}/strip", one_strip(pts_per_line))

draw_lines(5000, 10)