Batch operations with 3D scene.

[kovalp]

Currently, the 3D scene is updated whenever any primitive is changed (moved, rotated, colored). This is very convenient and intuitive. However, the immediate updates cause a relatively slow data transfer Python-JavaScript. For example, once a 3D scene of a few thousands of boxes is initialized it becomes interactive (mouse) with no visible lags. However, the initialization is visibly slow. During the initialization the user might see a box appearing at the origin and then moved to its destination place with the right color/opacity.

It would be nice to introduce a batch update of the scene, when the programmer could construct the primitives without any Python-JavaScript communication. Once all the primitives constructed/updated, the communication with the browser should be done in a single message and explicitly.

An idea could be to buffer the information about changes while calling the methods on primitives, e.g. box.move(...) or box.material(...). Once the scene is defined, a method scene.apply() would communicate the changes in a one shot.

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Related issue: #2989

[falkoschindler]

Thanks for this feature request, @kovalp!

I managed to reproduce the behavior you're describing with the following code:

with ui.scene() as scene:
    scene.move_camera(y=-6, z=7)
    for x in range(100):
        for y in range(100):
            scene.box().scale(0.09).move(x / 10 - 5, y / 10 - 5)

A solution might be to send multiple messages at once in https://github.com/zauberzeug/nicegui/blob/main/nicegui/outbox.py like we do for updates.

[kovalp]

Is it already possible? For 3D scene?

[falkoschindler]

No, that's a change we must implement in outbox.py.

[falkoschindler]

I created PR #3017 to play around with sending multiple messages at once.