Custom LayoutManager

[StringKe]

I want to use LayoutManager to realize the effect in the video.

But I don't know which methods or events I should implement in LayoutManager?

https://share.cleanshot.com/rL7RMK3X

CleanShot.2023-12-28.at.17.22.48.mp4

[StringKe]

@ShaMan123 Should I inherit from LayoutManager and override the layoutObject method?

[StringKe]

There is a small problem, I have modified the live repo for your convenience.

Why isn't the position corrected after scheduling the triggerLayout?

I noticed some changes in the position, but not exactly correct.

[ShaMan123]

I think this issue is that once you change the position of the other object according to the active one the group center changes but that is not reflected anywhere so the layout manager uses the old center to reposition the entire group wrongly.
This is exactly the use of correction. Because the center of the group changes on the fly you need to figure out how to correct the position of the objects accordingly.
I am not sure...
https://stackblitz.com/edit/web-platform-b3u4ja?file=index.html

[StringKe]

Is there any way I can do an absolute position calculation?

Your modified live repo is calculated relative to group center point.

I tried to convert it to absolute position with relativePoint calculation and then again to relative position.

I'm not sure if this is possible, it doesn't work in my test scenario, maybe I'm using the wrong method.

[ShaMan123]

https://stackblitz.com/edit/web-platform-9j8cu7?file=index.html

[StringKe]

Thank you very much, for the first time I learned about the sendPointToPlane method.

[StringKe]

On another note, how do I make the LayoutManager act on the Canvas?

[StringKe]

Please describe it a bit more The layout manager was designed to be used by Group but I don't see why it can't be used with Canvas with some adjustments

I think Canvas should also support LayoutManager.

The implementation of nested elements should be left to its own parent (usually Group).

[StringKe]

Question is if it will be as useful

Very useful in specific scenarios like templates (reports, posters, product thumbnails).

Or maybe someone wants to write an html renderer using fabricjs (to handle layouts like flex grid).

[ShaMan123]

Cool, I think we should open a dedicated discussion and outline the pros etc. and what needs to change in the layout manager API (I can help)

[StringKe]

Agreed, you can create a new one where we discuss it.

[ShaMan123]

You should open it, it is your motivation and initiative