Editor: script to update geometry width/height segments

Questions
1

I am using the editor to create a plane with the displacement map applied to; i set 200 segments in the width and height.

I would like to add an script to create a level of detail, when LOD near is these 200 segments and when far distance from the camera the segments reduces to 1.

How is done this script in three.js?

2

You have two examples here to start.
But going further than these require exponential amount of work.
I hope you’re motivated

Simple camera-based LOD for procedural mesh
https://threejs.org/examples/?q=lod#webgl_lod

Complex mesh batching
https://threejs.org/examples/?q=lod#webgl_batch_lod_bvh

3

Do you want to increase LOD for the plane? Or for objects?
I use textures a lot to increase apparent resolution.
There is also a technique where you can use different LODs for a single plane, by subdividing nearby grids. You can find a good discussion of this here on the SimonDev website..