Hi guys 
I am working on a new library for rendering octahedral impostors and I’ve created a small demo with a terrain 3072 x 3072 and 200k trees. It should work quite good on mobile as well.
The terrain is managed with BatchedMesh with an extension to have LODs, generated with meshoptimizer.
For the trees, I used InstancedMesh2, with a BVH for frustum culling, adding two more LODs, one created with meshoptimizer (distance from 15 to 100) and the other using an octahedral impostor (distance 100+).
Demo: https://octahedral-impostor.vercel.app
Github : https://github.com/agargaro/octahedral-impostor
As soon as I find some time, I would like to share with you the details that allowed me to optimize it on mobile devices too.
