My tree is a whole
In addition to the model, the trees, the walls, the lights, the ground are all a single entity
I was going to put the project on the playground for you to look at, but when I ran it, nothing showed up
Well mesh merging is just one strategy. You need to try multiple alternative strategies. What will work is highly dependent on the specific scene and what you are trying to achieve.
If merged geometry is still too slow, trying splitting and instancing. At least this will be better for camera frustum culling.
Worst case scenario is you could split interiors off into separate scenes that are only loaded and displayed when needed. But I don’t think that’s necessary in this case.
First of all, the scene inside the casual elements are the existence of separate instance, trees, lighthouse, walls are as a whole, at the time of modeling, has been the case, the merger of the grid is useless, for the whole building is made of layers of single model, and use lod, modelers temporarily don’t have time to give me a separate modeling, I only have a set of models, not achieve the lod, I feel like I’m the only way is to render the model visible to the camera
Unfortunately without a repro we can’t help 