Multipass Generation
Simalar to VoxelGeneratorMultipassCB implemented in godot-voxel-tools, ITOC implemented a multipass chunk generation controller for cross-chunk structures like trees.
Such multi-layer (multi-pass) generation process is pretty flexible and versatile. However, it is not recommended for large structures (more than 60x60x60 blocks). Large structures can be generated together with vanilla world generator's sample points.