refactor/simplify_empty_chunks_usage

[piellardj]

refactor: allow simplied input object for empty chunks

The VoxelmapViewer.enqueuePatch method now takes as input as VoxelsChunkData which is:

type VoxelsChunkDataEmpty = {
    readonly size: THREE.Vector3;
    readonly isEmpty: true;
};
type VoxelsChunkDataNotEmpty = {
    readonly size: THREE.Vector3;
    readonly data: Uint16Array;
    readonly dataOrdering: VoxelsChunkOrdering;
    readonly isEmpty: false;
};
type VoxelsChunkData = VoxelsChunkDataEmpty | VoxelsChunkDataNotEmpty;

which means if a chunk is empty, there is no need to send a big Uint16Array full of zeroes.

Also improve performance when processing those empty chunks.

[Sceat]

/merge

[github-actions]

Success! Fast forwarded master to refactor/simplify_empty_chunks_usage! git checkout master && git merge refactor/simplify_empty_chunks_usage --ff-only