Implement Chunk Loading Levels, Chunk Tickets, and Staged Chunk Generation #1062
Description
I've searched existing issues and couldn't find a duplicate.
- I confirm this is not a duplicate.
Is your feature request related to a problem? Please describe.
Cross chunk access is hard to deal with.
Describe the solution you'd like
Introduce chunk loading levels.
Add chunk tickets (e.g. player, portal, forced) to maintain chunk loading based on purpose and priority.
Implement staged chunk generation (e.g. from EMPTY to FULL) to allow asynchronous and incremental world generation.