Struct SpreadContext 

pub(super) struct SpreadContext<'a> {
    state_cache: FxHashMap<i16, BlockStateId>,
    hole_cache: FxHashMap<i16, bool>,
    world: &'a Arc<World>,
    origin: BlockPos,
}

Context for fluid spread calculations with local caching.

This is created fresh for each get_spread() call and caches:

• BlockState lookups by relative position
• Hole check results by relative position

Fields

state_cache: FxHashMap<i16, BlockStateId>

Cache for block states by encoded relative position

hole_cache: FxHashMap<i16, bool>

Cache for hole check results by encoded relative position

world: &'a Arc<World>

Reference to world for cache misses

origin: BlockPos

The block from which spreading originates — used to compute relative cache keys.

Implementations

impl<'a> SpreadContext<'a>

pub(super) fn new(world: &'a Arc<World>, origin: BlockPos) -> Self

Creates a new SpreadContext anchored at origin.

origin must be the block that triggered the spread (the block passed to get_spread()), matching vanilla’s new FlowingFluid.SpreadContext(level, blockPos).

fn encode_key(&self, pos: BlockPos) -> i16

Encodes a world position into a short cache key relative to the spread origin.

pub fn get_block_state(&mut self, pos: BlockPos) -> BlockStateId

Gets the cached block state at the given position, querying the world if not cached.

pub fn cache_block_state(&mut self, pos: BlockPos, state: BlockStateId)

Seeds a state already read by the outer spread calculation.

pub fn is_hole(&mut self, pos: BlockPos, fluid_id: FluidRef) -> bool

Checks if the position is a hole (can fluid flow down into it?), with caching.

pub(super) const fn world(&self) -> &'a Arc<World>

Returns a reference to the world.