Struct FuzzedBiomeColumn 

struct FuzzedBiomeColumn<'a> {

    biome_data: &'a [u16],
    section_count: usize,
    biome_zoom_seed: i64,
    parent_x: i32,
    parent_z: i32,
    fract_x: f64,
    fract_z: f64,
    min_y: i32,
    chunk_quart_x: i32,
    chunk_quart_z: i32,
    neighbor_biomes: &'a dyn Fn(IVec3) -> u16,
    cached_parent_y: i32,
    candidates: [(f64, f64); 8],
    rval_after_cx: [i64; 2],
}

Column-local cache for fuzzed biome lookups (vanilla BiomeManager.getBiome()).

Within a column, parent_x, parent_z, fract_x, fract_z are constant. The 8 Voronoi candidate fiddle values (computed via 8 serial LCG calls each) only change when parent_y changes (every 4 blocks). This cache precomputes the fiddle values and X/Z distance components per parent_y group, reducing per-block work to 8 additions + 8 multiplies + 8 comparisons.

Fields

biome_data: &'a [u16]

section_count: usize

biome_zoom_seed: i64

parent_x: i32

parent_z: i32

fract_x: f64

fract_z: f64

min_y: i32

chunk_quart_x: i32

chunk_quart_z: i32

neighbor_biomes: &'a dyn Fn(IVec3) -> u16

cached_parent_y: i32

candidates: [(f64, f64); 8]

Per-candidate cached values: (fy, xz_partial_distance).

rval_after_cx: [i64; 2]

Precomputed lcg_next(seed, parent_x) and lcg_next(seed, parent_x + 1).

Implementations

impl<'a> FuzzedBiomeColumn<'a>

fn new( biome_data: &'a [u16], section_count: usize, biome_zoom_seed: i64, block_x: i32, block_z: i32, min_y: i32, chunk_quart_x: i32, chunk_quart_z: i32, neighbor_biomes: &'a dyn Fn(IVec3) -> u16, ) -> Self

fn compute_cy_group(&mut self, cy: i32, high: bool)

Compute candidates for a given cy, writing to either the low (bit1=0) or high (bit1=1) slots. Shares the lcg_next(seed, cx) precomputation and the lcg_next(_, cy) step within each cx group.

fn recompute_candidates(&mut self, parent_y: i32)

Recompute the 8 candidate fiddle values and X/Z distance for a new parent_y.

When scanning downward (parent_y decreases by 1), the old low-cy candidates (cy=old_parent_y) match the new high-cy slots (cy=new_parent_y+1), so only the 4 new low-cy candidates need fresh LCG computation.

fn get(&mut self, block_y: i32) -> u16

Fuzzed biome lookup for a given block_y.

Trait Implementations

impl SurfaceBiomeProvider for FuzzedBiomeColumn<'_>

fn biome_id(&mut self, block_y: i32) -> u16

Returns the biome ID for the given block Y in the current X/Z column.