Struct TilePrefetcher 

pub struct TilePrefetcher {
    pub radius: u8,
    pub max_zoom_delta: u8,
}

Pre-fetches neighboring tiles based on the current access pattern.

Fields

radius: u8

How many tiles around the current tile to prefetch (Chebyshev radius).

max_zoom_delta: u8

Prefetch this many zoom levels above and below the current zoom.

Implementations

impl TilePrefetcher

pub fn new(radius: u8) -> Self

Creates a new TilePrefetcher with the given radius and a default max_zoom_delta of 1.

pub fn neighbors(&self, key: &TileKey) -> Vec<TileKey>

Returns the set of tiles to prefetch for a given key.

Includes the ring of neighbors at the same zoom level plus rings at zoom ± 1 .. max_zoom_delta. The tile itself is excluded.

pub fn ring_at_zoom(&self, key: &TileKey, zoom: u8, radius: u8) -> Vec<TileKey>

Returns all tiles in a square ring of radius around key at zoom.

Coordinates are clamped to zero via saturating arithmetic so that boundary tiles are valid (x, y ≥ 0).