Struct Cache

struct Cache<T> {
    map: HashMap<i64, (u64, usize, Arc<T>)>,
    bytes: usize,
    tick: u64,
    protect: (i64, i64),
}

Byte-budgeted LRU keyed by frame index on the project fps grid. The whole cache is cleared on any change that could affect the picture, so entries never go stale.

Fields

map: HashMap<i64, (u64, usize, Arc<T>)>

frame index -> (last-use tick, payload bytes, payload)

bytes: usize

tick: u64

protect: (i64, i64)

Inclusive index range evicted last (playhead trail + prefetch horizon).

Implementations

impl<T> Cache<T>

fn new() -> Self

fn set_protect(&mut self, lo: i64, hi: i64)

Frames in [lo, hi] are evicted only when nothing else is left to evict.

fn get(&mut self, idx: i64) -> Option<Arc<T>>

fn contains(&self, idx: i64) -> bool

fn insert(&mut self, idx: i64, bytes: usize, v: Arc<T>) -> Vec<Arc<T>>

Insert and evict LRU entries down to the budget; evicted payloads come back for buffer recycling.

fn evict_range(&mut self, lo: i64, hi: i64) -> Vec<Arc<T>>

Drop every entry whose index lies in [lo, hi], handing payloads back for recycling.

fn drain(&mut self) -> Vec<Arc<T>>

Empty the cache, handing every payload back for buffer recycling.