Struct ScratchRegion 

pub struct ScratchRegion { /* private fields */ }

Bump-allocated scratch space for temporary per-propagator data.

Propagators can request temporary f32 slices from scratch space for intermediate calculations (e.g. neighbourhood sums, gradient buffers). The scratch region is reset between propagator executions within a single tick — allocations do not persist across propagators or ticks.

Example (conceptual)

let slice = scratch.alloc(100)?;
// use slice for intermediate computation
// scratch.reset() called by engine before next propagator

Implementations

impl ScratchRegion

pub fn new(initial_capacity: usize) -> Self

Create a new scratch region with the given initial capacity (in f32 elements).

pub fn alloc(&mut self, len: usize) -> Option<&mut [f32]>

Allocate len f32 elements from scratch space.

Returns a zero-initialised mutable slice. Returns None if the scratch region cannot grow to accommodate the request (this should not happen in practice since Vec grows on demand; None is returned only if the system is out of memory).

pub fn reset(&mut self)

Reset the scratch region for the next propagator.

This does NOT deallocate or zero the backing storage — it simply resets the bump pointer. The next alloc call will overwrite stale data with zeroes before returning.

pub fn used(&self) -> usize

Number of f32 elements currently allocated.

pub fn capacity(&self) -> usize

Total capacity of the backing storage in f32 elements.

pub fn memory_bytes(&self) -> usize

Memory usage of the backing storage in bytes.