Struct BufferPool 

pub struct BufferPool {
    buffer: Buffer,
    label: &'static str,
    usage: BufferUsages,
    allocator: Allocator,
}

One GPU buffer sub-allocated into many ranges.

See the module documentation for what a pool is for.

Fields

buffer: Buffer

The buffer every range lives in.

label: &'static str

The label the buffer is created with, reused when it is replaced.

usage: BufferUsages

The usages the buffer is created with.

allocator: Allocator

Where the free space is.

Implementations

impl BufferPool

pub fn new( device: &Device, label: &'static str, usage: BufferUsages, size: u64, ) -> Self

Creates a pool over a buffer of size bytes with the given usages.

The buffer is created immediately. size is rounded up to a multiple of COPY_BUFFER_ALIGNMENT.

Panics

Panics if the usages do not include [wgpu::BufferUsages::COPY_DST], which the pool needs to grow.

pub fn buffer(&self) -> &Buffer

The buffer every range lives in.

This changes when the pool grows, so read it again instead of holding one: a range stays valid across a grow, but names no buffer of its own to read it from.

pub fn size(&self) -> u64

The pool’s total size, in bytes.

pub fn free_space(&self) -> u32

The free space left, in bytes.

pub fn allocation_size(&self, allocation: Allocation) -> u32

The size reserved for allocation, in bytes.

This is the requested size rounded up to the alignment.

pub fn allocate( &mut self, device: &Device, queue: &Queue, size: u32, ) -> Option<BufferRange>

Reserves a range of size bytes, growing the pool if it does not fit.

Returns None only if the pool cannot grow any further (its size would overflow a u32, or it has run out of node slots for its ranges). The returned range’s offset is a multiple of COPY_BUFFER_ALIGNMENT, and its allocation covers size rounded up to it.

Growing allocates a new buffer 1.5x the pool’s size, copies the old contents into it, and appends the difference to the allocator. Existing ranges keep their offsets, but the buffer they name changes, so a caller holding one must re-read BufferPool::buffer.

pub fn release(&mut self, allocation: Allocation)

Hands a range back to the pool.

Panics

Panics if the allocation was already released.

fn range(&self, allocation: Allocation) -> BufferRange

Builds the handle for a fresh allocation.

fn grow(&mut self, device: &Device, queue: &Queue, size: u32) -> Option<()>

Grows the pool by 1.5x until size fits, copying the contents across.

Returns None if the pool cannot grow, leaving it unchanged.

Trait Implementations

impl Debug for BufferPool

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.