styx-core

Core primitives shared across the stack: buffer pools, frame leases/layouts, bounded queues, FourCc/format types, controls, and lightweight metrics.

Documentation

• https://docs.rs/styx-core-rs

Install

[dependencies]
styx-core-rs = "0.1.0"

Modules

• buffer: BufferPool, BufferLease, FrameLease, plane views, and helpers like plane_layout_from_dims/plane_layout_with_stride.
• queue: bounded/newest/unbounded queues with backpressure-aware SendOutcome/RecvOutcome.
• format: FourCc, Resolution, MediaFormat, Interval/IntervalStepwise, and ColorSpace.
• controls: ControlId, ControlMeta, ControlValue, and validation logic.
• metrics: simple hit/miss/allocation counters for pools.

Zero-copy buffers and frames

Frames are built from pooled buffers to avoid churn:

use styx_core::prelude::*;

let pool = BufferPool::with_limits(4, 1 << 20, 8);
let res = Resolution::new(640, 480).unwrap();
let layout = plane_layout_from_dims(res.width, res.height, 3);
let meta = FrameMeta::new(MediaFormat::new(FourCc::new(*b"RG24"), res, ColorSpace::Srgb), 0);
let frame = FrameLease::single_plane(meta, pool.lease(), layout.len, layout.stride);

FrameLease exposes immutable/mutable plane views and returns buffers to the pool on drop. Use planes_mut for in-place writes; multi-plane layouts are supported via FrameLease::multi_plane.

Bounded queues

queue::bounded provides a non-blocking bounded channel:

use styx_core::prelude::*;

let (tx, rx) = bounded::<FrameLease>(4);
match tx.send(frame) {
    SendOutcome::Sent => {},
    SendOutcome::Closed => {},
    SendOutcome::Full(f) => { /* backpressure */ }
}

match rx.recv() {
    RecvOutcome::Data(frame) => { /* consume */ }
    RecvOutcome::Empty => { /* try again */ }
    RecvOutcome::Closed => {}
}

Formats and controls

MediaFormat bundles FourCc, resolution, and color space; Interval describes frame pacing; ControlMeta + ControlValue carry backend controls with validation helpers.