Root causes found for the 4K stalls and the second-footage memory
blowup (audit + code review):
- ticket bookkeeping leaked unbounded: the procpool ticket table and
the arena slot map only ever grew (50-100 tickets/sec during
playback, each pinning montage params and shm region views).
Completed/cancelled/superseded/crashed entries are now removed, and
the arena reaps fire-and-forget tickets once finished; the sync poll
path reaps via a terminal result() read. InFlight duplicate submits
now answer State immediately instead of sitting in the map forever.
- decode ran a full-resolution swscale to F32 RGBA (~132 MB at 4K)
plus a second full-res copy before downscaling to the 480px proxy:
RetrieveVideoParams.target_size lets swscale convert AND resize in
one pass (bilinear, matching the old Rust resampler), so a 4K
preview frame costs ~1 MB instead of ~260 MB of churn. This applies
to proxy AND full-res requests alike.
- per-process decoder cache was unbounded (each session pins an FFmpeg
context + 2 native decoded frames): LRU-capped at 16, eviction drops
the map entry (in-flight renders keep their Arc; Drop releases
FFmpeg).
- playback window completions were not generation-gated: a stale
render from before an edit landed in the rebuilt window (wrong frame
displayed, fresh request blocked). Stale completions now return
their shm slot credit instead.
- async audio prefetch used the polling ticket submit without ever
polling: switched to the fire-and-forget submit so entries reap.
Adding an effect to a clip did nothing: the sequence render is
flattened into a montage (decode + composite), and MontageClip carried
no effect data at all.
- MontageClip gains an ordered effect stack (type id / enabled /
effect input / parameter values); protocol v2 carries it as an
additive wire field (older peers default to an empty stack).
- renderops::video_montage fills the stack from the effect chain
(the footage source node — the chain end without an effect input —
is dropped; the montage decodes the footage itself). Export
(oak-task) and the multicam single-track montage fill it too.
- The worker applies the stack between decode and composite: built-in
Opacity gets a CPU evaluator (C++ opacity.frag parity — whole vec4,
alpha included, unity pass-through); everything else dispatches as an
OFX plugin job through a new instance-factory slot (oak-plugin
lazily creates + caches one instance per identifier per render
process) with the montage's parameters injected. Disabled effects
bypass (the C++ traverser pushes the effect input through). Unknown
types warn once per type id and pass through — no silent no-ops.
Not covered (explicitly): Transform/Crop and the other ~30 built-in
effects have no CPU evaluator in oak-render (they pass through with a
warning), keyframed parameter animation, audio effect chains, and the
CLI's simplified montage.
Acceptance: a real 50% Opacity on real media quarters the rendered
pixels both in-process (renderops test) and through a real worker
process over IPC + shared memory (procpool_integration test);
disabling restores the plain render byte-for-byte.
All crates take the oak-* kebab-case naming (oak-audio, oak-codec,
oak-common, oak-core, oak-ffmpeg-link, oak-node, oak-otio, oak-plugin,
oak-render, oak-storage, oak-task, oak-timeline, oak-undo), with the
lib identifiers rewritten (oakrender:: -> oak_render::, oakcore_rs:: ->
oak_core::, ...) across all 226 referencing files.
The GUI application moves from the workspace root into
crates/oak-app/: src/, build.rs (paths fixed for the new location) and
tests/ travel with it, the root Cargo.toml becomes workspace-only
([workspace] + workspace.package + profiles), and the app package
inherits the workspace version. The screenshots example becomes a
standalone crate examples/simple_player/ with its own Cargo.toml.
Every crate now inherits the single workspace version
(version.workspace = true), and the workflows' crate paths and the
build docs follow the renames.
Validated with a clean cargo check --workspace.
Mike-Solar