Crate alpha2_render 

GPU compositing public API.

wgpu interop

By default the API names no wgpu type: sources enter as SourceViews and results leave as RenderedTextures and readbacks. Items taking or returning wgpu handles are documented only with the wgpu-interop feature, track wgpu’s major version, and are otherwise hidden and not part of this crate’s API.

Re-exports

pub use composite::LayerTransform;

pub use readback::PlaneTarget;

pub use readback::Rgba8Readback;

pub use readback::StagingPlane;

pub use readback::Yuv420pPlanes;

pub use readback::Yuv420pReadback;

pub use readback::Yuv420pTargets;

pub use readback::yuv420p_staging_bytes;

pub use yuv::ExternalTextureLease;

pub use yuv::PendingSourceWork;

pub use yuv::PreparedSourceTexture;

pub use yuv::SourceAlpha;

pub use yuv::SourcePlane;

pub use yuv::SourcePresentation;

pub use yuv::Yuv420Frame;

pub use yuv::YuvFrame;

Modules

hdr

HDR sources brought into the SDR working space.

Structs

AdapterDiagnostics

Adapter metadata recorded beside reproducible benchmark samples.

BenchmarkMetadata

Reproducible metadata envelope written beside benchmark measurements.

Color

A premultiplied sRGB storage value in 0..=1 with no color component above alpha; what an intermediate texture holds, not linear light.

CompiledEffect

A compiled runtime effect, ready for Renderer::register_compiled on the same renderer.

CpuImage

A CPU picture of premultiplied sRGB RGBA, like every GPU intermediate.

CpuRenderStats

Counts of what the CPU renderer has drawn, for metrics.

CpuRenderer

A renderer that draws RenderGraphs on the CPU with no GPU or driver.

CpuSource

A CPU graph source (crate::SourceView::cpu) holding premultiplied sRGB RGBA, like every GPU source texture. Decoded frames convert on first draw and the result is kept.

DegradationDecision

Effective controls and every observable fallback decision.

EffectDef

Data-only runtime effect, transition, or generator definition.

EffectId

Stable identity of one registered effect version.

EffectInputs

Named images an effect node samples besides its source, sorted by name, one node per name.

EffectParams

Named values for one runtime effect invocation, sorted by name, one value per name.

EffectResources

Named resource identities supplied to one effect invocation.

EffectRuntime

Per-invocation values supplied by the timeline runner.

FrameCost

A frame’s predicted cost in unit pixels per kind of work.

FrameGpuTimes

What the sampled frames of an export measured.

FrameMark

The frame a submission belongs to, as its caller knows it.

FrameSubmissions

How one frame was submitted, as the renderer planned it.

FrameSubmitTimings

Where one frame’s graph construction and submission spent its time.

GpuErrorReports

GPU errors the embedding saw outside the renderer’s scopes (in a browser, all of them).

GpuSubmissionStats

How frames since the last crate::Renderer::take_gpu_submission_stats were split into submissions.

GraphLayer

One owned layer reference in a graph composition node.

InputSpec

An extra image an effect samples, read as sample_<name>(uv) and size_<name>().

LayerTransform

Placement and opacity of one composited layer.

LossClassifier

Classifies a loss by the submission times of its renderer.

Lut3dData

Canonical RGB samples for one cubic 3D lookup table.

LutParseError

Diagnostic returned while parsing .cube text.

MaskCombineNames

Names of one mask’s coverage input and parameters in mask_combine_definition.

PaintParams

Parameter names of one paint in generator_definition.

ParamSpec

One runtime effect parameter.

PassTiming

Most recent timing for one named render pass.

PendingEffect

A runtime effect created on the device, awaiting the device’s verdict.

PendingSourceWork

One source-presentation pass waiting to be encoded by its first consumer.

PipelineCacheStats

Current pipeline-cache occupancy.

PipelineCreation

One pipeline creation for tracing.

PipelineCreationStats

Pipelines this renderer created and the time it took.

PlaneTarget

A caller-owned destination for one packed plane.

PreparedSourceTexture

A rendered source texture plus presentation work its first consumer’s encoder runs.

ReadbackBufferPoolStats

Allocation and retention counters for mapped readback buffers.

RenderCacheKey

Deterministic 128-bit key for a source or rendered graph result.

RenderDiagnostics

Snapshot of render performance, cache, memory, and scheduling behavior.

RenderGraph

An insertion-ordered, acyclic render program.

RenderNodeId

Stable handle to a node within one render graph.

RenderPlan

Compiled execution and lifetime schedule for a render graph.

RenderQualityControls

Quality controls consumed by graph compilation and pass execution.

RenderSize

A non-zero render-target extent.

RenderedTexture

A GPU texture produced by the renderer, storing premultiplied sRGB RGBA (solid clears keep the given values).

Renderer

Renders graphs of sources, effects, transitions and composites on one GPU device, and owns the pipelines, pools and caches they use.

ResourceBudget

Caller-owned resource envelope; zero means the corresponding resource is unavailable.

ResourceSpec

One named external resource required by an effect definition.

ResultCacheStats

Result-cache counters since the renderer was created.

Rgba8Readback

A submitted texture readback whose buffer has not been mapped yet.

ShaderDiagnostic

One schema or WGSL diagnostic.

ShaderDiagnostics

Diagnostics returned when runtime registration fails.

SourcePlane

One borrowed source plane: rows stride bytes apart.

SourcePresentation

GPU presentation transform applied while converting a decoded source.

SourceView

A borrowed source picture: on the GPU a RenderedTexture, an crate::UploadTexture, or (via wgpu interop) any view on the renderer’s device; on the CPU a crate::CpuSource.

StagingPlane

Where one plane sits in a mapped readback staging buffer.

SubmissionReport

The longest recent submission and what it rendered.

TexturePoolStats

Observable allocation counters for the intermediate texture pool.

UniformBufferPoolStats

Allocation and retention counters for submission-scoped uniform arenas.

UniformField

Automatically computed uniform member placement.

UniformLayout

Host layout generated from a parameter schema.

UploadTexture

One source-upload texture retained by the renderer’s descriptor-keyed pool.

UploadTexturePoolStats

Allocation and retention counters for source-upload textures.

WarmupReport

Work completed by a graph warmup request.

Yuv420Frame

Borrowed 8-bit planar 4:2:0 source.

Yuv420pPlanes

Tightly packed planar YUV420 data produced by a GPU readback.

Yuv420pReadback

A submitted GPU RGB-to-YUV420 conversion whose buffer is not mapped yet.

Yuv420pTargets

Destinations for the three planes of one packed frame.

YuvFrame

Borrowed planar or semi-planar YCbCr source of any subsampling and depth YuvFormat::is_supported accepts.

YuvSample

A normalized YUV sample and straight alpha value.

Enums

BlendMode

RGB blend operation applied before Porter-Duff source-over.

BlendSpace

Color space in which compositing arithmetic is evaluated.

CacheEligibility

Whether a node’s result can be cached, and if not, why.

CacheIntent

Whether a node’s result may be kept and reused.

CacheInvalidation

Why cached results were dropped all at once.

CapabilityDiagnostic

One deterministic fallback selected from adapter facts and caller budgets.

ColorDiagnostic

Observable color-pipeline diagnostic.

ColorError

Color conversion failure.

ColorPolicy

What happens to an HDR (PQ or HLG) source.

DiagnosticSeverity

Shader compiler message severity.

EffectKind

Runtime shader category.

EffectResourceKind

Representation an effect resource binding expects from its registered data.

GraphError

Structural or execution failure in a render graph.

ParamType

Host-side parameter representation.

ParamUnit

Semantic unit exposed to authoring hosts.

ParamValue

Typed default parameter value.

ReadbackFailure

Where a texture readback failed.

RenderError

Render input or output failure.

RenderNodeKind

Public category of a render graph node.

SdrOutputTransfer

SDR transfer used when encoding a render result.

SourceAlpha

How an RGBA source texture stores color relative to its alpha.

TimingSource

Source of one pass duration.

Constants

CHROMA_KEY_ID

Stable identifier of the built-in chroma-key effect.

DEFAULT_GPU_WAIT_TIMEOUT

Default native wait for GPU work before giving up.

FILL_PAINT_PARAMS

The fill paint’s parameter names, static so callers need not format them.

GAUSSIAN_BLUR_ID

Stable identifier of the atomic Gaussian-blur effect.

GENERATOR_EFFECT_ID

Internal identifier of the generator pass.

GLOW_ID

Stable identifier of the built-in glow effect.

GPU_DEVICE_LOST_MESSAGE

The message of RenderError::GpuDeviceLost.

GPU_TIMEOUT_MESSAGE

Message every GPU wait timeout carries, so hosts can classify errors from text alone. The message every timed-out GPU wait carries, so hosts that see only error text can classify it as GPU_TIMEOUT.

GPU_WORK_DROPPED_MESSAGE

Message of RenderError::GpuWorkDropped; names a lost device, as hosts classify it.

LUT_3D_ID

Stable identifier of the resource-backed 3D LUT effect.

MASK_COMBINE_EFFECT_IDS

Mask-combine pass ids; the pass for n masks is MASK_COMBINE_EFFECT_IDS[n - 1].

MASK_COMBINE_NAMES

Each mask’s names by index, static so callers need not format them.

MASK_MODES

Enum values of a mask’s mode{i} parameter.

MAX_EFFECT_INPUTS

Most named inputs an effect declares. Source pair, resources and inputs must also fit the device’s sampled textures per stage (16 on WebGL2-class limits), checked at registration.

MAX_GENERATOR_STOPS

Most stops per paint.

MAX_SHAPE_MASKS

Most masks one mask-combine pass takes, each a named input.

PAINT_KINDS

Enum values of a paint’s kind parameter.

PAINT_SPREADS

Enum values of a paint’s spread parameter.

TRACK_MATTE_EFFECT_ID

Internal identifier of the track-matte pass.

Traits

EffectCatalog

Effect information a graph builder needs without drawing. The GPU Renderer and the crate::CpuRenderer answer from the same EffectDefs, so a frame compiles to the same graph on either.

ExternalTextureLease

Keeps an imported native texture and its decoder surface alive until the submission that samples it completes.

RenderControls

Controls a frame runner sets and reads on either renderer.

RgbaPixels

RGBA pixels a source converts from: 8-bit, or half-float bits for linear sources.

YuvPlanes

Decoded YCbCr planes owned by the decoder and kept unchanged while any source holds them.

Functions

blur_sigma_pixels

Standard deviation in pixels of the built-in blur of radius: half the radius, as a fraction of the shorter side.

builtin_catalog

The engine-owned effect catalog as JSON, without shader source.

builtin_catalog_json

Serializes builtin_catalog for process and WebAssembly boundaries.

builtin_effect_definitions

Returns fresh definitions for every public built-in clip effect.

builtin_transition_definitions

Returns fresh, data-only definitions for all built-in transitions.

builtin_wgsl_modules

Every labelled WGSL module the renderer can create: built-in pipelines plus each built-in effect’s and transition’s generated module.

chroma_key_definition

Returns the data-only definition of the built-in chroma-key effect.

convert_yuv_to_linear_rgba

Converts one integer-code-normalized YUV sample to premultiplied linear RGB.

effect_wgsl

The full module compiled for definition: generated preamble plus body.

encode_linear_rgb

Encodes linear-light RGB for an SDR output target.

filter_sample_limit

Most filter samples a pass takes on tier: crate::RenderQualityControls::MAX_FILTER_SAMPLES, or 16 on Tier B (WebGL2, GL ES), whose fill rate cannot keep up with more.

gaussian_blur_definition

Returns the data-only definition of the built-in Gaussian blur.

generator_definition

The generator pass: the fill paint over the whole picture.

glow_definition

Returns the data-only definition of the built-in glow.

is_hdr

Whether color is an HDR signal: PQ or HLG, or declared HDR.

lut_3d_definition

Returns the data-only definition of the resource-backed 3D LUT effect.

mask_combine_definition

The pass combining count masks (1 to MAX_SHAPE_MASKS) into its source’s coverage.

mask_combine_definitions

Every mask-combine pass, for one to MAX_SHAPE_MASKS masks.

pack_cpu_image

Packs picture into layout, one target per plane in storage order (alpha2_media::PixelLayout::planes), as the GPU texel readback does (crate::Yuv420pReadback::finish_into_planes).

resolve_degradation

Resolves deterministic degradation without product- or device-name assumptions.

track_matte_definition

The track-matte pass: keeps the first input where the second’s alpha (or luminance over black, BT.709 weights on linear light times alpha) says, optionally inverted.

yuv420p_staging_bytes

Staging bytes of one planar YUV420 readback of size, including row padding, plane alignment and the 16-byte canary. A budget must reserve this per in-flight readback.