Crate alpha2_engine 

Player and exporter public API.

wgpu interop

The default API names no wgpu type: hosts lend frames as alpha2_render::SourceViews through FrameProvider and get back alpha2_render::RenderedTextures and readbacks. Items taking wgpu textures (such as rendering into hardware encoder NV12 planes) are documented only with the wgpu-interop feature and follow wgpu’s major version.

Re-exports

pub use frame::FrameGraph;

pub use frame::FrameProvider;

pub use frame::FrameRender;

pub use frame::FrameRenderer;

pub use frame::FrameYuv420pRender;

pub use frame::GpuFrameRenderer;

pub use frame::RenderReport;

pub use frame::check_frame_effects;

Structs

AudioNeed

A source interval a host decodes before a render reads it.

AudioRenderStatus

Outcome of mixing one block.

AudioRenderer

Mixes a project’s audio tracks into one project-rate block.

Baselines

A text’s first and last alphabetic baselines, as fractions of the canvas (or picture) height, y down.

CanvasRect

A rectangle as fractions of the canvas, y down.

CapabilityReport

What a runtime can do.

ClockStep

What the clock asks for at one moment.

ColorReport

How color is handled.

EngineProject

An immutable project snapshot and its reusable evaluation index.

ExportAudioWindow

The project-rate samples an export’s audio covers.

ExportFrameNeeds

Decode requirements for one scheduled export frame.

ExportProgress

Completed and total frame counts for deterministic export.

ExportStepTimings

Where one Exporter::render_next_timed step spent its time.

Exporter

Deterministic, retryable frame-sequence runner.

Feature

One feature: whether it is available, and why not.

FrameGraph

One evaluated frame compiled into a render graph, not yet submitted.

FrameRender

Result of attempting to render one evaluated timeline frame.

FrameYuv420pRender

Result of rendering and scheduling one frame for planar YUV420 readback.

FramesWithText

A host’s frame provider combined with its text store.

GpuMemoryReport

The device memory the adapter may use.

GpuReport

The GPU the renderer drives.

LayoutBounds

Where a layout’s nodes lie (measure_layout), in preorder.

NodeBounds

Where one layout node’s boxes lie, before its clip’s transform and node visuals.

PassthroughPlan

What an export range copies: its segments in timeline order, and its audio.

PassthroughSegment

One clip’s share of a copied range.

PictureSize

The size in pixels of a picture text and layouts are placed on. Never empty, and within the largest frame the engine draws (alpha2_media::MAX_FRAME_DIMENSION, alpha2_media::MAX_FRAME_PIXELS).

PlaybackClock

The clock for one playback run, asked each display refresh which time to show.

PlaybackFrame

Result of one real-time presentation attempt; I is FrameRenderer::Image.

PlaybackReport

How real-time playback behaves.

Player

Stateful real-time runner holding the last picture drawn. I is FrameRenderer::Image: a RenderedTexture on the GPU or an Arc<CpuImage> on the alpha2_render::CpuRenderer.

PreparedLayout

A layout resolved at one render size: its paint list and each text node’s texture key.

QualityProfile

Runtime quality controls shared by real-time playback and export.

RenderReport

Outcome of one render attempt when sources may arrive asynchronously.

TextBounds

Where a text lies, as fractions of the canvas from (0, 0) top-left to (1, 1) bottom-right. For a text generator this is on its picture, before the clip’s transform and effects; for a caption it is on the canvas.

TextPixels

The pixels of one prepared text.

TextTexture

One prepared text: its texture, pixel size and layout box position.

TextTextures

Fonts and the texts rasterized with them, keyed by content and render size.

Enums

AudioContinuity

What AudioRenderer::render does with a block that does not start where the previous one ended.

EngineError

Failure produced by an engine runner.

ErrorCode

A failure’s protocol code.

ExportPlaneStep

One step of an export that packs its picture straight into caller-owned planes.

ExportStep

Outcome of one non-blocking exporter step.

ExportTextureStep

One step of an export that leaves its picture as a rendered texture.

MissingFramePolicy

The action a host should take after its renderer reports missing frames.

PassthroughAudio

What an export’s audio is over a copied range: copied too, or encoded from the mix.

PictureSizeError

Why a size is not a PictureSize.

PlaybackPolicy

Which frame real-time playback shows, and whether sound plays.

Runtime

Where the engine runs.

TextError

Why text could not be prepared.

Constants

CAPABILITY_SCHEMA

The report’s schema name.

CAPABILITY_VERSION

The report’s schema version.

LAYOUT_WRAP_SLACK

Pixels added to a text node’s wrapping width so float summation order cannot re-break a text sized to its own max-content width. Lines and heights may overflow the box by less than this.

MAX_AUDIO_BLOCK

Largest block a renderer will mix in one call.

MAX_EXPORT_FRAMES

Largest frame schedule accepted by one export operation.

MAX_SETTLING_SECONDS

Longest a stage replays to settle before a seek target, in seconds.

Traits

FrameProvider

Supplies decoded source frames as GPU textures to the renderer.

FrameRenderer

Timeline-frame rendering on the GPU Renderer or the alpha2_render::CpuRenderer. GPU-only readback and encoder paths are in GpuFrameRenderer.

GpuFrameRenderer

GPU frame paths that end on the GPU: an unmapped YUV420 readback or encoder NV12 planes.

TextUpload

Where TextTextures keeps rasterized pixels: a GPU texture or CPU memory.

Functions

check_frame_effects

Checks that renderer draws every effect frame uses, naming the first missing one (unlike the RenderError that FrameRenderer returns).

color_policy

The renderer’s color policy: tone-map HDR sources from the project peak, or refuse them.

export_audio_window

The audio samples an export over range writes: each end is the nearest sample, halves rounding up.

gpu_error_of

The GPU error class of the first RenderError::Gpu in error’s source chain. Out of memory and validation have no protocol code; failure reports classify them with this.

gpu_fault_of

The device fault reported for the first failed GPU call in error’s source chain (renderer synchronization, decoder or encoder). Failure reports classify memory faults with this.

layout_key

A layout’s identity at a render size. Equal keys draw alike with the same fonts.

measure_layout

Where each node of a valid layout tree lies on a picture of size at picture time time, laid out with rasterizer’s fonts exactly as a frame is.

measure_text

Where text in style lies on a canvas of size, laid out with rasterizer’s fonts and placed exactly as a frame places it, without drawing it.

passthrough_plan

Whether range of project shows its sources untouched.

text_key

A text’s identity at a render size: the text, its style and the size, hashed with FNV-1a. Never zero.