Crate alpha2_eval

Expand description

Pure, deterministic timeline evaluation.

Structs§

ActiveAudioClip: One audio clip overlapping an evaluated timeline span.
ActiveCaption: The cue one caption track shows at a timestamp.
ActiveClip: A visible or audible clip mapped to its source timestamp.
ActiveComposition: A clip’s composition at one timeline timestamp.
ActiveEffect: One effect invocation at one timestamp: timeline time for a timeline transition, composition time for a composition step.
ActiveIndex: A precomputed interval index for a validated project snapshot.
ActiveTransition: A transition evaluated at one timeline timestamp.
AudioSpan: The clips of one span, as evaluate_audio reports them, held in an AudioSpanScratch and read back without copying.
AudioSpanDesc: Audio activity over one half-open timeline span.
AudioSpanScratch: Reusable working memory for evaluate_audio_in.
CompositionPlan: A composition’s output, drawn by steps in dependency order.
EffectParamValue: One effect parameter’s value at a timeline timestamp.
EvaluatedVisual: Visual properties evaluated at one timeline timestamp.
FrameDesc: A timestamp-specific composition description with no GPU handles.
FrameNeed: A source-frame request emitted for host prefetch and decode scheduling.
Step: One node of a composition, with its inputs resolved to earlier steps.
StepLayer: One layer of a StepOp::Merge.

MAX_PLAN_BYTES: Most bytes the compiled composition plans of one project hold together, as Steps estimate them: each step, its node path, and the heap its settings use (keyframes, parameter and resource names, masks, layers, gradient stops). A project’s plans are those of every composition a clip or composition source shows; past this, none of them is drawn (PlanError::TooLarge). The steps are what validation counts, at most MAX_INLINED_NODES; this bounds how large each may be, which inlining multiplies.

evaluate: Evaluates visual and audio clip descriptions at one timeline timestamp.
evaluate_audio: Evaluates every audible clip overlapping a half-open timeline span.
evaluate_audio_in: Evaluates the same clips as evaluate_audio into reusable memory.
frame_needs: Describes all source frames needed at a timestamp.
picture_source_time: The source instant a clip’s picture shows at timeline time: its time map read with the reverse and ping-pong mirror of one project frame at frame_rate, exactly as evaluation draws it.
plan_composition: Compiles composition’s output into steps, as a clip’s composition: its clip nodes draw the clip’s picture. compositions resolves group nodes and sources media nodes, which may name generated or composition sources.
plan_source_composition: Compiles composition as a composition source draws it: like plan_composition, but a clip node or group input is an error, since no clip or group node feeds it.
sample_effect_param: Samples one effect parameter with the project’s keyframe semantics.
sample_scalar: Samples one animated scalar with the project’s keyframe semantics.
sample_vec2: Samples one animated two-dimensional value with the project’s keyframe semantics; see sample_scalar.
sample_visual: Evaluates visual properties at a timestamp: a clip’s at timeline time, a transform node’s at composition time.