@techsquidtv/canvas-timeline-core

Binary-searchable timeline snap target index.

The central orchestrator and coordinator for the high-performance timeline editor. Maintains state (tracks, clips, markers, playhead position, zoom scale, scrolls, snaps), builds dynamic snap indexes for magnetic snap guidance, handles split and edit actions, and publishes state events to trigger low-latency canvas renderings and lightweight React layouts.

A general, generic type-safe event emitter class. Extended by components needing typed event publishing and subscription contracts.

Clip that is active at a timeline time, including its mapped source time.

Filters for selecting active clips at a timeline time.

Options for selecting active timeline layers at a timeline time. Use this when integrations need named layers such as `visuals`, `audio`, `subtitles`, or `effects` instead of one flat active-clip list. The same active clip can match more than one layer.

Active timeline layer lookup result. Results include every active clip matched by the requested selectors plus convenience `primary` entries for apps that only need the first match in each layer. Each `ActiveClip` includes mapped source time and source range data for preview and playback synchronization.

Represents an individual media clip node positioned at a specific timeline interval.

Payload emitted by `clip:created` for committed clip creation.

Transient edit-preview state attached to clips while an interaction is active. This state is not intended to be persisted with project data. UI layers can use it to render live editing affordances such as overwrite cut indicators.

Viewport-space pointer query for timeline clip hit testing.

Hit-test result for a clip pointer target.

Keyframe add/update event payload.

Keyframe removal event payload.

Keyframe selection change event payload.

Live clip movement event payload.

Event payload emitted when the playhead enters, updates within, or leaves a clip.

Payload emitted by `clip:removed` for committed clip removal.

Live clip resizing event payload.

Clip selection change event payload.

Live clip slip event payload.

Persistent snap settings for one clip.

Source-media interval covered by a timeline clip.

Payload emitted by `clip:split` for committed clip split.

Viewport-space rectangle for a clip and its containing track.

Central event mapping definition for all engine events.

Undo/redo history state change event payload.

Selection in/out point boundary change event payload.

Represents a bookmark or annotation pin on the timeline's top time ruler.

Marker change event payload (add, remove, update).

Persistent snap settings for one marker.

Options for starting timeline playback.

Controls which built-in timeline boundaries are indexed as magnetic snap targets.

Exact source-frame timestamp returned by a media integration.

App or media-player supplied exact source-frame resolver.

Transient feedback for a live cross-track clip drag.

Flattened clip metadata shared by core geometry APIs, React hooks, and custom renderers.

Options for moving a clip in time and optionally into another track.

Result metadata for a committed or previewed clip move.

Clip entry with viewport geometry and editing/display state.

Cubic Bezier easing control points used by Bezier keyframe interpolation.

Command that removes a timeline range and ripples later clips closed by default.

Range of timeline content affected by an edit command.

Result returned after committing an edit command.

Describes how an active timeline edit affects one clip. This state is transient and is intended for headless UI affordances during live editing interactions. It is not part of the persisted project model.

Active live edit impacts for the current interaction. The model is operation-based so editing modes share the same headless React surface.

App-defined behavioral policy for timeline edit commands.

Context passed to product-defined edit policy callbacks.

Shared preview result produced for every edit command.

Result returned by command validation and policy callbacks.

Command that inserts a new clip and pushes later clips forward.

Canvas-aligned geometry settings for clip hit testing and affordance placement.

One clip-scoped property keyframe positioned at an absolute timeline time.

Options for keyframe curve segment and handle geometry.

Bezier curve handle entry with viewport geometry and edit state.

Viewport-space rectangle for one keyframe curve handle affordance.

Viewport-space pointer query for keyframe curve handle hit testing.

Viewport-space point used by keyframe curve segments and handles.

Keyframe curve segment entry with viewport geometry and optional Bezier handles.

Options for keyframe geometry and hit-testing.

Viewport-space pointer query for timeline keyframe hit testing.

Options for committing or previewing keyframe mutations.

Inputs for mapping a keyframe time/value pair into viewport space.

Keyframe entry with viewport geometry and edit/display state.

Viewport-space rectangle for one keyframe affordance.

Command that removes a timeline range while leaving the gap in place.

Command that moves an existing clip.

Command that places a new clip and removes or trims overlaps on the target track.

Clip placement command shared by insert and overwrite edits.

Command that trims one boundary and ripples later clips on the same track.

Command that rolls the shared boundary between two adjacent clips.

One viewport-space ruler tick for canvas, DOM, or custom rendering.

Options for building shared headless timeline ruler ticks.

Input for creating or upserting a clip keyframe.

Command that moves an existing clip by a relative timeline offset.

Command that shifts an existing clip's source start without moving timeline bounds.

Transient snap feedback consumed by canvas rendering and focused hooks.

Context passed to runtime snap target providers.

Result of resolving a candidate time against the prepared snap index.

One timeline time that can attract an edited boundary.

Represents the complete, serialized state model of the high performance timeline.

Options for building track viewport geometry.

Options for batching row-height updates with related viewport state.

Expanded row height update for a timeline track.

Hit-test result for a timeline track row.

Viewport-space rectangle for a timeline track row.

Command that trims one existing clip boundary.

Input for updating one existing clip keyframe.

Engine-owned constraints for horizontal timeline zoom.

A horizontal timeline lane containing clips and editing state. Tracks are app-owned rows in the timeline model. The engine uses each track's stable id for editing operations, reads the ordered clip list for rendering and hit testing, and honors view/editing flags such as visible, collapsed, locked, and muted.

Track change event payload (add, remove).

Viewport-space pointer query for timeline track hit testing.

Track lock change event payload.

Track mute change event payload.

Track resize event payload.

Track selection change event payload.

Persistent snap settings for one track and its clips.

Track visibility change event payload.

Viewport-intersecting clip entry with clipped timeline and source-media ranges.

Options for building viewport-intersecting clip geometry.

Filters for one named active layer. A layer selector describes the kind of active clips an app wants to drive, such as visual previews, audio playback, subtitles, effects, or a particular source asset. Selectors are matched against the active clips returned for a single timeline time.

Reason a committed engine command created a new clip.

Region of a timeline clip hit by pointer interaction.

Reason a committed engine command removed a clip.

A value that may be available immediately or after asynchronous media lookup.

Clock responsible for advancing playback. Internal playback uses the engine's requestAnimationFrame loop. External playback lets a media player or audio clock drive playhead updates.

Options for building snap targets before a drag, trim, or range-boundary edit.

Source-frame lookup strategy for media integrations.

Reason a clip cannot currently be dropped on a track.

Options for building all clip viewport geometry.

First-class edit command accepted by TimelineEngine edit APIs.

Consequence of an active edit for an affected clip.

Current tool or intent family selected by product editor chrome.

Editing operation that can produce live edit impacts.

Machine-readable reason an edit command cannot be resolved or committed.

Hit-test result for a keyframe curve handle pointer target.

Bezier control handle edited by a curve interaction.

Hit-test result for a timeline keyframe pointer target.

Segment interpolation mode used from one keyframe to the next.

First-party clip property that can be animated with timeline keyframes.

Label style used by timeline ruler ticks.

Ruler tick visual weight.

Timeline interaction currently preparing or resolving snap targets.

Runtime source of app-defined snap targets such as grids, beats, and captions.

Built-in and application-defined magnetic snap target categories.

Viewport-intersecting keyframe entry.

Viewport-intersecting keyframe curve segment.

Default ease-in-out curve used when a Bezier keyframe omits easing control points.

Geometry defaults shared by canvas-aligned interaction layers.

Default zoom-in density when a frame rate constrains timeline zoom.

Creates a sanitized marker array for timeline state and history snapshots.

Evaluates a Cubic Bezier easing curve at normalized time progress.

Returns viewport-space cubic Bezier control points between two keyframe points.

Evaluates normalized segment progress for a keyframe interpolation mode.

Maps one keyframe value to the same viewport point used by canvas drawing and DOM handles.

Builds shared viewport-space ruler ticks for canvas, DOM, and custom renderers.

Validates and clamps Cubic Bezier control points to the timeline interpolation domain.

Normalizes a keyframe interpolation mode. Unknown or omitted values are treated as linear.

Shifts all keyframes on a clip by a timeline delta.