API overview

Three packages. core is the only one that is required.

Package	Contents	Runtime dependencies
@headless-canvas/core	Editor, shapes, state, transforms, tools, control primitives	None
@headless-canvas/ui	Default controls, stylesheet, clipboard binding	core
@headless-canvas/react	React bindings	core, ui, react

@headless-canvas/core

Area	Exports
Editor	Editor, EditorOptions, CreateShapeInput, ZIndexAnchor
Controls	Controls, HandleId, HandleDescriptor, SelectionBoxDescriptor, A11yShapeDescriptor, RESIZE_HANDLES
Shapes	ShapeUtil, ShapeUtilRegistry, ShapeRegistry, ShapeBase, AnyShape, ShapeId, ZIndex, asShapeId, asZIndex, RenderInfo, the seven built-in *ShapeUtils, defaultShapeUtils
Shape props	RectProps, EllipseProps, LineProps, PathProps, TextProps, ImageProps, GroupProps, Fill, Stroke, Shadow, PaintProps, GradientStop
Painting	resolveFill, applyStrokeStyle, applyShadow, paintPath, fontString
Geometry	pointInPolygon, distanceToSegment, distanceToPolyline, parsePath, emitPath, pathData, flattenPath, pathBounds, simplifyPolyline, polylineToPath, PathCommand, PathSink
Maths	Vec, Bounds, OrientedBounds, Matrix and their operations
Viewport	Camera, screenToWorldPoint, worldToScreenPoint, cameraMatrix, visibleBounds, clampZoom, DEFAULT_ZOOM_RANGE
Transforms	decomposeTransform, worldTransformOf, worldCorners, inheritedOpacity
State	Store, StoreSnapshot, TransactOptions, CommitEvent, Patch, invertPatch, invertPatches
History	History, HistoryEntry, HistoryOptions
Documents	HcDocument, SCHEMA_VERSION, serialize, deserialize, SerializeOptions, DeserializeResult
Rendering	Renderer, RenderItem, RenderScene, Canvas2dRenderer, worldAabb, exportToBlob, ExportOptions, HcTaintedCanvasError
SVG export	exportToSvg, SvgExportOptions, SvgExportParams, SvgNode, SvgRenderInfo
Resources	ResourceCache, ResourceCacheOptions, ResourceStatus, ResourceRequest
Tools	Tool, ToolState, HcPointerEvent, SelectTool, HandTool, DrawTool, DrawToolOptions, defaultDrawOptions, strokeFromPoints, StrokeGeometry
Snapping	SnapSettings, SnapGuide, SnapResult, defaultSnapSettings
Notifications	Notification, NotificationEmitter
i18n	Messages, defaultMessages, formatMessage
Utilities	createId, RTree, SpatialIndex, compareIndexes, generateIndexBetween, generateNIndexesBetween, DEV

@headless-canvas/ui

function createDefaultControls(
  editor: Editor,
  options?: { accessibleList?: boolean },
): { dispose(): void }

function createClipboardBinding(
  editor: Editor,
  options?: ClipboardBindingOptions,
): ClipboardBinding

function createTextEditor(
  editor: Editor,
  options?: { submitOnEnter?: boolean },
): { dispose(): void }

Plus the stylesheet, imported from its own subpath so it is never injected at runtime:

import '@headless-canvas/ui/styles.css'

The class names and data attributes it defines are public API — see the CSS contract.

@headless-canvas/react

See the React reference.

Stability

Everything on these pages follows semver from v1.0. So does the CSS contract: renaming a class or a data attribute is a breaking change, exactly as renaming a method would be.

Anything not documented here is internal, whatever its export status.

During the 0.x series, minor versions may contain breaking changes; they will be listed in the changelog.