FabricOverlay
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:40
A Fabric.js canvas overlay synchronized with an OpenSeaDragon viewer.
Handles event routing between OSD and Fabric using an OSD MouseTracker attached to Fabric’s container element. Events are forwarded to Fabric as synthetic PointerEvents with a re-entrancy guard to prevent infinite recursion (dispatched events bubble back to the tracker’s element).
Two interaction modes:
- navigation: OSD handles all input, Fabric is display-only.
- annotation: Fabric handles all input (select, move, draw). Ctrl+drag or Command+drag pans OSD within annotation mode.
Constructors
Section titled “Constructors”Constructor
Section titled “Constructor”new FabricOverlay(
viewer,options?):FabricOverlay
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:65
Parameters
Section titled “Parameters”viewer
Section titled “viewer”Viewer
options?
Section titled “options?”Returns
Section titled “Returns”FabricOverlay
Accessors
Section titled “Accessors”canvas
Section titled “canvas”Get Signature
Section titled “Get Signature”get canvas():
Canvas
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:67
The Fabric.js Canvas instance
Returns
Section titled “Returns”Canvas
Methods
Section titled “Methods”applyImageFilters()
Section titled “applyImageFilters()”applyImageFilters(
exposure,inverted):void
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:72
Parameters
Section titled “Parameters”exposure
Section titled “exposure”number
inverted
Section titled “inverted”boolean
Returns
Section titled “Returns”void
applyViewTransform()
Section titled “applyViewTransform()”applyViewTransform(
transform):void
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:69
Apply a view transform (rotation/flip) to the OpenSeadragon viewer
Parameters
Section titled “Parameters”transform
Section titled “transform”Returns
Section titled “Returns”void
destroy()
Section titled “destroy()”destroy():
void
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:92
Clean up all event listeners and DOM elements
Returns
Section titled “Returns”void
getFlip()
Section titled “getFlip()”getFlip():
boolean
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:71
Returns
Section titled “Returns”boolean
getMode()
Section titled “getMode()”getMode():
OverlayMode
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:86
Get the current overlay interaction mode
Returns
Section titled “Returns”getRotation()
Section titled “getRotation()”getRotation():
number
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:70
Returns
Section titled “Returns”number
imageToScreen()
Section titled “imageToScreen()”imageToScreen(
imagePoint):Point
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:90
Convert a point from image-space to screen-space
Parameters
Section titled “Parameters”imagePoint
Section titled “imagePoint”Returns
Section titled “Returns”resetView()
Section titled “resetView()”resetView():
void
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:73
Returns
Section titled “Returns”void
screenToImage()
Section titled “screenToImage()”screenToImage(
screenPoint):Point
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:88
Convert a point from screen-space to image-space
Parameters
Section titled “Parameters”screenPoint
Section titled “screenPoint”Returns
Section titled “Returns”setMode()
Section titled “setMode()”setMode(
mode):void
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:84
Set the overlay interaction mode
Parameters
Section titled “Parameters”Returns
Section titled “Returns”void
sync()
Section titled “sync()”sync():
void
Defined in: packages/fabric-osd/dist/overlay/fabric-overlay.d.ts:82
Force a re-sync of the overlay transform with the current OSD viewport.
Uses synchronous renderAll() because this runs inside OSD’s own requestAnimationFrame callback. Using the async requestRenderAll() would defer the Fabric paint to the next frame, causing a visible 1-frame lag where the image has moved but annotations haven’t.
Returns
Section titled “Returns”void