DrawingViewport

Represents a framed orthographic window into a TechnicalDrawing.

Constructors

new DrawingViewport()

new DrawingViewport(config): DrawingViewport

The viewport lives in the drawing's local coordinate system (XZ plane, Y = 0). Its camera must be added as a child of the drawing's container so that any world-space transform applied to the container automatically moves the camera.

The camera uses layer 1 exclusively, so only geometry explicitly assigned to layer 1 (projection lines, dimensions) is visible in paper-space renders.

Local coordinate convention:

• X right → world +X
• Y up (screen) → world -Z
• Normal (out of plane) → world +Y

Parameters

Parameter	Type
config	DrawingViewportConfig

Returns

DrawingViewport

Properties

camera

readonly camera: OrthographicCamera

The Three.js orthographic camera for this viewport. Add it to the drawing container via DrawingViewports.add.

---

name

name: string

Human-readable label for this viewport.

---

onDisposed

readonly onDisposed: Event<void>

Disposable.onDisposed

---

uuid

readonly uuid: string

Unique identifier for this viewport instance.

Accessors

bbox

get bbox(): Box3

Axis-aligned bounding box of this viewport in world drawing space (Y = 0). Used by clipLine and PDF/DXF exporters.

Because screen-up = world −Z, the world Z range visible to the camera is [−top, −bottom], not [bottom, top].

Returns

Box3

---

drawingScale

get drawingScale(): number

Drawing scale denominator (e.g. 100 = 1:100).

Returns

number

---

helper

get helper(): DrawingViewportHelper

The DrawingViewportHelper for this viewport.

The helper is created lazily on first access and cached. It is a THREE.Group on layer 0, so it is visible to the perspective camera but invisible to the viewport's own orthographic camera (layer 1 only).

Use helperVisible to attach/detach it to the drawing container automatically, or manage it manually with drawing.three.add/remove.

Returns

DrawingViewportHelper

---

helperVisible

get helperVisible(): boolean

Shows or hides the DrawingViewportHelper by attaching it to or removing it from the drawing's container group.

Setting this to true before the viewport has been registered via DrawingViewports.add() has no effect until registration occurs.

Returns

boolean

---

localXAxis

get localXAxis(): Vector3

Local X axis direction (world +X).

Returns

Vector3

---

localYAxis

get localYAxis(): Vector3

Local Y axis direction (world -Z).

Returns

Vector3

---

normal

get normal(): Vector3

Drawing plane normal (world +Y).

Returns

Vector3

---

size

get size(): Vector2

Viewport size in millimetres (based on local units × 1000).

Returns

Vector2

Methods

clipLine()

clipLine(line): null | Line3

Clips a line segment to this viewport's bounding box. Returns null when the line is entirely outside the viewport.

Parameters

Parameter	Type
line	Line3

Returns

null | Line3

---

dispose()

dispose(): void

Destroys this viewport. The camera must be removed from its parent separately.

Returns

void

---

setContainer()

Internal

setContainer(container): void

Called by DrawingViewports.add after the viewport is registered. Stores a reference to the drawing container so that helperVisible can attach the helper automatically.

Parameters

Parameter	Type
container	Group<Object3DEventMap>

Returns

void