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@ue-too/board / BoardCamera

Interface: BoardCamera

Defined in: packages/board/src/camera/interface.ts:85

Core camera interface for the infinite canvas board system. Manages camera position, rotation, zoom, and coordinate transformations between viewport and world space.

The camera uses a center-anchored coordinate system where the camera position represents the center of the viewport in world coordinates.

Remarks

Transformation order: Scale (devicePixelRatio) → Translation (viewport center) → Rotation → Zoom → Translation (camera position)

Example

typescript
const camera: BoardCamera = new BaseCamera(1920, 1080);
camera.setPosition({ x: 100, y: 100 });
camera.setZoomLevel(2.0);
camera.setRotation(Math.PI / 4); // 45 degrees

// Convert mouse position to world coordinates
const worldPos = camera.convertFromViewPort2WorldSpace(mousePos);

Extended by

Properties

boundaries?

optional boundaries: Boundaries

Defined in: packages/board/src/camera/interface.ts:102

Optional position boundaries for the camera in world coordinates


position

position: Point

Defined in: packages/board/src/camera/interface.ts:87

Current camera position in world coordinates (center of viewport)


rotation

rotation: number

Defined in: packages/board/src/camera/interface.ts:90

Current rotation in radians (0 to 2π), normalized


rotationBoundaries?

optional rotationBoundaries: RotationLimits

Defined in: packages/board/src/camera/interface.ts:108

Optional rotation constraints (start and end angles)


viewPortHeight

viewPortHeight: number

Defined in: packages/board/src/camera/interface.ts:99

Height of the viewport in CSS pixels


viewPortWidth

viewPortWidth: number

Defined in: packages/board/src/camera/interface.ts:96

Width of the viewport in CSS pixels


zoomBoundaries?

optional zoomBoundaries: ZoomLevelLimits

Defined in: packages/board/src/camera/interface.ts:105

Optional zoom level constraints (min and max zoom)


zoomLevel

zoomLevel: number

Defined in: packages/board/src/camera/interface.ts:93

Current zoom level (1.0 = 100%, 2.0 = 200%, etc.)

Methods

convertFromViewPort2WorldSpace()

convertFromViewPort2WorldSpace(point): Point

Defined in: packages/board/src/camera/interface.ts:221

Converts a point from viewport coordinates to world coordinates.

Parameters

point

Point

Point in viewport space (pixels from viewport center)

Returns

Point

Corresponding point in world coordinates

Example

typescript
// Convert mouse position (relative to viewport center) to world position
const mouseViewport = { x: mouseX - canvas.width/2, y: mouseY - canvas.height/2 };
const worldPos = camera.convertFromViewPort2WorldSpace(mouseViewport);

convertFromWorld2ViewPort()

convertFromWorld2ViewPort(point): Point

Defined in: packages/board/src/camera/interface.ts:235

Converts a point from world coordinates to viewport coordinates.

Parameters

point

Point

Point in world coordinates

Returns

Point

Corresponding point in viewport space (pixels from viewport center)

Example

typescript
// Find viewport position of a world object
const viewportPos = camera.convertFromWorld2ViewPort(objectWorldPos);

getTransform()

getTransform(devicePixelRatio, alignCoordinateSystem): object

Defined in: packages/board/src/camera/interface.ts:272

Calculates the complete transformation matrix for rendering. This matrix transforms from world space to canvas pixel space.

Parameters

devicePixelRatio

number

Device pixel ratio for high-DPI displays (typically window.devicePixelRatio)

alignCoordinateSystem

boolean

If true, uses standard coordinate system (y-up). If false, uses inverted y-axis

Returns

object

2D transformation matrix in standard form

a

a: number

b

b: number

c

c: number

d

d: number

e

e: number

f

f: number

Remarks

Apply this matrix to canvas context: ctx.setTransform(a, b, c, d, e, f) The transformation includes devicePixelRatio scaling, viewport centering, rotation, zoom, and camera position.

Example

typescript
const transform = camera.getTransform(window.devicePixelRatio, true);
ctx.setTransform(transform.a, transform.b, transform.c, transform.d, transform.e, transform.f);
// Now draw in world coordinates

getTRS()

getTRS(devicePixelRatio, alignCoordinateSystem): object

Defined in: packages/board/src/camera/interface.ts:244

Decomposes the camera transformation into Translation, Rotation, and Scale components.

Parameters

devicePixelRatio

number

Device pixel ratio for high-DPI displays

alignCoordinateSystem

boolean

If true, uses standard coordinate system (y-up). If false, uses inverted y-axis

Returns

object

Object containing separate scale, rotation, and translation values

rotation

rotation: number

scale

scale: object

scale.x

x: number

scale.y

y: number

translation

translation: object

translation.x

x: number

translation.y

y: number


setHorizontalBoundaries()

setHorizontalBoundaries(min, max): void

Defined in: packages/board/src/camera/interface.ts:195

Sets horizontal (x-axis) movement boundaries for the camera.

Parameters

min

number

Minimum x coordinate in world space

max

number

Maximum x coordinate in world space

Returns

void

Remarks

If min > max, values are automatically swapped.


setMaxZoomLevel()

setMaxZoomLevel(maxZoomLevel): void

Defined in: packages/board/src/camera/interface.ts:184

Updates the maximum allowed zoom level.

Parameters

maxZoomLevel

number

Maximum zoom level constraint

Returns

void


setMinZoomLevel()

setMinZoomLevel(minZoomLevel): void

Defined in: packages/board/src/camera/interface.ts:177

Updates the minimum allowed zoom level.

Parameters

minZoomLevel

number

Minimum zoom level constraint

Returns

void

Remarks

If current zoom is below the new minimum, camera will zoom in to match the minimum.


setPosition()

setPosition(destination): boolean

Defined in: packages/board/src/camera/interface.ts:145

Sets the camera position in world coordinates.

Parameters

destination

Point

Target position for the camera center

Returns

boolean

True if position was updated, false if rejected by boundaries or no significant change

Remarks

Position changes smaller than 10E-10 or 1/zoomLevel are ignored to prevent floating-point jitter. Position is clamped to boundaries if set.


setRotation()

setRotation(rotation): boolean

Defined in: packages/board/src/camera/interface.ts:167

Sets the camera rotation in radians.

Parameters

rotation

number

Target rotation angle in radians

Returns

boolean

True if rotation was updated, false if outside boundaries or already at limit

Remarks

Rotation is automatically normalized to 0-2π range. Clamped to rotationBoundaries if set.


setVerticalBoundaries()

setVerticalBoundaries(min, max): void

Defined in: packages/board/src/camera/interface.ts:206

Sets vertical (y-axis) movement boundaries for the camera.

Parameters

min

number

Minimum y coordinate in world space

max

number

Maximum y coordinate in world space

Returns

void

Remarks

If min > max, values are automatically swapped.


setZoomLevel()

setZoomLevel(zoomLevel): boolean

Defined in: packages/board/src/camera/interface.ts:156

Sets the camera zoom level.

Parameters

zoomLevel

number

Target zoom level (1.0 = 100%)

Returns

boolean

True if zoom was updated, false if outside boundaries or already at limit

Remarks

Zoom is clamped to zoomBoundaries if set. Values are clamped, not rejected.


viewPortAABB()

viewPortAABB(alignCoordinate?): object

Defined in: packages/board/src/camera/interface.ts:119

Calculates the axis-aligned bounding box (AABB) of the viewport in world space.

Parameters

alignCoordinate?

boolean

If true, uses standard coordinate system (y-up). If false, uses inverted y-axis

Returns

object

Object with min and max points defining the bounding box

max

max: Point

min

min: Point

Remarks

Useful for culling and determining which objects are visible in the current viewport.


viewPortInWorldSpace()

viewPortInWorldSpace(alignCoordinate?): object

Defined in: packages/board/src/camera/interface.ts:130

Calculates the four corners of the viewport in world space, accounting for rotation.

Parameters

alignCoordinate?

boolean

If true, uses standard coordinate system (y-up). If false, uses inverted y-axis

Returns

object

Object containing the four corner points (top-left, top-right, bottom-left, bottom-right)

bottom

bottom: object

bottom.left

left: Point

bottom.right

right: Point

top

top: object

top.left

left: Point

top.right

right: Point

Remarks

Returns the actual rotated viewport corners, not an AABB. Use this for precise viewport bounds.