uē-tôo

Appearance

@ue-too/board / clampByHandler

Function: clampByHandler() ​

clampByHandler(delta, camera, config): Point

Defined in: packages/board/src/camera/camera-rig/pan-handler.ts:536

Handler pipeline step that clamps "pan by" deltas to prevent boundary violations.

Parameters ​

delta ​

Point

Movement delta in world space

camera ​

BoardCamera

Current camera instance (provides boundaries and viewport dimensions)

config ​

PanHandlerClampConfig

Clamping configuration

Returns ​

Point

Adjusted delta that respects boundaries

Remarks ​

This handler ensures that applying the delta won't move the camera outside boundaries. It works by:

  1. Calculating the potential new position (current + delta)
  2. Clamping that position to boundaries
  3. Returning the difference (clamped - current) as the new delta

Behavior depends on configuration:

  • If clampTranslation is false: Returns delta unchanged
  • If limitEntireViewPort is false: Clamps based on camera center
  • If limitEntireViewPort is true: Ensures entire viewport stays in bounds

The resulting delta may be zero if the camera is already at a boundary and trying to move further outside.

Can be used standalone, but typically composed into a handler pipeline via createDefaultPanByHandler or createHandlerChain.

Example ​

typescript
// Standalone usage
camera.position = { x: 1950, y: 500 };
camera.boundaries = { max: { x: 2000 } };

const config: PanHandlerClampConfig = {
  clampTranslation: true,
  limitEntireViewPort: false
};

const delta = { x: 100, y: 0 };  // Try to move right
const clamped = clampByHandler(delta, camera, config);
// Result: { x: 50, y: 0 } - only move to boundary, not beyond

See ​