export type Callback = (value: number) => void; export interface Options { mass?: number; tension?: number; friction?: number | null; precision?: number; initialValue?: number; velocity?: number; targetValue?: number; onStart?: Callback | null; onUpdate?: Callback | null; onEnd?: Callback | null; } export type Preset = { mass: number; tension: number; friction?: number; }; export type PresetName = 'gentle' | 'wobbly' | 'stiff' | 'slow' | 'molasses';