import { FusionSurfaceGeometry, FusionSurfaceGeometryInput } from './types';
/** Pinch at which a neck counts as broken: the waist is 1.5% of the bud's
 *  half-width, about a pixel for a 160px bud. The component latches the split
 *  there; a caller driving `fusionSurfacePath()` itself should too. */
export declare const FUSION_SURFACE_BREAK_PINCH = 0.985;
/**
 * The default neck: nothing for the first quarter of `breakAt`, then the
 * square of a smoothstep, fully closed at `breakAt` (it snaps at about 96%).
 *
 * Squared, the curve starts with zero slope and zero curvature and stays
 * small until the neck has stretched about half of `breakAt`, then closes
 * quickly, the way a stretched liquid bridge gives way late.
 */
export declare function fusionSurfacePinch(detach: number, breakAt: number): number;
/**
 * The surface as one SVG path `d`: the body (unless `includeBody` is false),
 * every attached bud or neck merged into the body's outline, and every drop
 * as its own closed subpath. Also returns where each attached shape meets the
 * body (`spans`) and each bud's current outer box (`rects`).
 *
 * Buds on one edge must not overlap. Out-of-range or non-finite numbers
 * degrade to not drawing the bud; the output never contains NaN or Infinity.
 */
export declare function fusionSurfacePath(input: FusionSurfaceGeometryInput): FusionSurfaceGeometry;