import { vec2 } from 'gl-matrix';
import { BodyInterface, ConstraintClamping, WorldInterface } from '../types';
import { ConstraintBase } from './constraint.base';
export declare class FrictionConstraint extends ConstraintBase {
    readonly world: WorldInterface;
    readonly bodyA: BodyInterface;
    readonly bodyB: BodyInterface;
    readonly joint: vec2;
    readonly normal: vec2;
    readonly mu: number;
    constructor(world: WorldInterface, bodyA: BodyInterface, bodyB: BodyInterface, joint: vec2, normal: vec2, // normal at bodyA
    mu: number);
    getJacobian(out: Float32Array): void;
    getPushFactor(): number;
    getClamping(): ConstraintClamping;
    patch(point: vec2, normal: vec2): void;
}