module.exports = PointToPointConstraint;
var Constraint = require('./Constraint');
var ContactEquation = require('../equations/ContactEquation');
var Vec3 = require('../math/Vec3');
/**
* Connects two bodies at given offset points.
* @class PointToPointConstraint
* @extends Constraint
* @constructor
* @param {Body} bodyA
* @param {Vec3} pivotA The point relative to the center of mass of bodyA which bodyA is constrained to.
* @param {Body} bodyB Body that will be constrained in a similar way to the same point as bodyA. We will therefore get a link between bodyA and bodyB. If not specified, bodyA will be constrained to a static point.
* @param {Vec3} pivotB See pivotA.
* @param {Number} maxForce The maximum force that should be applied to constrain the bodies.
*
* @example
* var bodyA = new Body({ mass: 1 });
* var bodyB = new Body({ mass: 1 });
* bodyA.position.set(-1, 0, 0);
* bodyB.position.set(1, 0, 0);
* bodyA.addShape(shapeA);
* bodyB.addShape(shapeB);
* world.addBody(bodyA);
* world.addBody(bodyB);
* var localPivotA = new Vec3(1, 0, 0);
* var localPivotB = new Vec3(-1, 0, 0);
* var constraint = new PointToPointConstraint(bodyA, localPivotA, bodyB, localPivotB);
* world.addConstraint(constraint);
*/
function PointToPointConstraint(bodyA,pivotA,bodyB,pivotB,maxForce){
Constraint.call(this,bodyA,bodyB);
maxForce = typeof(maxForce) !== 'undefined' ? maxForce : 1e6;
/**
* Pivot, defined locally in bodyA.
* @property {Vec3} pivotA
*/
this.pivotA = pivotA ? pivotA.clone() : new Vec3();
/**
* Pivot, defined locally in bodyB.
* @property {Vec3} pivotB
*/
this.pivotB = pivotB ? pivotB.clone() : new Vec3();
/**
* @property {ContactEquation} equationX
*/
var x = this.equationX = new ContactEquation(bodyA,bodyB);
/**
* @property {ContactEquation} equationY
*/
var y = this.equationY = new ContactEquation(bodyA,bodyB);
/**
* @property {ContactEquation} equationZ
*/
var z = this.equationZ = new ContactEquation(bodyA,bodyB);
// Equations to be fed to the solver
this.equations.push(x, y, z);
// Make the equations bidirectional
x.minForce = y.minForce = z.minForce = -maxForce;
x.maxForce = y.maxForce = z.maxForce = maxForce;
x.ni.set(1, 0, 0);
y.ni.set(0, 1, 0);
z.ni.set(0, 0, 1);
}
PointToPointConstraint.prototype = new Constraint();
PointToPointConstraint.prototype.update = function(){
var bodyA = this.bodyA;
var bodyB = this.bodyB;
var x = this.equationX;
var y = this.equationY;
var z = this.equationZ;
// Rotate the pivots to world space
bodyA.quaternion.vmult(this.pivotA,x.ri);
bodyB.quaternion.vmult(this.pivotB,x.rj);
y.ri.copy(x.ri);
y.rj.copy(x.rj);
z.ri.copy(x.ri);
z.rj.copy(x.rj);
};