math-examples.test.js

var expect = require('chai').expect;
var ROSLIB = require('..');

function clone(x) {
    var y = {};
    for (var prop in x) {
        if (x.hasOwnProperty(prop)) {
            y[prop] = typeof x[prop] === "object" ? clone(x[prop]) : x[prop];
        }
    }
    return y;
}

describe('Math examples', function() {
    var v1, q1, v2, q2;
    var pos;
    it('Vector3 example', function() {
        // Let's start by adding some vectors.
        v1 = new ROSLIB.Vector3({
            x: 1,
            y: 2,
            z: 3
        });
        v2 = v1.clone();
        expect(v1).not.equal(v2);
        expect(v1).eql(v2);

        v1.add(v2);
        expect(clone(v1)).eql({
            x: 2,
            y: 4,
            z: 6
        });
    });

    it('Quaternion example', function() {
        // Now let's play with some quaternions.
        q1 = new ROSLIB.Quaternion({
            x: 0.1,
            y: 0.2,
            z: 0.3,
            w: 0.4
        });
        q2 = q1.clone();
        expect(q1).not.equal(q2);
        expect(q1).eql(q2);

        q1.multiply(q2);
        q1.invert();
        expect(q1.x).to.be.within(-0.26667, -0.26666);
        expect(q1.y).to.be.within(-0.53334, -0.53333);
        expect(q1.z).to.be.within(-0.80000, -0.79999);
        expect(q1.w).to.be.within(0.06666, 0.06667);
    });

    it('Pose example', function() {
        // Let's copy the results into a pose.
        pos = new ROSLIB.Pose({
            position: v1,
            orientation: q1
        });
        expect(clone(pos)).to.eql(clone({position: v1, orientation: q1}));
    });

    it('Transform example', function() {
        // Finally, let's play with some transforms.
        var tf = new ROSLIB.Transform({
            translation: v2,
            rotation: q2
        });
        pos.applyTransform(tf);
        expect(pos.orientation.x).to.be.within(-0.1, -0.09999);
        expect(pos.orientation.y).to.be.within(-0.20001, -0.20000);
        expect(pos.orientation.z).to.be.within(-0.3, -0.3);
        expect(pos.orientation.w).to.be.within(0.39999, 0.4);

        expect(pos.position.x).to.be.within(1.6, 1.60001);
        expect(pos.position.y).to.be.within(3.2, 3.20001);
        expect(pos.position.z).to.be.within(4.8, 4.80001);
    });
});