divideScalar

index98
var mousePos = {
    x: .5,
    y: .5
};
document.addEventListener('mousemove', function (event) {
    mousePos = {
        x: event.clientX / window.innerWidth,
        y: event.clientY / window.innerHeight
    };
});
var phase = 0;

var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera(95, window.innerWidth / window.innerHeight, 0.1, 1000);
camera.position.z = 30;

var renderer = new THREE.WebGLRenderer();
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);

var boxSize = 0.2;
var geometry = new THREE.BoxGeometry(boxSize, boxSize, boxSize);
var materialGreen = new THREE.MeshBasicMaterial({
    transparent: true,
    color: 0xff0000,
    opacity: 0.4,
    side: THREE.DoubleSide
});

var pitchSegments = 60;
var elevationSegments = pitchSegments / 2;
var particles = pitchSegments * elevationSegments
var side = Math.pow(particles, 1 / 3);

var radius = 16;

var parentContainer = new THREE.Object3D();
scene.add(parentContainer);

function posInBox(place) {
    return ((place / side) - 0.5) * radius * 1.2;
}

//Plant the seeds, grow some trees in a grid!
for (var p = 0; p < pitchSegments; p++) {
    var pitch = Math.PI * 2 * p / pitchSegments;
    for (var e = 0; e < elevationSegments; e++) {
        var elevation = Math.PI * ((e / elevationSegments) - 0.5)
        var particle = new THREE.Mesh(geometry, materialGreen);

        parentContainer.add(particle);

        var dest = new THREE.Vector3();
        dest.z = (Math.sin(pitch) * Math.cos(elevation)) * radius; //z pos in sphere
        dest.x = (Math.cos(pitch) * Math.cos(elevation)) * radius; //x pos in sphere
        dest.y = Math.sin(elevation) * radius; //y pos in sphere

        particle.position.x = posInBox(parentContainer.children.length % side);
        particle.position.y = posInBox(Math.floor(parentContainer.children.length / side) % side);
        particle.position.z = posInBox(Math.floor(parentContainer.children.length / Math.pow(side, 2)) % side);
        console.log(side, parentContainer.children.length, particle.position.x, particle.position.y, particle
            .position.z)
        particle.userData = {
            dests: [dest, particle.position.clone()],
            speed: new THREE.Vector3()
        };
    }
}

function render() {
    phase += 0.002;
    for (var i = 0, l = parentContainer.children.length; i < l; i++) {
        var particle = parentContainer.children[i];
        var dest = particle.userData.dests[Math.floor(phase) % particle.userData.dests.length].clone();
        var diff = dest.sub(particle.position);
        particle.userData.speed.divideScalar(1.02); // Some drag on the speed
        particle.userData.speed.add(diff.divideScalar(
        400)); // Modify speed by a fraction of the distance to the dest    
        particle.position.add(particle.userData.speed);
        particle.lookAt(dest);
    }

    parentContainer.rotation.y = phase * 3;
    parentContainer.rotation.x = (mousePos.y - 0.5) * Math.PI;
    parentContainer.rotation.z = (mousePos.x - 0.5) * Math.PI;

    renderer.render(scene, camera);
    requestAnimationFrame(render);
}
render();