P2: Constant movement without losing velocity

[finspin]

How could I make ball bouncing off the world borders constantly? I tried to play around with contactMaterial properties but nothing seems to do the job. The ball will slowly lose its velocity.

 

I'd like it to bounce constantly with constant velocity.

var game = new Phaser.Game(480, 640, Phaser.AUTO, 'Bubble Game', {    preload: preload,    create: create,    update: update,    render: render});var bubble1;function preload() {    game.load.image('bubble1', 'assets/bubble1.png');//    game.load.image('bubble2', 'assets/bubble2.png');//    game.load.image('bubble3', 'assets/bubble3.png');}function create() {    game.stage.backgroundColor = "#000";    game.physics.startSystem(Phaser.Physics.P2JS);    bubble1 = game.add.sprite(game.world.centerX, game.world.centerY, 'bubble1');    game.physics.p2.enable(bubble1);    bubble1.body.setCircle(50);    var bubbleMaterial = game.physics.p2.createMaterial('bubbleMaterial', bubble1.body);    var worldMaterial = game.physics.p2.createMaterial('worldMaterial');    game.physics.p2.setWorldMaterial(worldMaterial, true, true, true, true);    var contactMaterial = game.physics.p2.createContactMaterial(bubbleMaterial, worldMaterial);    contactMaterial.friction = 0;    contactMaterial.restitution = 1.0;    contactMaterial.stiffness = 0;    contactMaterial.relaxation = 0;    contactMaterial.frictionStiffness = 0;    contactMaterial.frictionRelaxation = 0;    contactMaterial.surfaceVelocity = 0;    bubble1.body.velocity.x = 200;    bubble1.body.velocity.y = 200;}function update() {}function render() {}

[quarks]

You need to set the damping value on the body to 0.

bubble1.body.damping = 0;

[finspin]

That did it, great, thanks!