Elastic collision

[mgrzeszczak]

Is there a way to change the elasticity of collision, meaning how much energy is lost on impact? For example when hitting two sphere bodies, they lose most of their energy.

[amusaafir]

Check out the restitution property in the ContactMaterial class. Set the value of this property to e.g., 1.0 to achieve the effect you're looking for.

[lorankary]

I have the same problem. I have colliding spheres and I want no energy lost on collisions. I set the restitution to 1.0 but still the energy is lost. Any thoughts that might help?

var physicsMaterial = new CANNON.Material("bouncyMaterial");
var physicsContactMaterial = new CANNON.ContactMaterial(physicsMaterial,
                                                        physicsMaterial,
                                                        0.0, // friction coefficient
                                                        1.0  // restitution
                                                        );
// We must add the contact materials to the world
world.addContactMaterial(physicsContactMaterial);

... this.body = new CANNON.Body({ mass: this.mass, position: new CANNON.Vec3(this.loc.x, this.loc.y, 0), // m shape: new CANNON.Sphere(this.radius), velocity: new CANNON.Vec3(this.vel.x, this.vel.y, 0), linearDamping: 0, material: physicsMaterial });

[DiuDono]

I tried it with a cube moving along y axis between two boxes. The cube starts spinning after a few collisions. That explains why it loses energy.