final int N = this.maxContacts;
DContactBuffer contacts = new DContactBuffer(N);
int n = OdeHelper.collide(o1, o2, N, contacts.getGeomBuffer());
if (n > 0) {
for (int i = 0; i < n; i++) {
DContact contact = contacts.get(i);
contact.surface.mode = this.mode;
contact.surface.mu = this.mu;
contact.surface.bounce = this.bounce;
contact.surface.bounce_vel = this.bounce_vel;
contact.surface.soft_erp = this.soft_erp;