Method addRing

tutorials/tutorial_collisions_finished/main.cpp:268–287

Add a ring to the world, and create a BallJoint constraint to ensure that it stays in a ring shape

  /// Add a ring to the world, and create a BallJoint constraint to ensure that
  /// it stays in a ring shape
  void addRing(const SkeletonPtr& ring)
  {
    setupRing(ring);

    if (!addObject(ring))
      return;

    // Create a closed loop to turn the chain into a ring
    BodyNode* head = ring->getBodyNode(0);
    BodyNode* tail = ring->getBodyNode(ring->getNumBodyNodes() - 1);

    // Compute the offset where the JointConstraint should be located
    Eigen::Vector3d offset = Eigen::Vector3d(0, 0, default_shape_height / 2.0);
    offset = tail->getWorldTransform() * offset;
    auto constraint = std::make_shared<dart::constraint::BallJointConstraint>(
        head, tail, offset);

    mWorld->getConstraintSolver()->addConstraint(constraint);
    mJointConstraints.push_back(constraint);
  }

  /// Remove a Skeleton and get rid of the constraint that was associated with
  /// it, if one existed