Discreet is shipping Reactor, an integrated extension for 3DS Max 4. Reactor adds real-time physics that realistically simulates cloth, rope, liquid, and hard/soft-body objects that can collide, bounce, break, and stretch. Reactor is powered by Havok - the same company behind the physics engine in the just-announced Macromedia Director 8.5. Pitched at games developers, film and video producers, and Web designers, Reactor includes a real-time dynamic simulation viewer. Game developers can integrate a dynamic library directly into a game title, says Discreet. Features include rope dynamics that can simulate chains, rope, and hair; cloth dynamics that give objects elasticity; and rigid and soft-body dynamics that can create objects such as collapsing walls to landslides. Pricing has yet to be released.