Physics Constraints

This section will discuss physics constraints. First an overview is given followed by a hands-on example where you tie several objects together and apply a force to see how those tied objects react.

Physics Constraints Overview

Physics constraints are objects that can be used to bind together different objects. Physics constraints are very flexible and have many options that can specify exactly how objects are to be tied together. With a physics constraint you can bind one actor to another or to the world itself by specifying None for that actor. If constraining a skeletal mesh you can specify which bone name to bind to.

For example, an arrow attached to a string that when fired from a bow will allow the user to retract the arrow and retrieve whatever the arrow has penetrated. The arrow would be a static mesh KActor and the string would be a skeletal mesh KAsset that are tied together via a physics constraint. The arrow would be tied to one end of the string which would be the bone at the end of the string mesh. When the arrow hits the target a dynamic constraint is generated to tie the arrow to the target which is then pulled back to the user of the bow.