Nodes - MultiJoints

MultiJoints are a sophisticated way of connecting objects. With these links it is not only possible to tie objects together, but they are fully customizable and controllable by the user. You can define forces or distances when the connections break, enable or disable connections, achieve plasticity and deformation effects and even mimic constraints like ropes or hinges. One of the most common applications for MultiJoints is to connect construction elements or pieces from prefractured objects to achieve a realistic dynamic behaviour, for example at impacts or with collapsing structures. MultiJoints can prevent the individual elements from separating completely, because it is possible to define forces which keep the pieces together. When a certain distance or force is reached, the connection can be released and from that moment the fragments move freely.

But, MultiJoints cannot be used with rigid bodies alone, it is no problem to connect soft bodies with rigid bodies, or just different soft bodies. With this feature it is possible to simulate plants or car crashes where a deformable car body is connected with rigid glass panels, for example. Another idea is to create soft structures inside breaking rigid bodies to simulate complex deformations, for example a wireframe. Furthermore, you can use more than one MultiJoint node per object and literally create different layers of connections. This opens a world of infinite possibilities and results.

MultiJoints are not nodes in a physical sense, they are a method to connect rigid and soft bodies and cannot work with objects without activated dynamics. The MultiJoint feature is located under: 

Edit > Add > Objects > MultiJoint

Anti-Parallel Surfaces

“Anti-parallel” is a term you will come across quite often in the following descriptions. From a user's perspective, these faces and polygons appear as parallel, but there is one difference: the normal's of the polygons have opposite directions as shown in the image below: