MultiJoints - Break

From the moment a link is broken, the connection stops working and you cannot observe the typical pull-back behaviour. With "Break" parameters you can define rules and criteria for breaking joints under certain conditions. These settings give you extra realism, especially with any form of collapsing structure, but also in situations where the connections act like ropes or hinges which are broken due to high forces.

Break if max force reached

As you may remember, “@ Max force” defines the rigidity of a connection between two bodies. Low values create less restricted motion and pull-back forces are not that strong. When this given “@ Max force” value is reached, the joint breaks – but only if this mode is active.

Break all in pair if few unbroken

This is an interesting feature, because it reacts to the number of broken connections. It is best explained with a simple example: two cubes are linked via 5 connections – 4 at the cube’s vertices and one in the geometric centre of the polygons. Now imagine that 3 of these connections are already broken, but the remaining 2 are strong enough to keep everything together.

In a case like this, the MultiJoint would act like a hinge and the bodies would be loosely connected. With “Break all if few unbroken” set to “Yes” and “@ Unbroken number to break all” set to 2, RealFlow would break the remaining links and the objects would be completely separated. To give another illustration: imagine a brick wall being destroyed by a hitting object. Some bricks might stick together, because not all joints are broken and so the nodes are hinged. To avoid such a behaviour, just define a certain limit with “@ Unbroken number to break all”, e.g. 2, to dissolve all connections.

This feature has two settings: “Yes” to enable it and “No” to deactivate it. It is also important to know that it can be used with any break mode.

@ Unbroken number to break all

By default this parameter is locked and only accessible when “Break all in pair if few unbroken” is set to “Yes”. If this value is reached by a particular pair of joined bodies, all remaining connections between them will be broken. Other links in the MultiJoint will not be affected. You can find an example under “Break all in pair if few unbroken”.

Break if distance is exceeded

Again you can choose between “Yes” and “No” to activate/deactivate this function. Like many other similar parameters, this one also depends on the distance between points, linked by an individual joint. A very important factor with distance is “@ Max force”, because it directly affects how far bodies can separate from each other before they are pulled back. By activating “Break if distance is exceeded”, you will unlock the parameter below where you can enter the desired distance value. If “Force max mode” is set to “Unlimited’” this feature is not available, because the linked points cannot separate so it makes no sense to talk about distance.

@ Break distance

If the given distance is exceeded, the connection is broken. “@ Break distance” is measured in RealFlow units, related to the viewport’s grid.

@ Break distance random

Here it is possible to add a random number to the previously defined “@ Break distance” parameter. The final value is calculated between 0 and the entered setting.