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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.
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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”.
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