MultiJoints - Collisions

Owned by thomas (Unlicensed)
Last updated: 21 May, 2015
2 min read

Collisions between rigid and soft bodies can be turned on or off selectively, e.g. with global and exclusive, but joints provide an additional method. To give you total control over interacting objects, this panel provides several modes for various occasions and setups. It is actually really important to make up your mind about collisions, because this feature strongly affects simulation speed and your final results. Without collision detection, bodies will interpenetrate, which is normally only useful for certain effects. The options from this panel only affect joined nodes, but not their interaction with other rigid or soft bodies without joints. In other words: even if you have disabled collision for connected objects, they are still able to collide with “regular” items, e.g. joined bricks falling onto a ground.

 

 

 

Enable if break

Under certain circumstances, a connection can break leaving two separated or hinged bodies behind. RealFlow’s standard setting is “No”, but there is one thing to consider: if collisions were enabled at the moment of creation, they will remain active, regardless of whether the joints are broken or not.

In case "Enable if break" is set to "No", the linked nodes can interpenetrate. To achieve a more realistic scenario, it is advisable to set “Enable if break” to “Yes. When this mode is active and any joint, linking a body from “Objects A” with a body from “Objects B”, is broken, you can achieve the following combinations:

  • If “Disable collisions by pairs” is active, it enables only collisions between the A-body and the B-body.
  • If “Disable all collisions A-B” is active, it enables collisions of the A-body with all nodes from “Objects B” and collisions of the B-body with all items, listed under “Objects A”.
  • If neither of the previous modes is active, the action is the same as with “Disable all collisions A-B”.
Enable if distance exceeded

The mode of operation is the same as with “Enable if break”, but is not based on breaking joints, but on a certain distance between two linked points of a joint. Again, you can choose between “Yes” and “No”.

@ Enabling distance

If “Enable if distance exceeded” is active, this parameter becomes accessible. If the distance is greater than the given value, collisions can take place.

@ Enabling distance random

Similar to “@ Max force random”, this parameter adds a random number to “@ Enabling distance” to create a more natural look. The value is calculated between 0 and the number entered here.