MultiJoints - Creation

Owned by thomas (Unlicensed)
Last updated: 16 Jul, 2015
3 min read

This is the place where you specify the objects to be linked. MultiJoints can only be applied to objects with active rigid or soft body features.

 

 

Objects A

Here, the first group of objects is specified you want to connect to a second group, found under “Objects B”. If the node selection list is empty, please check that the objects → “Dynamics” is set to either “Active | Passive rigid body” or “Soft body”.

Objects B

This is the second group of objects you have to choose to create the links:

  • It is possible to leave “Objects B” empty. If you do so, nodes from “Objects A” will be linked with RealFlow’s world space.
  • If you attach exactly the same nodes to “Objects A” and “Objects B” connections between all selected items will be created. A good example is a brick wall. 
Creation Mode

These options determine how the objects are linked together:

  • “By contact”. The nodes from “Objects A | B” are connected automatically. Adjustments are made with the associated “@ Contact ...” parameters.
  • “By stem (leaves A, trees B)”. This mode is suitable for plants and similar setups. The leaves have to be under “Objects A”, the stems or branches under “Objects B”. The leaves have to be very close to the tree's branches.
  • “At locators positions”. Here you create one or more objects and place it between the objects meant to be linked. The joints will be created at the pivot points of the helper nodes. All locator nodes have to be added to “@ Locators”.
  • “At locators bbox centres”. This mode allows you to use any objects shape as a locator. The geometrical centre of a bounding box around the selected locator(s) is used to create the joints.
  • “At locators vertices”. With this mode, the locator's vertex positions are used to connect the two nearest objects from “Objects A | B”. Objects will be linked, even if they are far away from the joint.
@ Contact distance search

This feature works only with “Creation Mode” set to “By contact”. With this parameter you can define the distance at which RealFlow should look for objects to connect. By increasing this value you can look for object pairs which are further away.

@ Contact area min.

This feature works only with “Creation Mode” set to “By contact”. To establish joints, the contact area between the faces of two objects must be greater than this value. It is safe to leave the default value in most cases. The value is measured in metres.

@ Contact angle max.

This feature works only with “Creation Mode” set to “By contact”. Joints will only be created when the angles between nodes' faces are smaller than this value. The value is given in degrees.

@ Contact number max.

This feature works only with “Creation Mode” set to “By contact”. With this parameter you can limit the number of connections. RealFlow selects the most significant joints. Higher settings create more connections.

@ Locators

Here, a node browser is opened where you can choose the objects serving as locators (see “Creation Mode”). Objects, used as locators, do not need dynamic features activated.

Limit processed joints

This option restricts the number of joints that are actually processed during simulation. The number of joints does not change, but RealFlow will choose the ones which are best suited.

@ Max processed joints per pair

By default, all joints are processed at the same time and this can be a time-consuming task. With this parameter it is possible to “group” the joints to accelerate the simulation. An example: a bone linked to its surrounding flesh. The bone’s vertices are used to create the joints, let’s say 1,000 and “Max processed joints per pair” is set to 50. During calculation all of them will be processed, but only 50 at once.

Disable collisions by pairs

When enabled, the solver stops processing collisions between all body pairs connected by joints. This results in shorter simulation times.

Disable all collisions A-B

The difference to “Disable collisions by pairs” is that nodes from “Objects A | B” do not necessarily have to be joined, for example when the distances between them are too big. If you disable collisions between pieces when you already know that they will not interact you will see an increase in simulation speed. An example is a pre-fractured object where you do not need collision between the fragments until it begins to break apart.

Create/Recreate (*)

The asterisk (*) is a marker and can can only be seen when it is necessary to create or update the joints. Alternatively, reset the scene.