The Iterator node is a next generation type of thinkingParticles nodes,
it allows to Iterate or "loop" the evaluation of a particle
setup. Similar to a Do or For loop in a programming language, this Node
allows to call several times a network of nodes connected to it.
The use of this Node is endless and can be helpful in nearly every complex
setup of an advanced particle system. Please check out the example presented
at the end of this page, to learn more about the use of an Iterator node.
ON - (Bool) This input data
stream determines whether the operator is considered 'on' or 'off.' You
can connect other operators to this input channel such as a Bool
Helper to activate/deactivate the whole operator.
Time - (Time) This input data stream is used to define the local
time for the operator when the user wants to override the default system
time.
Count - (Integer) sets the number of iterations the Iterator should
run through
On - (Bool) this output
is set active (True) as long as the current Iteration takes place.
Number - (Integer) outputs the loop counter. This number represents
the current position of the Iterator loop.
Number Normalize - (Scalar) outputs the Iterator loop position
in a normalized way (0-1). A value of 1 means that the end of the Iterator
loop has been reached.
Width - represents a fixed value that indicates the number of
steps a loop will go through. This number is calculated by 1/Count, a
good use of this value is to create averaged values by adding up Iteration
loops.
Count - sets the number of loops to go through for this Iterator.
We would like to create a "ray shooter setup" to find an exit
for particles out of a box room with a tiny hole in it. To do this we
need to send several random rays form each particle position to test for
a hole in the box. When a hole is found, the particles need to be sent
in that direction.
The example above uses the Iterator node to loop through the connected
nodes 20 times.
As you can see in the above example the Iterator activates the 3 Random
helper nodes to create a randomized Vector pointing all around in the
scene. With an Iterator node set to 20, a total of 20 different randomized
vectors will be created. All Particles in the new Group will be evaluated
20 times as well and based on the result of the Intersect node, the particles
are moved into a different Group to remove them from all further Iterations.
In the setup as seen above, the Intersect node is used to find a "No
Intersection", this was achieved by using the Invert helper node
connected to the Hit output port. So whenever, the Intersect does not
create a result it will activate the Group switching and it will also
use the vector to accelerate the particles so that they can move outside
the box.