instances.cull (procNode)

Keeps the instances a test says to. An instance survives when the value it is judged by is strictly above threshold; invert keeps the rest instead. The value is the mask field when it is wired, else the named point attribute (field.attribute). elements.keep on the points carries every attribute onto the instances that stay, so a culled set realizes as the whole one would have. With nothing to judge by, every instance stays, and inverted, none does.

Inputs

• instances (Points): the set to thin out, points carrying a Mesh.
• mask (Field): the value each instance is judged by. Wired, it outranks attribute.
• threshold (Float, default 0.5): an instance survives when its value reads strictly above this. Raising it thins the set, lowering it fills it back in.
• attribute (String): a point attribute on the set to judge by, read while mask is unwired. A name the points do not carry is refused.
• invert (Bool, default false): true keeps the complement, every instance the test dropped.

Outputs

• instances: the surviving instances.

Which graph calls it

This node is built with proc.graph and g:node, and a proc.graph graph calls it as g:node("<id>", "instances.cull", ...). A graph built with proc.define calls g.instances.cull in its place, the node written in the call form; g.op.instances.cull there is refused, naming it.