Houdini 16.5 Nodes VOP nodes

Add Attribute VOP node

Adds a new attribute.

This operator adds a new attribute. The type of the attribute will be set from the value passed in. The value will be used as the default value for the attribute.

If the attribute already exists, it will attempt to be converted to the type.


This does not change the attribute values. To change the value of the currently processed element, see the Bind Export VOP. To change other elements or other attribute classes, see Set Attribute VOP.


All geometry creation is done after all the elements have been processed. Therefore, you cannot read from geometry you just created.

Adding a value to the local variable will also update the varmap attribute which is used by SOPs such as the Point SOP to determine mapping of attribute values to local variables available in the SOP.



The type of attribute that this VOP will create. Choose between Vector (XYZ), Float (scalar), Vector4 (XYZW), Integer (scalar), Matrix3 (3×3 matrix), or Matrix (4×4 matrix). This also controls the type of the input Default Value.

Geometry Handle

Refers to what geometry to write to. The default of 0 means the currently processed geometry.

Attribute Class

What type of attribute to create.


The name of the attribute to create. The default Cd will create an attribute named Cd, otherwise known as Diffuse Color.

Local Variable Name

If specified, this will create a local variable ($NAME) on the SOP which can be used to evaluate the attribute in an expression.

Type Info

Refines the generic attribute to have more semantic meaning. This is a hint to some SOPs. For example, position vectors are translated, while Normal vectors are not.

See also

VOP nodes