Houdini 20.0 Nodes VOP nodes

Field Parameter VOP node

Provides a “fallback” value for a field/attribute if the field does not exist or the given field name is an empty string.

Since 12.0

This node may be useful for building low-level assets. For a more useful higher-level version, see the Pyro Field VOP.

Parameters

VOP Parameters

Field Name

The name of a field such as density, or a local global (as on the Global Variables VOP such as P or v, or a VEX expression (not an Hscript expression) such as set(P.x, v.y, Pz).

Field Type

The required type of the incoming field.

Promote

Convert the incoming value from the field to a different data type. See the data type you want to convert to with the Output type parameter.

Output Type

The data type output by this node.

Method

How to fill in the extra components when converting to a data type with more components than the incoming type, for example converting a vector to a vector4. Or, what value to use when converting from

The following options are available when converting “up”.

Repeat last comp

Repeats the last component of the input. For example, converting a float 4.0 to a vector would give 4.0, 4.0, 4.0

Pad with 0s

Fills extra components with 0s. For example, converting a float 4.0 to a vector would give 4.0, 0.0, 0.0

Pad with 0s

Fills extra components with 1s. For example, converting a float 4.0 to a vector would give 4.0, 1.0, 1.0

Pad with constant

Fills extra components with the value of the Padding constant parameter.

The following options are available when converting from a vector to a float.

Component n

Use the value of the given component of the vector.

Min/Max/Average/Sum/Length

Use the given function to combine the components of the vector into a single value.

The following options are available when converting from a vector4 to a vector.

Truncate

Drop the last component of the vector4 to create a vector.

Dehomogonize

Divide the first three components by the fourth (W) component.

Padding Constant

When Method is “Pad with constant”, the constant value to use to fill in the extra components.

Default Value

The constant value to use for lookups into the field if the field does not exist (or the field name is blank).

See also

VOP nodes