Houdini 20.5 Nodes Geometry nodes

Attribute Rename geometry node

Renames or deletes point and primitive attributes.

On this page

The Attribute Rename op allows you to manually rename and delete point and primitive attributes. The RenderMan page remaps attributes especially for the creation of .rib data streams for use with the RenderMan renderer.

Accepts geometry of all types for remapping, renaming, and deletion.

Renderman examples

Cd Cs "vertex color" 0 Map diffuse color as a RIB per vertex color.
uv s "varying float" 0 Map texture coordinates to RIB “s” coordinate as a

single varying float

uv t "varying float" 1 Map texture coordinates for “t” However, the offset is

1, meaning that the second coordinate is used as the “t” coordinate.

Advanced

When generating blobby primitives in RIB, the string parameters were hard-coded to an empty list. SOHO will now search for a detail attribute named “RiBlobby_Strings” (case sensitive). This value of this string will be parsed using the syntax described in the Python function shlex.split(). The resulting list of strings will be output in the RiBlobby() call.

Parameters

Point

Overview

Renaming of point attributes. Specify the existing attribute in the first column. Specify the name of the new attribute in the second column.

Delete Attributes

Specify existing attributes to delete.

Keep Attributes

Specify existing attributes to not delete. Any attributes that match this, and are not deleted by the delete string, will be kept. All others will be deleted.

Update Local Variables

All local variables referring to the renamed and deleted attributes are also renamed or deleted.

Vertex

Overview

Renaming of vertex attributes. Specify the existing attribute in the first column. Specify the name of the new attribute in the second column.

Delete Attributes

Specify existing attributes to delete.

Keep Attributes

Specify existing attributes to not delete. Any attributes that match this, and are not deleted by the delete string, will be kept. All others will be deleted.

Primitive

Overview

Renaming of primitive attributes. Specify the existing attribute in the first column. Specify the name of the new attribute in the second column.

Delete Attributes

Specify existing attributes to delete.

Keep Attributes

Specify existing attributes to not delete. Any attributes that match this, and are not deleted by the delete string, will be kept. All others will be deleted.

Detail

Overview

Renaming of detail attributes. Specify the existing attribute in the first column. Specify the name of the new attribute in the second column.

Delete Attributes

Specify existing attributes to delete.

Keep Attributes

Specify existing attributes to not delete. Any attributes that match this, and are not deleted by the delete string, will be kept. All others will be deleted.

RenderMan

Overview

This tab allows the specification of how attributes will be output to a RIB stream. The first column specifies the name of the Houdini attribute. The second column is what the RIB declaration should be named. The menu of types is the allowable types for RenderMan attribute data. The offset allows you to offset into the Houdini attribute when specifying the RenderMan values.

For Houdini point attributes, either Varying or Vertex types should be used.

For Houdini primitive attributes, either Uniform or Constant types should be used. The Constant type is more efficient when dealing with mesh & NURBS primitives, otherwise there’s really no difference between the two.

Please see the “Application Note #22” from Pixar for a good description on the differences between the different RenderMan types.

Add Default Mappings

Adds the standard attributes, which can be mapped to the RIB standard variables. Turning on the toggle will add attribute mappings for:

Houdini

RIB

Cd

Cs

Alpha

Os

uv(0)

s

uv(1)

t

N

N

rest

Pr

width

width

Update Local Variables

All local variables referring to the renamed and deleted attributes are also renamed or deleted.

Overwrite Existing Attributes

If the specified destination attribute already exists, it is deleted and replaced by the source attribute.

Encode Invalid Attribute Names

If the name provided for any source or destination attributes is invalid (contains any character other than numbers, letters, and underscores, or starts with a number), turning on this option causes the attribute name to be encoded using the same algorithm as the encode function. This encoded attribute name can be decoded back to the original string with the decode function. With this option turned off, invalid attribute names generate a warning, and simply replace all invalid characters with underscores.

Examples

AttributeRename Example for Attribute Rename geometry node

This is an example of how the Attribute SOP is used to delete and rename attributes within Houdini. Attributes may also be renamed for proper RIB outputs for Renderman.

See also

Geometry nodes