Houdini 20.0 Nodes Geometry nodes

Pack Inject geometry node

Replaces the contents of Packed Primitives in-place.

Since 19.0

The contents of the selected packed primitives will be replaced by the geometry on the second input.


In replace mode, this will change the selected packed primitive types to Packed Geometry.

In collation mode, the selected packed primitives will either become Packed Geometry or the source primitive type.


No transformations are applied to the injected geometry - they are sourced from the local space in the source, and applied to the local space of the destination, with no transformation applied.



The packed primitives to inject new geometry into.


How to select geometry in the second source input to inject into the selected packed primitives.

Pack Source and Replace

The raw geometry of the second input is used to replace the contents of the packed primitive. This is equivalent to packing the second input and replacing the selected primitives with that; but copying all the transform and metadata on the primitives.

Collate Packed Sources

For each selected packed primitive a source primitive in the second input is found. The source primitive must be itself a packed primitive. The untransformed geometry of the source primitive is then injected into the destination primitive without transformation.

This is useful for updating a bunch of packed primitives from a library of instances. The resulting packed primitives will properly instance when the same source primitive is referenced.

Collate by

How to choose a matching primitive from the second source input for each selected packed primitive.

Single Source

A single packed primitive is used to replace all of the target primitives.

Primitive Number

The raw primitive number is used. Primitive 5 in the target will match with primitive 5 in the source. Note this is the absolute primitive number, not the position in the selected group.

Collation Attribute

An attribute is used to match. The attribute must exist on both the the target and the source. Both attributes must be the same class (either point or primitive) and same type (either integer or string).

Attribute Pair

A pair of attributes is used to match. Like with collation attribute, the attributes must be the same class and type, but the source and target may use different named attributes. This is useful when a source library is using a name that already has meaning on the target, so the target attribute needs to pick something non-conflicting.

Source Primitive

Which source primitive to use for injection in Single Source mode.

Match Attrib

The primitive or point attribute on the use to pair up primitives for collation. Must be a string or integer attribute. If either attribute is missing, an error will occur.

Source Attrib

The primitive attribute on the second source input to use to pair primitives. The first primitive whose target attribute matches the source attribute of the primitive to inject will be used as a collation pair.

In case of point attributes, it is undefined which primitive will be selected if more than one primitive is attached to a point.

Ignore Missing Sources

If no second primitive is found for collation, no action will be performed and the primitive will be unchanged. If not ignoring missing sources, instead an empty geometry will be injected.

Preserve Second Input’s Packed Type

In collation mode, keep the second input’s pack type rather than hardening into a geometry packed primitive. This is useful if replacing agents-with-agents or similar operations.

See also

Geometry nodes