Houdini 20.0 Shelf tools

Blend shelf tool

Blends the positions and orientations of the current object transform with target objects.

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This tool will blend the current object transform with other objects.

Using Blend Constraint

  1. Click the Blend tool on the Constraints tab.

  2. Choose the object you want to constrain and press Enter to confirm your selection.

  3. Select one or more targets objects in the desired order. Hold ⇧ Shift to select multiple objects.

  4. Review the Toolbar Parameters. Some of the toolbar parameters match node parameters directly (such as Mask and Weight), while other (such as Mode, Keep Position, and Add Keyframe) affect how the nodes are created.

  5. Press Enter to confirm your selection.

This tool creates a new constraints CHOP Network inside the object, or reuses an existing one.

A Simple Blend node is created based on the selected objects and the blend mode. The constraint is added after the node that has the output flag and the output flag is set to the new node.

Toolbar Parameters


The blend mode.


Creates a Blend node in Proportional mode. This supports multiple targets.


Creates a Blend node in Difference mode. This supports multiple targets.


Creates a Sequence node. This supports multiple targets.

Simple Blend

Creates a Simple Blend node. This supports only a single target.


Select which transform components to blend.


The initial blend weight.

Keep Position

When Keep Position is on, applying the constraint won’t change the current object position.


The constraint will blend the target transforms without keeping an offset.


Targets are pulled using the Constraint Object Offset instead of the Constraint Object. This means that the targets keep their own offset.


An offset node is created after the constraint.

Add Keyframe

Add a transition keyframe to enable the constraint at the current time.

See also

Shelf tools

Using the shelf

  • Customize the shelf

    How to change the look of the shelf, change and rearrange its contents, and create your own shelf tools.