Houdini 20.5 Nodes Geometry nodes

Twist geometry node

Applies deformations such as bend, linear taper, shear, squash/stretch, taper, and twist.

This node type is deprecated. It is scheduled to be deleted in an upcoming revision of Houdini.

Use the Bend node instead.

(Since version 17.0.)

On this page

You can twist any geometry.

Using Bend

  1. Select the points to bend.

  2. Click the Bend tool on the Deform tab.

  3. Orient the capture planes to encompass the region you wish to taper.

  4. Use the Bend to control the amount of bending.

Using Linear Taper

  1. Select the points to taper.

  2. Click the Linear Taper tool on the Deform tab.

  3. Orient the capture planes to encompass the region you wish to taper.

  4. Use the Taper parameter to control the amount of tapering.

Using Squash and Stretch

  1. Select the points to squash and stretch.

  2. Click the Squash and Stretch tool on the Deform tab.

  3. Choose an axis as the Primary Axis in the drop-down menu on the parameter editor.

  4. Use the Strength and Rolloff parameters to control the amount of squashing and stretching.

You can change the Operation of the deformation in the drop-down menu on the operation controls toolbar or the parameter editor, since twist, bend, taper, linear taper, and squash and stretch all put down the same node.

Using Taper

  1. Select the points to taper.

  2. Click the Taper tool on the Deform tab.

  3. Choose a Primary Axis and Secondary Axis in the drop-down menus on the parameter editor.

  4. Use the Strength and Rolloff parameters to control the amount of tapering.

Using Twist

  1. Select the points to twist.

  2. Click the Twist tool on the Deform tab.

  3. Orient the capture planes to encompass the region you wish to taper.

  4. Use the Twist parameters to control the amount of twisting.

Parameters

Group

Subset of geometry to deform.

Operation

Type of deformation.

Bend

Bends the geometry.

Note

Rolloff acts as a bias for this operation.

Linear taper

Linearly scales the geometry along its length.

Shear

Moves the points on one side of the geometry up and the other side down.

Squash and Stretch

Scales up or down in one direction, while doing the opposite in the other two directions, to deform the geometry while retaining the same volume.

Taper

Scales the geometry along its length.

Twist

Twists the geometry around the axis.

Primary Axis

Deformations occur about the primary axis.

Secondary Axis

Points along the secondary axis remain unchanged.

Pivot

Local origin of deformation.

Strength

Strength of the deformation.

Rolloff

Attenuation of deformation.

Note

This parameter normally represents an exponent, but when Operation is Bend, points along the Secondary Axis scale the bend from Rolloff - 0.5 to Rolloff + 0.5, so you will usually want to keep Rolloff between -0.5 and 0.5.

Inputs

Twist Source

Can be any geometry, including NURBS and Beziers, but should have sufficient points for a better deformation. Use the Divide SOP or Refine SOP to achieve this.

Locals

CEX, CEY, CEZ

The centroid of the input

XMIN, XMAX

The X extents of the bounding box of the input

YMIN, YMAX

The Y extents of the bounding box of the input

ZMIN, ZMAX

The Z extents of the bounding box of the input

SIZEX, SIZEY, SIZEZ

The size of the bounding box of the input

Examples

BasicTwist

This example shows off the flexibility of the Twist SOP. The Twist SOP has many operations such as twist, bend, shear, taper, linear taper, and squash.

Contained are examples of how each Operation affects different geometry types: Polygon, Mesh, NURBs, NURBs Perfect, Bezier, and Bezier Perfect.

Geometry nodes