Houdini 13.0 Nodes

interface version 2

Generates a spiral (with support for different variants and a backbone).

This SOP can generate an archimedean, logarithmic or arbitrary attribute-driven spiral. The spiral is built either on a (world-axis aligned) linear segment or around an input (“backbone”) curve.

  • Various supported spiral types.

Parameters

Primitive Type

Type of the generated geometry (polygon, NURBS, bezier, or points only).

Origin, Axis, Height

Parameters of the default backbone (if no backbone curve geometry input connected). Origin of the generated backbone.

Number of Points

Number of points along the generated spiral. The following point distribution modes are available:

at Even Angles

the angle along the spiral between generated points is evenly distributed.

at Even Lengths

length of segments along the curve is evenly distibuted.

Mode

Settings on how the spiral shape is generated.

Number of Turns

The start radius and the number of turns is specified.

Start-End Radii

The start and the end radius is specified.

Note

These parameters act as multipliers if the spiral generation is driven by attributes.

Radius %

An overall scale value on radii parameters.

Turns

Number of turns.

Start Radius

The starting radius of the generated spiral.

End Radius

The ending radius of the generated spiral.

Roll

Roll around backbone.

Spiral types
Archimedean
Linear Factor

Linear factor of the calculation.

Exponent

Exponent of the angle.

Logarithmic
Linear Factor

Linear factor of the calculation.

Exponent Factor

Exponent factor of the calculation.

Tip

Using a Linear Factor of 0 results in a regular helix shape.

Attribute

This mode requires a connected backbone curve (with attributes present for twist and radius).

Twist Attribute

Name of the point attribute driving the twist around the backbone. If turned off, a simple linear twist is applied.

Twist Mode

Controls how the twist attribute gets interpreted:

  • Relative: attribute values are interpreted as the relative twist from the previous point.

  • Absolute: attribute values are interpreted as the number of turns at the given point.

The Turn parameter acts as a twist multiplier in both modes.

Radius Attribute

Name of the point attribute controlling the radius of the spiral at the given point. If turned off, a simple linear progression between Start Radius and End Radius is used.

Radius Mode

Controls how the radius attribute gets interpreted:

  • Relative: attribute values gets fitted between Start Radius and End Radius.

  • Absolute: attribute values are only multiplied by End Radius.

Helix

Helix uses radii, turns, and height parameters only (so there are no additional controls).

Initialize Helix Shape

Press this button to get a regular helix-shape quickly.

Release Notes

interface version 2 —

2014-06-21

  • Added “Helix” mode

  • Various minor UI changes

2012-11-16

Added support for other primitive types than polygonal (NURBS, bezier, points-only).

2012-09-14

Initial release of version 2.