Houdini 20.5 Nodes APEX nodes

rig::SampleSplineTransforms 2.0

Samples a variable number of transforms from a spline.

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Since 20.5

Samples a variable number of transforms from a spline. The point count of the resampled spline geometry matches the number of connected xforms subports.

The resampled curve is output via the outgeo port, and its corresponding transforms are output on the xforms subports (they are also available as the transform point attribute on the outgeo geometry). The name attribute of each point in the output geometry is set to the corresponding transform’s output name (xforms subport name).

By default, the -Z axis of the output transform points toward the next point in the resampled spline. Users can update the tangent vector to support arbitrary output orientations.

Inputs

geo: Geometry

Geometry containing splines. The spline primitive must have a transform point attribute (which will be resampled), and optionally a twist point attribute specifying an additional counterclockwise rotation (in radians) that is applied about the xforms' local tangent axis.

primnum: Int

The primitive number of the spline to sample.

tangent: Vector3

The local space tangent vector of xforms that is aligned to the next point. The default value is the -Z axis (the -Z axis of xforms points toward the next point).

smooth: Bool

If set to True, adds smoothstep smoothing to the output transforms. The default value is False.

Outputs

outgeo: Geometry

Geometry containing the resampled spline. The output geometry has the following point attributes:

  • curveu: The parametric value of the sampled point on the input geometry geo.

  • name: The name of the xforms subport corresponding to the point’s transform.

  • transform: A 3×3 matrix with the resampled transform.

  • tangentu: A vector that points in the direction of the next point.

arclength: Float

The arc length of the input control spline specified by geo and primnum.

xforms: VariadicArg<Matrix4>

The sampled transforms. The number of connections to this port controls the number of resampled points in the outgeo spline.

See also

APEX nodes