curvearclen

Since	18.5

float  curvearclen(vector positions[], float uv1, float uv2, int closedflag, int fmt, int order)

float  curvearclen(vector positions[], float uv1, float uv2, int closedflag, int fmt, int order, int divs)

float  curvearclen(vector positions[], float uv1, float uv2, int closedflag, int fmt, int order, int divs, int primuvmode)

float  curvearclen(vector positions[], float uv1, float uv2, int closedflag, int fmt, int order, int divs, int primuvmode, float primuvtol)

Returns the arc length between two parametric UV coordinates on a given primitive. This lets you measure the distance across a polygon face or along a curve.

geometry

A string specifying a geometry file (for example, a .bgeo) to read from. When running inside Houdini, this can be an op:/path/to/sop reference.

points

The array of control points to define the curve.

uv1

The start coordinate in the primitive’s parametric space to measure between.

uv2

The end coordinate in the primitive’s parametric space to measure between.

closedflag

The curve can be closed or open. In a closed curve, the last control point will be connected to the first one.

fmt

The curve type to create. You can used constants defined in math.h, or 0 to create a polygon curve, 1 to create a bezier curve or 2 to create a NURBS curve.

order

The curve order for NURBS or Bezier curves. This is ignored for polygon curves.

divs

The number of divisions per segment to use or 10 if not supplied.

primuvmode

Define the uv1 and uv2 coordinates units. See primuvconvert for the list of modes.

primuvtol

A tolerance used when computing the curve length to do uv coordinates conversions.