AutoLISP Developer's Guide > Appendixes > AutoLISP Function Synopsis > Visual LISP Extensions to AutoLISP > 
Curve Measurement Functions
 
 
 

The following table provides summary descriptions of the AutoLISP curve measurement functions.

Curve measurement functions

Function

Description

( vlax-curve-getArea curve-obj)

Returns the area inside the curve

( vlax-curve-getDistAtParam

curve-objparam)

Returns the length of the curve's segment from the curve's beginning to the specified point

( vlax-curve-getDistAtPoint

curve-objpoint)

Returns the length of the curve's segment between the curve's start point and the specified point

( vlax-curve-getEndParam

curve-obj)

Returns the parameter of the endpoint of the curve

( vlax-curve-getEndPoint

curve-obj)

Returns the endpoint (in WCS coordinates) of the curve

( vlax-curve-getParamAtPoint

curve-objparam)

Returns the distance along the curve from the beginning of the curve to the location of the specified parameter

( vlax-curve-getParamAtPoint

curve-objpoint)

Returns the parameter of the curve at the point

( vlax-curve-getPointAtDist

curve-objdist)

Returns the point (in WCS coordinates) along a curve at the distance specified by the user

( vlax-curve-getPointAtParam

curve-objparam)

Determines the point on the curve that corresponds to the param parameter and returns the point

( vlax-curve-getStartParam

curve-obj)

Returns the start parameter on the curve

( vlax-curve-getStartPoint

curve-obj)

Returns the start point (in WCS coordinates) of the curve

( vlax-curve-isClosed

curve-obj)

Determines if the specified curve is closed (i.e., start point is same as endpoint)

( vlax-curve-isPeriodic curve-obj)

Determines if the specified curve has an infinite range in both directions and there is a period value dT, such that there is a point on curve at (u + dT) = point on curve (u), for any parameter u

( vlax-curve-isPlanarcurve-obj)

Determines if there is a plane that contains the curve

( vlax-curve-getClosestPointTo

curve-obj givenPnt [extend])

Returns the point (in WCS coordinates) on a curve that is nearest to the specified point

( vlax-curve-getClosestPointToProjectioncurve-obj givenPnt normal [extend])

Returns the point (in WCS coordinates) on a curve that is nearest to the specified point

( vlax-curve-getFirstDeriv

curve-obj param)

Returns the first derivative (in WCS coordinates) of a curve at the specified location

( vlax-curve-getSecondDerivcurve-obj param)

Returns the second derivative (in WCS coordinates) of a curve at the specified location