曲线方法

Synopsis

obj list = BCURVE/CURVE,objlist1[,ENDOF[,objlist2|,numlist]][,DELETE|,BLANK][,IFERR,label:]

Description

Using the curve method converts existing curves (lines, arcs, or conics) to B-splines. The newly created B-spline lies on top of the original curve, unless the minor words BLANK or DELETE are invoked.

Converting lines generates first degree Bezier curves.

Converting arcs and conics generates single segment quadratic splines, with the exception of arcs and ellipses with delta angles greater than 120 degrees. In this case, a multiple segment spline of degree 4 is created.

Parameters

Parameter

Description

CURVE

Minor word that indicates the B-spline is created from existing curves.

entlist1

A list or array of existing curves which are converted to B-splines.

ENDOF

Minor word that indicates the direction of the pole arrays are to be determined by the following optional list or array. The direction of the data base parameters for each curve is the default for the direction of the pole array.

entlist2

Optional list or array of existing points that are used as reference points to indicate the direction of each pole array. The closest endpoint is the start of the pole array.

numlist

Optional list or array of PMODs that indicates the direction of each pole array.

DELETE

Minor word which indicates the original curves are to be deleted after the creation of the B-splines.

BLANK

Minor word which indicates the original curves are to be blanked after the creation of the B-splines.

IFERR,label:

Specifies a label to which program execution jumps if the system cannot create the curve from valid data.

Parameter	Description
CURVE	Minor word that indicates the B-spline is created from existing curves.
entlist1	A list or array of existing curves which are converted to B-splines.
ENDOF	Minor word that indicates the direction of the pole arrays are to be determined by the following optional list or array. The direction of the data base parameters for each curve is the default for the direction of the pole array.
entlist2	Optional list or array of existing points that are used as reference points to indicate the direction of each pole array. The closest endpoint is the start of the pole array.
numlist	Optional list or array of PMODs that indicates the direction of each pole array.
DELETE	Minor word which indicates the original curves are to be deleted after the creation of the B-splines.
BLANK	Minor word which indicates the original curves are to be blanked after the creation of the B-splines.
IFERR,label:	Specifies a label to which program execution jumps if the system cannot create the curve from valid data.