Through Curves

Synopsis

obj = BSURF/CURVE,objlist1[,ENDOF,{,objlist2|,numlist}][,DEGREE,num[,CLOSED]][,IFERR,label:]

Description

Creates a B-surface from a series of existing curves using the minor word CURVE. Open and closed curves cannot be mixed. The surface size is limited by the patch type (single or multiple), as in the Through Points method described on page .

Parameters

Parameter

Description

CURVE

Minor word that indicates the B-surface is to be created from existing curves.

objlist1

A list or array of existing curves which are used as rows to create the surface. The surface passes through these curves.

ENDOF

Minor word indicating that the direction of the row pole arrays is 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 representing each row.

objlist2

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

numlist

An optional list or array of PMODS that indicates the direction of each row pole array. Use the numerical equivalent (1-6) for each desired PMOD.

DEGREE

Minor word indicating that the degree of the surface is to be specified for the V direction. The degree of the U direction determined by the degree of the curves.

num

A positive numerical value or variable which represents the degree of the surface in the V direction.

CLOSED

Minor word that indicates the surface is to be in the V direction. If all the curves are closed, the U direction is also closed.

IFERR,label:

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

Parameter	Description
CURVE	Minor word that indicates the B-surface is to be created from existing curves.
objlist1	A list or array of existing curves which are used as rows to create the surface. The surface passes through these curves.
ENDOF	Minor word indicating that the direction of the row pole arrays is 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 representing each row.
objlist2	An optional list or array of existing points that is used as reference points to indicate the direction of each row pole array. The closest endpoint is the start of the row pole array.
numlist	An optional list or array of PMODS that indicates the direction of each row pole array. Use the numerical equivalent (1-6) for each desired PMOD.
DEGREE	Minor word indicating that the degree of the surface is to be specified for the V direction. The degree of the U direction determined by the degree of the curves.
num	A positive numerical value or variable which represents the degree of the surface in the V direction.
CLOSED	Minor word that indicates the surface is to be in the V direction. If all the curves are closed, the U direction is also closed.
IFERR,label:	Specifies a label to which program execution jumps if the system cannot create the surface from valid data.