edge:bs
List of: Scheme Extensions
Subjects: Model Geometry
Contents: Kernel

Action: Returns the B-spline approximation information (number of control points) for an edge.

Filename: kern/kern_scm/qedg_scm.cxx

Syntax: (edge:bs in-edge [extra-info=#f])

Arg Types: in-edge edge

extra-info boolean

Returns: real

Errors: -1 (when no B-spline to evaluate)


in-edge specifies an edge.


extra-info is an optional argument that specifies whether or not extra information is required. If extra-info is #t, additional control point information is returned.

Example: ; edge:bs

; Create topology to illustrate command.

(define spline (edge:spline (list


(position 0 0 0) (position 3 10 0)


(position 8 0 0) (position 10 5 0)))))

;; spline

; Get the number of control points.

(edge:bs spline)

;; 6

; Obtain additional information for this B-spline.

(edge:bs spline #t)

; ACIS bs3_curve form open

; open B-spline of degree 3

; 6 control points:

; (0, 0, 0), 0

; (0.82927811664237, 5.6047496784132, 0), 10.4

; 40306508911

; (2.546615525166, 17.211526819864, 0), 21.620

; 646396409

; (7.4352298011772, -4.7927993036719, 0), 27.0

; 05811203544

; (9.3707841024177, 2.5975293979431, 0), 27.00

; 5811203544

; (10, 5, 0), 27.005811203544

;; 6
PDF/KERN/12SCA.PDF
HTM/DATA/KERN/KERN/12SCA/0056.HTM