B-spline and periodic B-spline¶
The feature creates a free form spline curve in the current Sketch.
To add a new B-spline to the Sketch:
select in the Main Menu Sketch - > B-spline item or
click B-spline button in the Sketch toolbar.
To add a periodic B-spline to the Sketch:
select in the Main Menu Sketch - > Periodic B-spline item or
click Periodic B-spline button in the Sketch toolbar.
Creation of B-spline curve¶
Click in the view to specify the control polygon of B-spline curve. The curve will be shown after the second point is initialized. To stop adding new poles, click Esc button or Apply the operation.
TUI Command:
-
Sketch_1.
addSpline
(degree, poles, weights, knots, multiplicities, periodic)¶ - Parameters
integer – degree of B-spline.
array – list of poles [(x1, y1), (x2, y2), …].
array – list of weights for corresponding poles.
array – parametric knots of B-spline curve.
array – multiplicity of each knot.
boolean – True mentions that the B-spline curve is periodic.
- Returns
Result object.
Each parameter is optional.
Result¶
Created B-spline curve appears in the view.
See Also a sample TUI Script of Create Sketch B-spline operation.
Modification of B-spline curve¶
The following options are provided to modify the already created B-spline curve:
Change weight of each pole.
Add new pole.
The new pole is added after the current by pressing on the corresponding button. The default weight for the new pole is 1.
Note: adding the new pole after the last for non-periodic B-spline will not change the last point of the curve to avoid modification of full sketch.