CoCreate OneSpace Designer - Commands Reference Manual

AM_BSPLINE_INT creates a B-spline using a sequence of interpolation points, through which the curve will pass.

Syntax

                         +--------------------<-------------------+
                         |                                        |
                         |                                        |
---->(AM_BSPLINE_INT)----+---|interpolation pnt|------------------+---->
                         |                                        |
                         +---(:CLOSED)----------------------------+
                         |                                        |
                         +---(:OPEN)------------------------------+
                         |                                        |
                         +---(:BACK)------------------------------+
                         |                                        |
                         +---(:ORDER)---|number|------------------+
                         |                                        |
                         +---(:TANGENT)---+---(:ON)-----+---------+
                         |                |             |         |
                         |                +---|angle|---+         |
                         |                |             |         |
                         |                +---|pnt|-----+         |
                         |                |             |         |
                         |                +---(:OFF)----+         |
                         |                                        |
                         |                                        |
                         +---(:CLEAR_TANGENT)---------------------+
                         |                                        |
                         +---(:APPEND)--|elem|--+-----------------+
                                               (*)                |
                                                +--|select elem|--+

                                       (*) if elem is ambiguous

Options

• :CLOSED closes the B-spline creating tangency and curvature continuity at the first interpolation point. :CLOSED mutually excludes :APPEND.
• :OPEN does not close the B-spline.
• :BACK deletes the last interpolation point specified.
• :ORDER affects the control over the ultimate shape of the B-spline. The default B-spline order of 4 creates a curvature continuous curve that follows its control polygon as closely as possible. The order value can be between 3 and 10; however, a higher order decreases the performance.
• :TANGENT defines a tangent angle at a specified interpolation point.
• :CLEAR_TANGENT removes a defined tangent angle.
• :APPEND appends a B-spline to another element. Either end of the B-spline can be aligned with any type of open element, including another B-spline. The new B-spline has tangent continuity at the intersection point. Note that :APPEND mutually excludes :CLOSED.

When to use

The AM_BSPLINE_INT command automatically computes a series of control points for the curve. There is no difference between these points and user-created control points.

See also