Cubic Bézier
A cubic Bézier curve is a curve object in 2D or 3D having a single edge defined by a rational function of degree 3. The edge must not intersect itself. To create a cubic Bézier curve, you can:
•
Right-click the 2D or 3D Geometry node and add a Cubic Bézier node () (in 3D from the More Primitives submenu) to the sequence, then define it in the Settings window, or
•
Select Cubic Bézier from the More Primitives menu on the Geometry toolbar Primitives group to add a Cubic Bézier node ()the sequence, then define it in the Settings window, or
•
On the 2D Sketch toolbar Draw group, select Cubic. Then draw the cubic curve segments of a Bézier curve in the Graphics window. Also see Drawing Geometric Primitives in the Graphics Window.
If desired, enter the properties of the cubic Bézier curve using the following sections:
Control Points
Specify the coordinates for the four control points. The first and fourth control points are the endpoints of the Bézier curve. The second and third control points determine the tangent directions at the endpoints.
Weights
Specify the weights for each control point. The weights are used in the denominator of the rational function. The default is that all weights are 1, which means that the function is a polynomial.
Coordinate System
This section is only available in 3D geometries.
The coordinate system in which the Bézier curve coordinates above are interpreted. From the Work plane list, select xy-plane (the default, for a standard global Cartesian coordinate system) or select any work plane defined above this node in the geometry sequence. If you choose a work plane, the work plane and its coordinate system appear in the Graphics window, using an extra coordinate triad with the directions xw, yw, and zw (which are then used to specify the curve’s position).
Selections of Resulting Entities
This section is not available if the Cubic Bézier node is a subnode under a Composite Curve node.
Select the Resulting objects selection check box to create predefined selections (for all levels — objects, domains, boundaries, edges, and points — that are applicable) in subsequent nodes in the geometry sequence. To also make all or one of the types of resulting entities (domains, boundaries, edges, and points) that the cone consists of available as selections in all applicable selection lists (in physics and materials settings, for example), choose an option from the Show in physics (Show in instances if in a geometry part) list: All levels, Domain selection, Boundary selection, Edge selection, or Point selection. The default is Domain selection, which is suitable for use with materials and physics defined in domains. For use with a boundary condition, for example, choose Boundary selection. These selections do not appear as separate selection nodes in the model tree. Select Off to not make any selection available outside of the geometry sequence. From the Color list, choose a color for highlighting the resulting objects selection. See Selection Colors.
Cumulative Selection
If you want to make the resulting entities contribute to a cumulative selection, select a cumulative selection from the Contribute to list (the default, None, gives no contribution), or click the New button to create a new cumulative selection (see Cumulative Selections).