NURBS Through Positions
Use this feature to create a generic rational B-spline curve by through positions. The end slopes can be controlled by nodal (point) position, chosen from the Position Menu.
NOTE: When creating NURBS Curves, you will notice that two buttons are added to the Universal Position Menu when creating in both Through or Control modes: OPTIONS and CLOSE.
When using this function, keep the following things in mind:
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The direction for selecting nodes along the curve will be in the same direction by which the resulting spline is defined.
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Curves have a maximum degree of 8, and the default degree for each method of creation (Through or Control Points) is 3. Degree controls the smoothness of the curve being created.
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The multiplicity of internal knots must not exceed the degree.
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Selecting the DONE option button while placing nodes will finish the current NURBS curve and return you to the initial prompt, from where you can select the first point of a new curve.
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Selecting the BACKUP option button will remove the most recently added node from the curve.
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Selecting the Cancel/ESC option button will exit the current function without adding the curve to the database.
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Control Points can be modified through the Edit dialog that appears when a NURBS spline is selecting using the Generic Edit function.
Using the Function:
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Select NURBS Through Positions from theCreate>Spline submenu.
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Indicate a start position (placement for the first node in the curve) using an option in the Position Menu.
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An active node (or node last placed) created via the Through Points command will appear as a rectangle.
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Indicate at least one (1) additional node (point) to generate a curve. The new input will be appended to the active node.
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Select OPTIONS to make modifications to the new curve, or DONE to complete it.
Above > Example of a spline created using NURBS Curve by Through Point