Curves

Select an option from the Curves menu to create Bézier curves, composite curves, ellipses, spirals, helices or planar sections.

• Bézier curves — Click to create a Bézier curve. The curves are defined either interactively or by entering coordinates.

  This creates a curve by joining user-specified points.

  

  Bézier curves are parametric cubic curves. The portion of the curve between points is a span. Each span is defined by a start and end point, start and end tangent, and start and end magnitude. On creation, there is tangency continuity between spans.

  Selecting the curve and then a point on the curve displays the point, tangent, and magnitude.

  

  Editing the curve enables you to:

  Move the start/end point:

  

  Change the tangent direction:

  

  Change the tangent magnitude:

  

  For more information, see Creating Bézier curves example and Editing a Bézier curve.

• Composite curve creator — Click to display the Create Composite Curve toolbar. Use to create a composite curve from existing curves and surfaces.
• Ellipse — Click to create an ellipse by specifying its centre, major axis length and minor axis length.
• Spiral — Click to create a spiral by specifying the start radius, end radius and number of turns.
• Helix — Click to create a spiral by specifying the height, pitch, turns, and radius.
• Planar Section — Click to create a curve from a planar section.
• Spun Profile — Click to create a profile curve from a revolved surface.