What is a Curve Entity?


In Pilot3D, a “curve” entity can be a line, a polyline, a NURB curve, or any combination of these. This is done by assigning a special indicator code to each of the edit points that define the entity. The code tells the program whether a smooth curve passes through each edit point (a ‘c’ point) or whether the point defines a hard or “knuckle” point (a ‘k’ point). Therefore, a polyline would have a ‘k’ indicator for each point and a curve would have a ‘c’ indicator for each point. To avoid confusion, Pilot3D calls any combination of curves and polylines a “curve” entity. When you add or create a new curve you can override the default curve or polyline input by entering each new edit point with the ‘c’ or ‘k’ letters. After creation, you can convert (toggle) any curve edit point back and forth between a ‘c’ and ‘k’ point using the Curve-Knuckle Toggle command. This ability to mix curves and polylines and to convert easily between the two makes designing complex shapes much easier. You do not have to waste a lot of time joining or breaking separate curve and polyline entities, as in most CAD and graphic arts programs.