Basic Curves and Profiles Operations
The curve and profile modeling capabilities in nTop allow users to create and manipulate 2D and 3D curves, just like in traditional CAD systems while maintaining the unique advantages of the implicit modeling approach.
Curve Capabilities
The unified curve architecture is built around five key types:
- Abstract Curve type, and four concrete implementations:
- Arc
- Line
- Spline
- Polycurve
The genius of this system lies in its interoperability – any curve type can be used in any “Curve” input, thanks to automatic type conversion to the abstract Curve type. This unified approach allows engineers to create complex curve networks by combining different curve types seamlessly, without worrying about type compatibility issues.
A design might start with imported spline curves from a CAD system, incorporate precise arc segments for specific geometric requirements, and connect everything with straight line segments – all within a single, cohesive workflow.
Profile Capabilities
The Profile type represents sets of coplanar curves that can be:
- open or closed
- simple or complex with multiple loops.
This flexibility enables the creation of sophisticated 2D shapes that serve as the foundation for 3D geometry generation through extrusion, revolution, or sweeping operations.
The Profile system includes two important field properties that extend its utility beyond simple 2D shape definition:
- The first is a signed distance field to the infinite extrusion relative to the profile’s plane, which enables advanced geometric operations and field-driven modifications.
- The second is an unsigned distance field to the enclosed region, which is particularly useful for creating complex internal structures or for defining regions for lattice filling.
Open profiles receive special treatment in the new system. When an open profile is used in operations that require closure, nTop automatically extends the profile and closes it with straight lines if the infinite extensions intersect.
This intelligent behavior reduces the manual work required to prepare profiles for 3D operations while maintaining predictable and controllable results.
Now in the next few lessons we will explore these modeling capabilities with several follow-along examples.