By itself, Rhino is a very powerful surface modeling system, and can be used to design and fair hullforms. However, with the addition of a few new tools, it can be even more productive. Orca3D enhances and leverages Rhino's capabilities.
There are two basic approaches to modeling hulls in Rhino:
| 1. | Draw a series of curves (stations), and loft a surface through them. This approach has the advantage of creating a shape very quickly, and being assured that the surface passes through the desired station shapes. However, usually the surface that is created is greatly overdefined, and subject to unfairnesses which can be very difficult to remove. This approach is more useful for other surfaces found in marine vessels, such as portions of the superstructure. |
| 2. | Create a surface with a relatively low number of control points, and move those control points to "stretch" and "sculpt" the surface into the desired shape. Sections can be computed on the surface, to give the designer a better idea of the actual shape. This approach has the advantage of producing fair surfaces, but it can be more difficult to guarantee that the surface passes through a given point or points in space. In general, fairness is more important than passing exactly through a given point, so this approach is more effective (an exception to this might be trying to match the offsets of an existing hull for stability calculations, where fairness is not as important as matching the offsets exactly). |
Orca3D is primarily focused on the second approach, known as "direct surface manipulation." Tools are provided to:
| • | Define stations, buttocks, waterlines, and other curves on the surface (Sections) |
| • | Easily move control points to exact locations (OrcaMove) |
| • | Handle the transition of the surface as it wraps from the stem around the forefoot to the bottom, with slope and curvature continuity (Corner Continuity) |
Note that the Orca3D tools can be used on any type of surface, no matter how it was generated.
