Automatic Fairing

Surface provides the ability to automatically fair splined patches.

When a surface patch has been created to represent say a part of a ships hull, it may satisfy most of the necessary requirements, such as specified order of continuity with adjacent patches (up to four adjacent patches), passing through numerous surface curves, passing through surface positions All these requirements can place conflicting demands on the mathematical representation of a spline surface. These conflicting demands may result in surface patches which are not fair. The surface can be altered by hand to improve it by moving the control points (sometimes referred to as weights or polygon points). This is not an easy task, if it can be done at all. What is described below is how to use the automatic fairing features of Surface.

The concept of fairness is somewhat subjective, but in recent years various mathematical measures of fairness have been created. The one used in the AVEVA Marine applications is based on an approximation to the thin plate energy in a surface and it is the reduction of this energy which is at the heart of the fairing approach.