Manual calculation definition of shrinkage compensation

The manual shrinkage algorithm works by stretching features on plates, after splitting the panel into plates. The stretching is applied to the outer geometry of the plates, connection weld lines and mould lines of connected parts (which is later converted into markings). Holes and labels are generally not stretched, but their positions are moved to be consistent with the stretching of the other features. The Compensation of holes (distortion) option in the Compensation Configuration window causes the geometry of the holes to be stretched the same as the other features.

The stretching is performed on a geometry, segment by segment, the application moves the start and end point of each segment away from the center point of the plate. The points move by a distance both along and perpendicular to the main shrinkage direction. This distance equals the projection of the center point in the specified direction, multiplied by that direction’s scale factor.

For segments that are circular arcs, stretching results in an elliptical arc. However, as elliptical arcs are not supported, the stretched curvature is approximated by splitting the segment into 8 smaller segments before moving the start and end points. The new radius of the circular segment is found by translating the center point of the circle and calculating the average distance between this and the updated start and end points of the segment.