For 2D CAM, the pocket operation does not give an intuive way to recognize islands within the pocket. Although two chains can be slected with one enclosed by the other and the resulting tool paths will result in correct geometry, there is not an intelligent transition between them.
Example: With a circular pocket with concentric circular island, two nearly-seperate tool paths are created. One spiral plunges counter-clockwise to mill the contour of the outer edge, then retracts. The second spiral plunges clockwise to mill th einner circle countour.
Expected behavior: One one plunge is needed for this operation. The entire circular pocket should be milled by first spiral plunging in to the outer contour, then spiraling inward until the inner countour is milled.