Abstract: Techniques for forming a complex shelled object are described. The shelling procedure does not merely combine two shelled objects into in single shelled object, but also integrates the two object with one another without destroying the integrity of either of the shelled objects.

Abstract: The invention includes computer instructions that operate to receive an input corresponding to generation of a pattern in a computer aided design (CAD) solid model. Pattern is comprised of a number of features included within a boundary of the solid model. The instructions further operate to receive an indication of modification to the solid model. The instructions operate to automatically modify the solid model and its boundary based at least upon the received indication. The instructions further operate to automatically determine whether modification, if any, to at least one of pattern and number of features to be continuously included within the boundary of the modified solid model, is necessary, based at least upon the modified solid model and received input. Upon so determining, the instructions operate to cause the necessary modification to be effectuated. As a result, simplified modification of patterns of features in a CAD solid model is facilitated.

Abstract: A method, apparatus, and article of manufacture provide the ability to conduct a sweep operation in a computer-implemented solid modeling system, A 3D non-planar surface is created. A path for a sweep operation is created. A profile for the sweep operation is created. The 3D surface is selected for use as a guide. An angle between the profile and the 3D non-planar surface is calculated. A sweep operation is conducted wherein a twist of the profile is maintained within a pre-defined range of the angle.