Abstract: A computer program product (400) and system executing/implementing the same provides a visual depiction of a part or assembly or scene (200) upon a display device. Upon execution, the program establishes for the system (1) a design flow system (404) comprising an object for each of one or more shapes, and (2) a modeling kernel (410). The modeling kernel comprises multiple concurrently available geometric engine types (432). The program enables performance of operations upon differing shapes in a same assembly, the differing shapes being generated by differing geometric engine types and the operations upon the assembly being performed by invoking the concurrently available geometric engine types in the modeling kernel. The the design flow system of the program also facilitates section of which of the multiple geometric engine types should attempt to perform an operation with respect to the one or more shapes.