ABSTRACT
Mid-and lower-level software applications have also seen increasing sophistication in their ability to manipulate 3D models. Mainstream commercial CAD packages now allow users to rapidly develop 3D models at different levels of detail. It is also possible to perform 4D analysis by linking the 3D models to scheduling packages and/or by manipulating the 3D objects using layer functions. 3D technology has also enhanced lower-end CAD systems, perhaps best evinced by the sub-US$100 home design CAD packages sold in retail stores. These systems allow homeowners to rapidly build and render 3D models of their homes, producing drawings usable by contractors. Cost and capability are no longer considered a barrier for any firm that wishes to employ 3D/4D tools.
