ABSTRACT
Computer-aided design and engineering systems simplify and expedite the creation of part geometry. In a process similar to making a drawing or creating a physical model, designers construct three-dimensional computer-based models which provide a data base of graphic and nongraphic part information. To illustrate how to construct the graphics model on an interactive computer graphics system, this chapter uses the command syntax related to Computer-vision’s CADDS 4 software. Mode refers to Model or Draw mode. Model mode is default and is used to define the model by the designer. The DELETE ENTITY command deletes graphical entities from all drawings of a part, both model and drawings. The CROSSHATCHING command provides for defining a cross-sectioned surface by inserting nonindependent lines within the boundaries of that surface. The grid commands provide visible grid points on the screen which can be used for reference only, or the grid may be active, which means that only grid points can be digitized.
