Worldview: An Integrated Geometric-Modeling/ Drafting System

Worldview is a computer-aided architectural and engineering design system that combines the power of geometric modeling utilities with the intuitive design and communication capabilities of drafting utilities. This article describes the basic design concepts and implementation of the system, achieved by representing the designed artifact nonredundantly in a three-dimensional "world" and manipulating it through multiple two-dimensional "viwes." The world consists of a collection of shapes that store all the formative information pertinent to the designed artifact, while the views consist of images of selected shapes, generated through particular two-way mapping transforms. Several views that dapict the same set of shapes through different transforms can be displayed simultaneously, using multiple, dynamic, user-defined windows, thereby enabling addressability of points in the 3D world. Views also include such design and communication aids as dimension lines, construction lines, annotations, and graphic symbols to enhance the visual content of the images without encumbering the representation of the shapes themselves. Modifications applied to the shapes through any view are immediately apparent in all other views in which the shapes are imaged. The shapes are represented by a data structure based on the hybrid-edge data model, which facilites the integration of points, lines, surfaces, and volumetric bodies into one formative hierarchy. The integration of drafting and modeling simplifies the use of powerful modeling utilities by designers, facilitates the communication of the designed artifact, and enhances the integrity of the design as a whole.