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The History of CAD Software

Although PCs and Macs steadily increased in power throughout the 1980s and AutoCAD continued to gain substantial market share in the 2D CAD software market (despite being ridiculed by the leading CAD software vendors) the general lack of processor power and especially the poor graphics performance compared to UNIX workstations meant that it was not to be until the next decade that PCs would have their revolutionary effect on the CAD software industry.

Throughout the 1980s, the new generation of powerful UNIX workstations and emerging 3D rendering was inevitably shifting the CAD software market to 3D and solid modeling. In 1981 Unigraphics released its UniSolids CAD software based on Voelcker's PADL-2 CSG solid modeling kernel and then in 1982, Ian Braid, Charles Lang and the Shape Data team in Cambridge, England, released the Romulus b-rep solid modeler; the first commercial solid modeling kernel designed for straightforward integration into CAD software. Romulus incorporated the CAM-I AIS (Computer Aided Manufacturers International's Application Interface Specification) and was the only solid modeler (other than its successor Parasolid) ever to offer a third-party standard API to facilitate high-level integration into a host CAD software program. Romulus was quickly licensed by Siemens, HP and several other CAD software vendors. The first version of IGES had been published in 1980 but already the emerging shift to 3D CAD software using solid models, and the need for such CAD software to manage product data such as material properties, surface finish, engineering tolerances etc., was creating a need for a new data exchange standard. In 1984 the PDES (Product Data Exchange Specification) initiative was started in Europe to address the new needs.

In 1985, CATIA Version 2 was released as a CAD software program independent of CADAM and another French CAD software vendor, Matra Datavision (founded in 1980), released its Euclid-IS solid modeling 3D CAD software which used a unique hybrid mix of planar faceted models (for speed) with CSG data-structures. The Romulus solid modeling kernel went through several upgrades to add assembly management, instancing, improved blending and b-spline surfaces before being retired in 1986. Also in 1985, Evans & Sutherland, who had maintained close relations with Charles Lang and Ian Braid for several years and was interested in developing CAD software to supplement its graphics terminals and simulator business, acquired Shape Data. E&S soon commissioned Bernard Solomon and his team at Shape Data to begin developing the Romulus-D 3D CAD software. Romulus-D was an innovative 3D CAD software program built on the Romulus solid modeling kernel. Romulus-D ran on Apollo workstations and used Apollo's DOMAIN networking to provide the CAD software industry's first network-enabled 3D CAD software, including assembly modeling, fully distributed product configuration management and change control functions.

By 1985 the CAD software industry seemed to have settled into a comfortable trend, with incremental improvements in software functionality taking advantage of continuing advances in computer hardware performance. Profit margins were high as CAD software prices stayed high despite falling hardware prices and sales growth was strong. Computervision, with annual revenues exceeding $350M, was the market leader ahead of GE/CALMA, Applicon and Intergraph followed by McDonnell-Douglas/Unigraphics and IBM/CATIA. Then, in 1985, a new and very aggressive 3D solid modeling CAD software vendor, Parametric Technology Corp. (now PTC), appeared in the market - commercial reality was arriving and in many ways the industry would not be the same again.