Parametric modeling is a computer aided design (CAD) software design tool that saves time—it eliminates the need for a design engineer to constantly redraw a design every time one of the design’s dimensions change.
This tool was developed by Rhino, a software program that evolved from AutoCAD.
This tool lets designers modify the entire shape of their design at once, not just individual dimensions one at a time.
But there are some drawbacks with parametric modeling tools. Designers must often anticipate potential design changes and define features accordingly. Plus, the designer must define the relationships between features. For complex designs, capturing design intent can be a challenge.
So, developers created a tool known as direct modeling. This tool provides a geometric-based modeling strategy, rather than a feature-based format so that designers can quickly define and edit geometry.
Pro/ENGINEER (Creo 2.0 and higher) and SolidWorks (2012 and newer) offer direct modeling on top of existing feature-based parametric modeling. Direct modeling lets copy, move, split, replace, offset, push, and drag geometry in any way they need.