IN THIS CHAPTER
Introducing parametric drawing
Applying geometric and dimensional constraints
Editing parametric drawings
A few releases back, AutoCAD added a set of parametric drawing tools, and, offhand, I can’t think of a more significant new feature in recent years. In fact, if you work primarily in 2D, and especially if you’re in the manufacturing business, parametrics in AutoCAD (and, to a very limited degree, in AutoCAD LT) might just be the most significant new feature ever since the beginning of orthographic engineering drawings, generally attributed to the Roman architect Marcus Vitruvius in the 1st century BC. Contrary to popular opinion, I am not so old that I knew him personally.
Parametric tools allow you to create relationships between geometry in a drawing. These relationships help to constrain and restrict changes to a design. If you know what I’m talking about, you’re probably pretty interested in finding out more about what you can do with parametrics in AutoCAD. If, on the other hand, you think parametrics are the folks who show up when you dial 911, the following paragraphs should straighten you out.
Imagine this scenario: Your boss has been in a meeting all morning with an important client. At two minutes before noon, they emerge. Your boss hands you a marked-up printout and rather imperiously commands you: “We need these 12 dimensions changed and the drawing updated by the time we return from lunch.” ...