This is a post by Emma Rudeck on the Concurrent Engineering Site.
Until recently the use of direct modeling was limited to animation. But, now, designers of all types are starting to use direct modeling. Improvements in the tools now mean it is easier that ever before for designers to create the products that their customer’s want.
WHAT EXACTLY IS DIRECT MODELING?
Before we get into a discussion of why direct modeling is useful, it might be helpful to understand what exactly it is. Put simply, direct modeling is a CAD method that allows designers to interact directly with the geometry of the model. This means they can manipulate it by pushing, pulling, or twisting.
So, unlike parametric modeling, where a feature’s final geometry has to be built into the steps that create the final model, direct modelling allows the features geometry to be modified without having to edit the interim model stages.