Design Nomenclature / Digital Model Making
Direct Modeling
Also called explicit modeling, history-free modeling, push-pull modeling
This entry has not been translated yet and is shown in English.
Editing the boundary geometry itself — grab a face, push it — with no feature tree to replay. Recognition tools infer intent, reading a ring of faces as a hole, so the edit stays sensible. Excellent on imported or dumb solids: there is nothing to break and nothing to parametrize.
In practice
The two are not exclusive; most CAD does both, and “direct edit” is often a feature inside a history tree. Arguments about which is better are arguments about whose files you inherit.
Not to be confused with
- Parametric ModelingA model recorded as an ordered sequence of operations bound to editable parameters and to references on earlier geometry. Change a dimension and the tree replays. The power and the fragility are one thing: a reference to a face that a later edit renames or deletes breaks the rebuild.
- Solid ModelingRepresenting a part as a closed watertight volume: trimmed faces stitched along shared edges, with an inside and an outside the kernel can guarantee. Volume, mass, and interference become computable. Every operation is validated against that closure, which is why a CAD boolean either succeeds cleanly or refuses.