7.3 The catalogue

The bundled catalogue is global and read-only. The two + Add … buttons in the Device tab ask a different question from + Projector in the 3D tab:

Table 7.1 Two questions, one dialog.

Where	Asks	Offers
3D tab, + Projector	Which definition do I place?	This project + Catalogue
Device tab, + Add …	What new definition do I create?	Custom + Catalogue (cloned to edit)

Cloning from the catalogue copies it under a fresh id, so your edits never touch the catalogue and a project stays self-contained.