Ghost mode gives parts transparency, but unlike purely transparent geometries, ghosted geometries in the model area can no longer be selected. That means you can select and dimension the part behind the ghosted part. These ghosted geometries are displayed with a grayed out icon in the structure.

Enable the ghosting mode via Start > Selection mode > Ghost or select the relevant objects and click the button Start > Selection > Ghost. Alternatively you can use the key combination [ALT]+[G] to ghost the object at the cursor position (no previous selection required).

To make all ghosted parts visible again, the Unghost function can be selected in the Show > Hide area. The Ghost mode is also disabled by selecting the Show all function. The key combination [ALT]+[S] will unghost all parts one by one in reverse order. A selective deactivation of the Ghost mode is made possible by selecting corresponding geometries in the structure and then selecting the Unghost option in the Selection area.