This is a general introduction to sub-object selection. For specific information, see Editable Mesh, Editable Patch, Editable Poly, and Editable Spline; for a discussion of NURBS sub-object selection, see Sub-Object Selection.
When you model an object, often you edit a portion of its underlying geometry, such as a set of its faces or vertices. Or when you are working with a model, you may want to apply mapping coordinates to a portion of its underlying geometry. Use the methods described in this topic to make sub-object selections.
Left: A selection of face sub-objects
Middle: A selection of edge sub-objects
Right: A selection of vertex sub-objects
You can access sub-object geometry through a variety of methods. The most common technique is to convert an object into "editable" geometry such as a mesh, spline, patch, NURBS, or poly object. These object types let you select and edit geometry at the sub-object level.
If you have a primitive object and want to retain control of its creation parameters, you can apply a modifier such as Edit Mesh, Edit Poly, Edit Spline, Edit Patch, or Mesh Select.
The Line Spline and NURBS curves and surfaces are the exception: you can edit their sub-objects as soon as you create these kinds of objects.
You choose a sub-object level in the stack display. Click the plus sign that appears next to the name of an object that has sub-objects. This expands the hierarchy, showing the available sub-object levels. Click a level to choose it. The name of the sub-object level highlights in yellow, and the icon for that sub-object level appears to the right of both its name and the name of the top-level object.
Stack display shows the sub-object hierarchy, letting you choose a sub-object level.
Editing at the Sub-Object Level
When you edit an object at the sub-object level, you can select only components at that level: vertices, edges, polygons, and so on. You can’t deselect the current object, nor can you select other objects. To leave sub-object editing and return to object-level editing, click the top-level name of the object in the modifier stack, or click the highlighted sub-object level.
Click the top-level object name to exit sub-object editing.
To make a sub-object selection:
These methods assume the object has sub-object levels. If the object has no sub-object levels (for example, a primitive such as a sphere), the + icon is not present. In that case, you need to collapse the object or apply an Edit modifier before you can edit its sub-object geometry.
There are two alternative ways to go to a sub-object level:
To exit a sub-object level, do one of the following:
If you think you’ve turned off sub-object editing but top-level object selection is still not restored, it might be due to the following reasons: