This feature performs Catmull-Clark subdivision on the selected entities using Pixar's OpenSubdiv library.
Depending on the entities you select, the tool will have different effects.
Groups and Components
If you preselect a group or component, this tool will create a locked subdivided high-resolution mesh that can be edited using a low-resolution proxy mesh. The subdivided mesh will update in real-time if you edit the mesh using any of the Artisan tools.
To edit the mesh, double-click it and the Subdivision Settings dialog should open and the proxy should become visible.
When you are temporarily finished editing, but plan to make more changes later, simply close the group or component. The Subdivision Settings dialog will close automatically. (If the Artisan Select Tool is active, you can do this by double-clicking empty space). This will allow you to continue editing the proxy later. When you want to edit the object later, simply double-click it. There is no need to undo / redo the subdivision to toggle it.
Click the 'Commit' button if you want to permanently remove the proxy and edit the high-resolution mesh directly.
Click the 'Remove' button to remove the subdivided mesh and revert back to the original geometry only.
When the Subdivision Settings dialog is visible, you can choose to display the subsurface only, proxy only, or both at the same time.
If you select faces prior to activating this tool, only the selected faces will be subdivided and smoothed. No proxy is created in this case. You can apply more iterations by repeatedly clicking the 'Subdivide and Smooth' toolbar button. Adjacent faces that were not selected will be automatically split using soft edges. This allows the geometry to edited later in a predictable way without vertices ripping apart.