Switch operations between actions and tools

Maya makes a distinction between tools and actions.

Tools work continuously: any clicks or drags you make while the tool is active apply the tool.
For example, the selection arrow is a tool. Any clicks or drags in the view window while the selection arrow is active performs a selection.
Actions are immediate, “one shot” operations applied to the selection. Most items in the menus are actions.

For example, many items under the Edit Curves, Surfaces, and Edit NURBS menus can be converted from actions to tools (or vice versa).

You can distinguish tools from actions by the names of menu items. Tools have Tool in the menu entry title. Actions do not. For example, the Curve Editing Tool is a tool, but the Attach Curves menu item is an action.

If you change an action to a tool, Maya adds Tool to its name in the main menu and option window. If you change the tool back to an action, Tool is removed from the name. Regardless of whether a feature is a tool or action, the order in which you select objects or components stays the same.

Option windows for tools and actions include an Edit option menu at the top of the window that allows you to pick between tool and action modes. Currently, only actions can be switched to tool mode. Therefore, for tools (for example, Birail Surface Tool), the Edit option menu is disabled.

To change actions to tools throughout Maya

Select Window > Settings/Preferences > Preferences.
In the Categories list of the Preferences window, click Modeling, then turn on Everything is a Tool.

Afterwards, you’ll notice more NURBS menu items have Tool in their names. To return to action-based behavior, turn on Everything is an Action in the same Preferences window.

If you turn on Mixed, a setting within each option box specifies whether the menu item is a tool or action.

To convert a single menu item from an action to a tool

Open the item’s options window and select Edit > As Tool.
To return to action-based behavior, select Edit > As Action.
If the options window doesn’t have an Edit menu or the As Tool and As Action items are dim, the action (or tool) can’t be converted.

The setting in the Options window takes precedence over the Preferences window. Changing from actions to tools or vice versa works immediately.

When you use an action converted to a tool, Maya sets an object and component selection mask appropriate for the tool. Maya returns to the prior selection mask after you finish using the tool.

Tool options

If you change an action to a tool, the options window for that tool displays two extra options:

Exit Upon Completion
If this option is off, Maya’s focus remains on the tool after you finish using it. You can use the tool repeatedly without selecting it again.

If this option is on, Maya exits the tool. The following menu items, when used as tools, have Exit Upon Completion as the default option.
All other tools, including actions converted to tools, use Auto Completion as the default.
Auto Completion
If this option is on, you don’t have to press Enter (Linux^® and Microsoft^® Windows^®) or Return (Apple^® Mac OS^® X) to finish a modeling task. The tool completes its task as soon as you select enough objects or components.