Callback

Description

Execute (Command)

Fired when the command is invoked. Gets the command arguments (if any), executes the command, and returns the result (if any).

Init (Command)

Optional. Fired the first time a command is invoked after the plug-in is loaded. Specifies the return value and arguments of the command.

Undo

Optional, C++ API only. Fired when a custom command is being undone. The return value is ignored.

Redo

Optional, C++ API only. Fired when a custom command is being redone. The return value is ignored.

TermUndoRedo

Optional, C++ API only. Fired when a custom command undo event is removed from the Softimage undo stack. This callback is typically used to release any memory required for undoing this command. The return value is ignored.

Term

Optional. Fired when a plug-in is removed from Softimage (just before Softimage calls XSIUnloadPlugin). For example, Term is triggered when you exit Softimage or unload the plug-in.

Unload, Reload

Fired when the plug-in is cached (reloaded) and uncached (unloaded). By default, all plug-ins are cached, but users can remove a plug-in from the cache (by right-clicking a plug-in in the plug-in tree and clearing the Cached checkmark).