Psychtoolbox>Screen.{mex*} subfunction

Screen(‘ShowCursorHelper’, screenIndex [, cursorshapeid][, mouseIndex]);

This is a helper function called by ShowCursor. Do not call
Screen(‘ShowCursorHelper’), use ShowCursor instead.
Show the mouse pointer. If optional ‘cursorshapeid’ is given, select a specific
cursor shape as well.
If optional ‘mouseIndex’ is given, setup cursor for given master mouseIndex
device (Linux only).

###See also: HideCursorHelper