ShowCursor

Psychtoolbox › PsychBasic

oldType = ShowCursor([type] [, screenid][, mouseid])

ShowCursor redisplays the mouse pointer after a previous call to
HideCursor. If the optional 'type' is specified, it also allows to alter
the shape of the cursor. See following sections for details.

The optional 'mouseid' allows to select which mouse cursor shall
be redisplayed or changed in visual appearance. This only makes sense
if you have multiple visible mouse cursors and is currently a Linux only
feature.

The return value 'oldType' is always zero, as this query mechanism is not
supported with PTB-3. Just returned for backwards-compatibility.

OSX, WINDOWS, LINUX

Cursor shape can be selected. Four types are defined by name:

'Arrow' = Standard mouse-pointer arrow.
'CrossHair' = A cross-hair cursor.
'Hand' = A hand symbol.
'SandClock' = Some sort of sand clock/hour-glass whatever...

Apart from that names, you can pass integral numbers for type to select
further shapes. The mapping of numbers to shapes is operating system
dependent, therefore not portable across different platforms. On
MS-Windows, you can select between number 0 to 7. On Linux/X11 you can
select from a wide range of numbers from 0 up to (at least) 152, maybe
more, depending on your setup. See the C header file "X11/cursorfont.h"
for a mapping of numbers to shapes. Passing invalid numbers can create
errors. On OS/X, numbers between zero and 17 are currently valid. You
can find a list of mappings from type to number for OS/X at:
http://developer.apple.com/documentation/macos8/HumanInterfaceToolbox/Ap
pManager/ProgWithAppearanceMgr/Appearance.9d.html#10244

LINUX

Linux allows for display and handling of multiple mouse cursors if your
X-Server is of version 1.7 or later.

If provided, the optional "type" argument changes the cursor shape to:
0: Arrow
1: I Beam
2: Cross
3: Plus
4: Watch
5: Arrow
128: P
300: Beachball 1/4
301: Beachball 2/4
302: Beachball 3/4
303: Beachball 4/4
400: fat arrow
401: fat I Beam
Type 0 (and 5 for backward compatibility) is predefined as the standard
arrow cursor. The rest return whatever Apple's GetCursor(type) finds in
the System or Matlab's resource forks. If nothing is found, the type is
reset to 0. The fat arrow and I beam are copied from the "Fat Cursors v
1.2" control panel created by Robert Abatecola, 5106 Forest Glen Drive,
San Jose, CA 95129.

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