Controlling cursor speed when using a joystick

Mon May 16 18:35:30 UTC 2011

Erin,

Well, I was mighty puzzled when it seemed that my 
code made the joystick behave oddly, so I am glad 
that you took the trouble to test it further and 
report back that the joystick always behaves that way, thanks.

But that doesn't help you solve your problem.  It 
does seem odd to me that the joystick behaves 
that way, it seems to me that if that behavior 
were common then other E-Prime users would have 
made a note of it.  So I hope we hear from other 
E-Prime users with joysticks about whether as a 
rule the screen cursor simply mirrors the current 
joystick position, or if instead the cursor 
continues moving as long as the joystick is 
pushed off-center.  If joysticks for other users 
work in the "unstuck" way, then I would suspect 
the problem has something to do with your 
particular joystick and you might want to try 
another.  To that end, you might ask PST support 
again what joysticks they recommend.

BTW, just for kicks I started to make a second 
demo to follow Matt Lenhart's suggestion to use 
SetCursorLimits.  But I don't see how that could 
possibly work.  If cursor limits are set to the 
current cursor position, then any attempt to move 
the cursor any farther from center will result in 
no movement at all, so there will be no new 
cursor data with which to set new cursor 
limits.  E.g., suppose the cursor is at (100, 
100), so you set one corner of the cursor limit 
to (100, 100).  The subject then moves such that 
the cursor should move to, say, (90,90).  But 
that is beyond the current limit, so the cursor 
stays at (100, 100), and the system lacks any 
information regarding the subject's attempt to 
move the cursor and so the cursor just stays 
where it is.  (Of course, it would still detect 
inward movements, but that hardly helps you.)  So I gave up on that idea.

So I am afraid that I am out of ideas.

-- David McFarlane, Professional Faultfinder

At 5/13/2011 04:06 PM Friday, Erin wrote:
>Thank you for the pointers.
>
>I had already tried slowing down the cursor speed in windows.  This
>successfully slows down the mouse cursor speed within E-Prime, but has
>no effect on the joystick.  There are not similar controls for
>joystick sensitivity in the game controller section of the Windows
>control panel.
>
>So, I did more testing of the joystick in E-Prime.  Turns out, the
>cursor is "stuck" to the joystick even without David's code.  His code
>just slowed down the cursor enough that the effect was much more
>noticeable.  Before, the cursor was so sensitive that only very small
>joystick moments were needed to move the cursor and make an image
>selection, and the "backtracking" behavior was less apparent.  (The
>experiment is set up to re-center the cursor on every trial, also
>making it less obvious).  So, when the cursor speed is slowed, the
>range of the cursor is very diminished when using the joystick- you
>can't even reach the edge of the screen with the cursor (which is
>obviously a problem).
>
>Anyone have any ideas of how to make the joystick only "push" the
>cursor forward in E-Prime, and not "pull" it back when the joystick is
>moved back towards center?
>
>Erin
>
>
>
>
>On May 13, 4:34 am, Michiel Spape <Michiel.Sp... at nottingham.ac.uk>
>wrote:
> > Hiya,
> > Two points here:
> > - For one, I'd suggest just going a bit 
> higher into Windows and setting the mouse 
> and/or joystick sensitivity. I remember this 
> was quite common in Win98 or something like 
> that, but it seems to be missing in Windows XP. 
> Nevertheless, I very much doubt you won't be 
> able to find a little programme that sets the 
> cursor and/or mouse sensitivity to a lower 
> resolution. All in all, that would be a lot easier for your purposes.
> > - Second, it seems to me that the main issue 
> with joystick vs mouse is the joystick being 
> centred at a certain position. I think - but 
> could be mistaken? - that in order to do this, 
> you might want to change the script so that the 
> X0, Y0 are not overwritten, but rather that you 
> change the cursor position by the deviation 
> with the beginning of the trial. So, if the 
> cursor is at pixel 320,240 in the beginning 
> (i.e. centre at 640x480 resolution), then at 
> next polling the cursor is at 321,240 (1 pixel 
> to the right), the cursor should (as it does 
> currently) move one pixel to the right. 
> However, at the polling after that, given that 
> the subject didn't move the joystick (i.e. 
> polling says it's the same as previous 
> polling), then the difference of 1,0 related to 
> the *startposition* should still cause it to 
> move 1 more to the right (i.e. 322,240). I'm 
> terrible at messing with someone else's code, 
> but if you understand what I'm saying, this 
> shouldn't be too hard to implement (just keep 
> comparing to the start position, rather than 
> the previous position). More hardcore, by the 
> way, and likely better (given that most 
> joysticks tend to be round, rather than square) 
> would be to calculate the angle and amplitude 
> of the joystick, then move the cursor with that information.
> >
> > Hope that helps,
> > Mich
> >
> > Michiel Spapé
> > Research Fellow
> > Perception & Action group
> > University of Nottingham
> > School of Psychologywww.cognitology.eu
> >
> > -----Original Message-----
> > From: e-prime at googlegroups.com 
> [mailto:e-prime at googlegroups.com] On Behalf Of David McFarlane
> > Sent: 12 May 2011 20:38
> > To: e-prime at googlegroups.com
> > Subject: Re: Controlling cursor speed when using a joystick
> >
> > Just thinking through this a bit further, if we knew exactly what
> > data the joystick sent to the PC, and where (e.g., what I/O port)
> > that data appeared, then in principle we could write code to affect
> > the cursor in whatever way we wish.  But at the moment we lack that
> > technical information.
> >
> > -- David McFarlane, Professional Faultfinder
> >
> > At 5/12/2011 03:34 PM Thursday, you wrote:
> > >Erin,
> >
> > >Thanks for testing that out, and posting back so quickly.  I don't
> > >have any joystick myself, so I don't think I can help any
> > >further.  I would not have expected your result, clearly the
> > >joystick does not simply emulate the mouse otherwise it would just
> > >work (and in that case you would not need a code solution in the
> > >first place).  Is there a separate Windows "control panel" for the
> > >joystick that you can use to control its settings?  Other than that,
> > >if it were me I might try another joystick, or start Googling around
> > >for more technical background on joysticks in general and then use
> > >that knowledge to devise a solution.
> >
> > >Good luck,
> > >-- David McFarlane, Professional Faultfinder
> >
> > >>hi David,
> > >>Matt was the one helping me.
> >
> > >>Thank you very much for the sample code!  I tried it out, and it does
> > >>change how the cursor moves.  For the mouse, it slows it down quite
> > >>perfectly.  For the joystick, it also slows down, but there is an
> > >>interesting effect. The mouse cursor is basically "stuck" to the
> > >>joystick.  Normally, when you move the joystick left, the cursor
> > >>continues to move left, even when the joystick handle is held in a
> > >>constant left position.  With your modification, the mouse cursor
> > >>moves only when you move the joystick.  So, the cursor will move left
> > >>as you move the joystick left, but when you stop the joystick, it
> > >>stops.  And, when you let the joystick go back to it's resting
> > >>position, the cursor actually backtracks back to it's original
> > >>position.  This is an interesting feature, but not what will work for
> > >>my particular application. (However, I'm sure it's exactly what
> > >>someone else might need).  It would be absolutely perfect if the
> > >>cursor could be "unstuck"  from the joystick, so that the joystick
> > >>just directs the cursor to move forward in whatever direction the
> > >>joystick is pointed.  Any suggestions?  Again, thank you so much!
> >
> > >>Erin
> >
> > >>On May 12, 1:58 pm, David McFarlane <mcfar... at msu.edu> wrote:
> > >> > Erin,
> >
> > >> > Thanks for posting the full information from PST, that helped (can
> > >> > you let us know which staff member helped you?).  I might have come
> > >> > up with the Mouse.SetCursorPos approach myself, but not the
> > >> > Mouse.SetCursorLimits approach, that approach seems a little wacky to
> > >> > me but what do I know?.
> >
> > >> > As for Mouse.SetCursorPos, this posed a nice little puzzle, so I
> > >> > knocked out a quick demo, and here is the inline that I came up
> > >> > with.  (Just to have a mouse click to respond to, I preceded the
> > >> > inline with a TextDisplay called StimText, set to Duration of 0 and
> > >> > mouse with Time Limit of (infinite)):
> >
> > >> > 
> /----------------------------------------------------------------------\
> > >> > ' Code to modify the rate of mouse movement.
> >
> > >> > Const  LoopDelay as Long = 0
> > >> > Const  CursorMoveFactor as Single = 0.5
> >
> > >> > Dim  x0 as Long, y0 as Long
> > >> > Dim  x1 as Long, y1 as Long
> >
> > >> > Mouse.GetCursorPos x0, y0  ' initialize
> > >> > Do While (StimText.RT = 0)  ' replace this with your exit condition
> > >> >      Mouse.GetCursorPos x1, y1
> > >> >      x0 = x0 + (CursorMoveFactor * (x1 - x0))
> > >> >      y0 = y0 + (CursorMoveFactor * (y1 - y0))
> > >> >      Mouse.SetCursorPos x0, y0
> > >> >      Sleep LoopDelay
> > >> > Loop
> > >> > 
> \----------------------------------------------------------------------/
> >
> > >> > I expected to find some cursor movement artifacts, but it really
> > >> > worked rather smoothly.  As you can see, I didn't even really need
> > >> > the LoopDelay, but I left it there just in case.
> >
> > >> > -- David McFarlane, Professional Faultfinder
> >
> > >> > At 5/12/2011 01:03 PM Thursday, you wrote:
> >
> > >> > >I want to control the speed the cursor moves when controlling it with
> > >> > >a joystick.  I set the joystick to emulate the mouse in my experiment
> > >> > >(inline Joystick.AttachToMouseCursor = True).  The joystick is quite
> > >> > >touchy, and causes the cursor to move very quickly across the screen.
> > >> > >For my experiment, I need the cursor to only move slowly, no matter
> > >> > >how much the joystick is moved.
> >
> > >> > >I tried decreasing the mouse sensitivity settings on my computer.
> > >> > >This slowed the cursor down when using 
> the mouse within my experiment,
> > >> > >but had no effect on the joystick.  I also tried increasing the
> > >> > >resolution display of my experiment (giving the cursor "further" to
> > >> > >travel)- also no effect.  I have also tried adjusting the sensitivity
> > >> > >of my joystick, but the cursor is still too fast.
> >
> > >> > >E-Prime support suggested the following: "E-Prime does have some
> > >> > >limited options for positioning the mouse cursor and limiting its
> > >> > >boundaries. We could try to use a combination of the two to make the
> > >> > >mouse cursor move more slowly. However, 
> this would require significant
> > >> > >scripting and could result in the cursor movement not being smooth"
> >
> > >> > >My main question: Is anyone aware of a simpler way of controlling the
> > >> > >cursor speed in E-Prime?
> >
> > >> > >If not, here is further information on this method:
> >
> > >> > >E-Prime help suggested the following:
> > >> > >"I would recommend taking a look at the MouseDevice.SetCursorLimits
> > >> > >and MouseDevice.SetCursorPos topics in the E-Basic Help (accessed via
> > >> > >the Help menu). The former will allow you to specify boundaries for
> > >> > >the cursor, and the latter will allow 
> you to position the mouse cursor
> > >> > >in a specific area. You could use a combination of the two to first
> > >> > >limit the movement of the cursor so that it does not immediately move
> > >> > >to one edge of the screen, and then use SetCursorPos to move the
> > >> > >cursor move slowly. You could also slowly expand the cursor limits as
> > >> > >the cursor hits the maximum in one direction. This would allow you to
> > >> > >give the appearance of the cursor moving more slowly. To do this, you
> > >> > >would have a loop that continuously 
> checks the cursor position against
> > >> > >the limits that are set, and expand the 
> limits in one direction as the
> > >> > >cursor hits that limit. This would require significant scripting and
> > >> > >could result in the cursor movement not being smooth."
> >
> > >> > >I took a look at the MouseDevice.SetCursorLimits and
> > >> > >MouseDevice.SetCursorPos help, and I 
> understand how this would work in
> > >> > >theory.  However, I am very new to programming, and I am afraid that
> > >> > >the scripting involved is a bit over my 
> head.  If anyone can offer any
> > >> > >advice or pointers, it would be very appreciated.  thank you!
> >
> > >> > >Erin

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