Touch-pad expectations

Hal Murray hmurray at
Fri Feb 4 22:15:25 EST 2011

Frequently, I find the touch-pad on a XO-1 to be extremely frustrating to use 
on cursor intensive tasks.  I'm trying to figure out if this is something I 
should be screaming and shouting about (and rubbing it in your collective 
noses) or if I should shut up and get used to it.

I think there are two problems.

One is that there is no feedback when the recalibration is going on, so I 
keep trying to do whatever I'm working on.  That screws up the calibration 
which makes me try harder which spirals downhill.

The other may be a fundamental problem with touch-pads as compared to mice.  
The problem is that I have troubles making long motions that I expect should 
to work.



I've used a mouse for 30+ years.  I don't have a (real/non-XO) laptop so my 
experience with touch pads is limited to work/hacking/play with a XO-1.

I worked at Xerox many years ago shortly after Card and Moran and Newell did 
the early work on why a mouse was so much better than cursor keys and such.  
I've had lunch more than once with one of them.  (I forget which one(s).)  
His stories of how to screwup a mouse are entertaining...

The key idea with a mouse is that your big arm muscles are used for the long 
motions and the fine finger muscles do the delicate pixel-or-two size 
motions.  I don't see anything like that with the touch-pad so maybe my 
expectations are off scale.  Or maybe some velocity/scaling magic is supposed 
to fix that mess.  Or ...


I play Implode on the XO.  It's a wonderful cursor test.

I play the middle game.  (I'm not smart enough for the big game.)  To make it 
interesting, I add a few more rules/constraints...  They are only in my head.
0: minimize the total number of clicks
1: tallest last-click wins
2: assign a priority to the colors, so for the same height, red beats blue...
3: Of course, faster is better.  (Who knows what the scale is.)
4: When you make the last click, see how fast you can get to the new-game 
button.  You get an extra point (on some scale) if you get there before it 
has finished making the face.
  [I'll say more if anybody wants.  But try your own rules first.]

That last step usually involves a long motion.  The new-game button is on the 
top.  You are probably clicking down near the bottom.

It's cheating to pre-position the cursor up near the top so you have a 
shorter motion to the new-game button.  Or at least distracts from your rule 
3 points.  But if you ignore that, it works pretty well.

Anyway, if anybody wants a cursor test case, I suggest Implode with some 
extra rules/constraints like the above.  The details don't matter.  Pick your 
own rules if you don't like mine  It's some combination of cursor and brain 
limited, and a lot of the time, the cursor is the limiting factor.

The key step may be that you never have to type anything.  I work with my 
right finger on the touch-pad and my left finger on the left button.


Back to the big picture...

If I use a system with a touch-pad type cursor, do I have to recalibrate my 
long-motion expectations relative to a mouse?

Do normal laptops have a recalibrate mode?  If so, do they have any feedback 
while they are recalibrating?

These are my opinions, not necessarily my employer's.  I hate spam.

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