Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!usc!sdd.hp.com!hp-pcd!hpcvlx!ben
From: ben@hpcvlx.cv.hp.com (Benjamin Ellsworth)
Newsgroups: comp.windows.x
Subject: Re: XWarpPointer revisited.....
Message-ID: <100920272@hpcvlx.cv.hp.com>
Date: 16 Jan 91 17:37:07 GMT
References: <9945@ncar.ucar.edu>
Organization: Hewlett-Packard Co., Corvallis, OR, USA
Lines: 29


> Is it simply because the user can become confused with the visual
> effects?

I think so.  The problem is that it seriously disturbs the "direct
manipulation" paradigm.  The cursor is always attached to the
mouse--moving the mouse moves the cursor.  When you warp the cursor, you
have caused the cursor to move without moving the mouse.  This weakens
the perception that the two are connected.

There are also perceptual issues regarding "Where'd that darn cursor
get to anyway?!"  When the cursor is attached to the mouse, the user
knows where the cursor is--it's right where he or she left it.  When
the cursor is warped, the user has to figure out where it went.

Lastly, you can run into a problem between relative and absolute
locator devices.  What happens if the user is using a tablet for
locator input (instead of a mouse) and the cursor is warped?  Do you
have a mechanical arm come out and adjust the tablet stylus for the
user?  ;-)

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