X-Mailer: ELM [version 2.3 PL11]
Newsgroups: bit.listserv.uigis-l
Date:         Wed, 19 Aug 1992 17:37:38 CDT
              List" <UIGIS-L@UBVM.BITNET>
From:         "Tim McGrath" <tmcgrath@TMCGDNELNC.CR.USGS.GOV>
Subject:      Re: GIS User interfaces
X-To:         uigis-l%ubvm.bitnet@mitvma.mit.edu

> From: Jay Sandhu <esri!adriatic!jay@UUNET.UU.NET>
>
> All computer software have an interface. The question
> to ask is, "Is the interface appropriate to solve
> the task that the software is designed to solve?".
> I think (know) that the GIS community is no different than
> any other computer industry at this moment in its
> approach to solving the "interface" problem. That is,
> the current approach IS to provide "interface building"
> tools to the system builders.

At least one system, Khoros, takes a different approach.  Khoros is
primarily an image processing system.  The graphical user interface,
Cantata, is more of a "tool building" interface to system users.  This
approach allows users (not system builders) to literally link "glyphs"
of the available commands and routines together intelligently to
solve a task.  By "intelligently" I mean that the "glyphs" connect to
each other through sockets which basically represent the arguments to
the command or routine.  Required commands have a highlighted socket,
optional ones do not.  The output socket of one glyph can be directly
connected to the input socket of another glyph by clicking with the
mouse first upon the output socket, and then upon the input socket.
Many glyphs require no other input from the user.  Optional form
style menus can be brought up for each glyph to further costumize the
operation of the glyph.  Sets of connected glyphs form a "workspace"
for a specific analysis or task and can be saved for future use.
Changes to the input set of glyphs are all that is required to use
the workspace on data other than that with which it was created.
Routines can be chosen from a menu and glyphs are automatically created
for each and placed upon the workspace.  Links between glyphs can be
moved or dropped, or glyphs can be removed, all with clicks of a mouse.

None of this means that Khoros is "simple" to use.  There is still a
learning curve to understand what the routines are and how things function.
Knowledge of the fundementals of image processing are needed.  However,
the model that Cantata represents, facilitates the interaction between
the user and the software tools.  Think of it as taking the concepts
of map algebra and putting a graphical front end on it.

> I think it would be more appropriate to ask what application
> area you are talking about before asking what is the
> appropriate GIS interface.

I disagree.  The appropriate GIS interface is one that facilitates
the building of applications.  Early GIS systems got along fine with
a script or macro language.  As GIS system capabilities expand even
sophisticated users start looking for a better way.  Any old Graphical
User Interface is NOT a better way.  Breaking GIS capabilities into
modular functions, facilitating the means for users to connect, customize
and build new functions seems to me a much better way.  An application
is just a certain order of modular functions.

Tim                      (opinions are my own)


		"Without Geography, where would you be?"
			-- Andy Back

Tim McGrath		U.S. Geological Survey
Geographer		Water Resources Division
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