HDTenEightyP/NetNews huggingface dataset:
From: watson@maths.uwa.oz.au (David Watson)
Subject: Re: Angle between two coordinate locations
Organization: University of Western Australia
Date: Wed, 22 Jul 1992 23:41:46 GMT


>>I have a problem where I need to obtain the angle between two points
>>on the screen.  For instance:

>>        +------------------------------------------+
>>        |   * <-point 1                            |
>>        |                                          |
>>        |                                          |
>>        |                                          |
>>        |                                          |
>>        |                                          |
>>        |                                          |
>>        |                   * <-point 2            |
>>        |                                          |
>>        +------------------------------------------+

>>I would expect the function to return the angle as being 135 degrees
>>( or should if my picture was accurate )  Any help would be greatly
>>appreciated.  Thanks

>I'm a little confused, How do you define an angle between two points without
>first defining the location of the vertex.  Is the vertex just assumed to be
>the origin (0,0)?
>Edward M.Starczewski       email: stare@lonex.rl.af.mil

I wondered about that too, but if it were (0,0) the angle returned
would be less than 135 degrees.
Give us a clue, Randi

--
Dave Watson                           Internet: watson@maths.uwa.oz.au
Department of Mathematics            
The University of Western Australia               Tel: (61 9) 380 3359
Nedlands, WA 6009  Australia.                     FAX: (61 9) 380 1028
From: rpatil@nmsu.edu (Raj Patil)
Newsgroups: comp.graphics
Subject: Object labelling Algorithms....
Date: 27 Jul 92 20:36:59 GMT
Distribution: comp.graphics
Organization: Computing Research Lab

Hi: 

Has anyone implemented following features extraction routines?.
These features are mentioned in Pratt's Image processing book on page 646.
He has a reference to this which is unpublished Stanford Research Institute'
Notes. Has anyone implemented these or know of any place I can get hold 
of routines which can do following things.


1) The smallest rectangle oriented along the major axis of 
   the object that encompasses the object (Object oriented bounding box)
                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
2) dimensions of object oriented box, width, height

3) the minimum and maximum distance between the centroid and a 
   perimeter pixel

4) The angle of the minimum and maximum radius vector with respect 
  to the horizontal axis

5) ratio of min radius angle to max radius angle.


Regards

raj
USDA, ARS
Newsgroups: comp.graphics
From: justine@tsd.arlut.utexas.edu (Justine Blackmore)
Subject: 3-d objects in terms of polygons?
Organization: Applied Research Labs, University of Texas at Austin
Distribution: comp
Date: Wed, 29 Jul 1992 19:47:56 GMT


Does anyone know of a simple (preferrably cheap) package out there that 
will run on Sun platforms, and will allow us to create, view and manipulate 
3-d objects as collections of closed polygons?

To produce data for one of our projects, we need to be able to
interactively create, edit and manipulate various 3-d objects, and
guarantee that the result is always described solely in terms of the object's
polygon faces (e.g., guarantee there no stray lines in the object's file
description, etc). But unfortunately, none of the free packages that we
have gotten ahold of has this capability built in.

Any help is greatly appreciated,

please send e-mail: justine@titan.tsd.arlut.utexas.edu

Justine Blackmore
Applied Research Labs
University of Texas at Austin
justine@titan.tsd.arlut.utexas.edu
From: jamie@tasman.rocky (Jamie Thompson)
Newsgroups: comp.graphics
Subject: Re: Siggraph receptions
Date: 22 Jul 92 23:19:17 GMT
Reply-To: jamie@tasman.rocky
Distribution: usa
Organization: Sun Microsystems

In article 14h8r3INN7k5@cs.utexas.edu, kelvin@cs.utexas.edu (Kelvin Thompson) writes:
>
>Where are the Courses and Papers/Panels receptions going to be
>at Siggraph this year?
>
Courses' reception Monday night - Navy Pier (buses from hotels and McCormick)
Papers/Panels reception Thurs night - Hyatt, West Tower lobby
Newsgroups: comp.graphics.visualization
From: craven@cg.emr.ca (Jim Craven)
Subject: Arrowhead plotting routine, anybody?
Reply-To: craven@cg.emr.ca
Organization: Dept. of Energy, Mines & Resources, Canada
Date: Tue, 28 Jul 1992 15:12:32 GMT

I ask this questions to avoid re-inventing the wheel.

I am looking for a subroutine that given the head and tail
positions of a vector will calculate positions to
move to in order to draw an arrow head.   Has anybody
done this before?

Jim
---
We shall not cease from exploration and |Jim Craven (craven@cg.emr.ca)
the end of all our exploring will be to |Seismology & Electromagnetism
arrive where we started and know the    |Geological Survey of Canada
place for the first time.  T.S. Eliot   |Ottawa Canada K1A 0Y3
From: henrik@mpci.llnl.gov (Henrik Klagges)
Newsgroups: comp.graphics.visualization
Subject: Re: Neural Networks and HyperPlanes
Date: 21 Jul 92 17:14:13 GMT

mskuhn@immd4.informatik.uni-erlangen.de (Markus Kuhn) writes:

>Representing 3-d hyperplanes in a 4-d space is still quite easy: Make
>an 3-d animation with moving points and hyperplanes. Time is the fourth
>dimension, i.e. a hyperplane is

>          ax + by + cz + dt + e = 0

The problem here is that time is usually already needed to visualize the
learning progress. 

Cheers, Henrik

massively parallel group at Lawrence Livermore
IBM Research physics group Munich

--

Cheers, Henrik
MPCI at LLNL
IBM Research
From: n8949793@henson.cc.wwu.edu (Ichen Lee)
Newsgroups: comp.graphics.visualization
Subject: CAD drawing package
Date: 26 Jul 92 22:45:12 GMT
Article-I.D.: henson.1992Jul26.224512.21816
Organization: Western Washington University



I am looking for a CAD drawing package to deal with an image database has been
written in C.

In this database, we stored the objects as 2D polygons.   In the data file,
it sepcified one line by two points.   This database only stored engineering
drawings and has been done on an Unix workstation.

Does anyone know somewhere in the public domain that can be FTP'd for free?


Thanks in advance.


Please send mail : n8949793@henson.wwu.edu   



-Ichen  
Newsgroups: comp.graphics.visualization
From: mskuhn@immd4.informatik.uni-erlangen.de (Markus Kuhn)
Subject: Re: Neural Networks and HyperPlanes
Organization: CSD., University of Erlangen, Germany
Date: Tue, 21 Jul 1992 07:33:15 GMT

vachha@cisa.cis.uab.edu (Rustom (Yuppy) Vachha) writes:

>This implementation currently restricts visualization of
>networks with only 2 input nodes. If we have three input nodes, the
>hyperplanes will be PLANES and with 4 input nodes, ??? .

>HENCE WE NEED TO DEFINE A STRATEGY TO CONVERT N-dimensional DATA INTO 2 D.
>  How do we represent N dim hyperplanes?

Representing 3-d hyperplanes in a 4-d space is still quite easy: Make
an 3-d animation with moving points and hyperplanes. Time is the fourth
dimension, i.e. a hyperplane is

          ax + by + cz + dt + e = 0

You get another few dimensions by using colors, but then the person
looking at the images has to be quite experienced.

Have fun ...

Markus

-- 
Markus Kuhn, Computer Science student -=-=- University of Erlangen, Germany
Internet: mskuhn@immd4.informatik.uni-erlangen.de  |  X.500 entry available
------------------ ISO?  Nicht immer. Aber immer fter! -------------------
From: johne@iti.gov.sg (Dr. John S. Eickemeyer)
Newsgroups: comp.graphics.visualization
Subject: Representing hyperplanes ((N-1)-flats in N-space) in 2D (was Re: Neural Networks and HyperPlanes)
Date: 22 Jul 92 03:31:01 GMT
Organization: Information Technology Institute, National Computer Board, Singapore.

In article <1992Jul20.173438.12081@cis.uab.edu> vachha@cisa.cis.uab.edu (Rustom (Yuppy) Vachha) writes:
>HENCE WE NEED TO DEFINE A STRATEGY TO CONVERT N-dimensional DATA INTO 2 D.
>  How do we represent N dim hyperplanes?

Parallel Coordinates has a better chance of doing the job than any other
methods I am aware of.  I am not sure if they have been used to display 
regions of hyperspace per se, but they do well for visualization of
hyperplanes ((N-1)-flats) as well as points (0-flats) and (N-2)-flats which
are contained in them.  Try Inselberg's papers to get started, and the first
several chapters of my dissertation.  A recently posted bibliography is 
attached below.

All the best,

- John :)

------------------------ cut here ----------------------------------------------

>From johne Thu Jun 25 09:14:10 SST 1992
Article: 383 of comp.graphics.visualization
Newsgroups: comp.graphics.visualization
From: johne@iti.gov.sg (Dr. John S. Eickemeyer)
Subject: Re: References on representing N Dim data
Keywords: Parallel Coordinates, Multidimensional Visualization
Organization: Information Technology Institute, National Computer Board, Singapore.
Date: Thu, 25 Jun 1992 01:12:13 GMT

And of course, no reference list about representing multidimensional data 
would be complete without Parallel Coordinates... :)  If you need a general 
method that can represent multivariate relationships in N dimensions, I 
would recommend taking a good look at Parallel Coordinates.  The papers by 
Inselberg are the best place to start...

\bibitem[Cho87]{Cho87} T. Chomut (1987), {\bf Exploratory Data
Analysis Using Parallel Coordinates}, M. Sc. Thesis, UCLA Computer
Science Dept., IBM LA Sc. Cen. Rep. 1987-2811.

\bibitem[DW91]{DW91} A. Desai, L. C. Walters (1991), {\it Graphical
Presentations of Data Envelopment Analyses: Management Implications from
Parallel Axes Representations\/}, Decision Sciences Journal,
{\bf 22-2:} 335-353. 

\bibitem[Eic91i]{Eic91i} J. S. Eickemeyer (1991), {\bf Visualizing 
\(p\)-Flats in \(N\)-Space Using Parallel Coordinates}, PhD. Thesis, 
UCLA Computer Science Dept.

\bibitem[Eic91ii]{Eic91ii} J. S. Eickemeyer (1991), {\bf A New Approach 
to Multidimensional Visualization Using Parallel Coordinates}, IT Works
`91 Conference Proceedings (Singapore), 79-90.

\bibitem[GDCM90]{GDCM90} C. Gennings, K. S. Dawson, W. H. Carter, R. H.
Myers (1990), {\it Interpreting Plots of a Multidimensional Dose-Response
Surface in a Parallel Coordinate System\/}, Biometrics
{\bf 46:} 719-735. 

\bibitem[ID87]{ID87} A. Inselberg, B. Dimsdale (1987), {\it
Parallel Coordinates For Visualizing Multi-Dimensional
Geometry\/}, in {\bf Proceedings of Computer Graphics International
'87} (T. L. Kunii, ed.), Springer-Verlag, Toyko.

\bibitem[ID90]{ID90} A. Inselberg, B. Dimsdale (1990), {\it
Parallel Coordinates: A Tool For Visualizing Multi-Dimensional
Geometry\/}, Proc. IEEE Conf. Visualization '90, 361-378.

\bibitem[IRC87]{IRC87} A. Inselberg, M. Reif \& T. Chomut (1987), {\it
Convexity Algorithms in Parallel Coordinates\/}, Journal of the ACM {\bf
34:} 765-801.

\bibitem[Ins85]{Ins85} A. Inselberg (1985), {\it The Plane with
Parallel Coordinates\/}, Special Issue on {\it Computational
Geometry\/}, The Visual Computer {\bf 1:} 69-91.

\bibitem[Weg90]{Weg90} E. Wegman (1990), {\bf Hyperdimensional Data
Analysis Using Parallel Coordinates}, J. Amer. Stat. Assoc. {\bf 85:}
664-675. 

- John :)


--------------------------------------------------------------------------------
Dr. John S. Eickemeyer                                          johne@iti.gov.sg
Member of Technical Staff                                          (65) 772-0406
Information Technology Institute     "He will never fail you nor forsake you..."
Singapore 0511                                                       - Deut 31:8
--------------------------------------------------------------------------------
Newsgroups: comp.graphics.visualization
From: andyrose@netcom.com (San Francisco Fractal Factory)
Subject: Three cheers for Computer Graphics World
Date: Tue, 21 Jul 92 17:33:56 GMT
Organization: Netcom - Online Communication Services  (408 241-9760 guest) 

CGW, July 1992 spine says: Scientific Visualization and has a nice cover
from John (the greatest computer animator alive) Grower of Santa Barbara
Studios.  2K image of some isosurfaces and 3D model of shuttle and
some nice wood texture and star field.

John GantzVP, chief analyst Dataquest (Framingham, MA) provides us with a
very stylish 2D graph (with red to orange color grade background) indicating

475,000 R&D scientists and programmers using SCI/VIS tools
and that 10% of them are heavy users.

He predicts that 1996 will have 545,000 R&D scientists using SV tools and that
17% of them will be heavy users.

This data is applicable to "aerospace 
and automotive manufacturing, oil and gas, and engineering services"

Mr Gantz alludes to "government statistics."

--
I know it is easy to crow about statistics and such but what exactly is a
"heavy user"?  If you are reading this you are a heavy user (maybe), and
are there 47,500 of us around?  Are there 475,000 machines capable of (lets
say some kind of 3D isosurface in a resaonable amount of time)?  

My real beef is the expected 16% growth crap.  Figuring a 3130 which listed for
a zillion bucks yesterday has the resell value of a used 
toothbrush now, and the
RAPID PROLIFERATION of low-cost high speed workstations (read Intel P5), I 
figure  a lot of people are going to 'do visualization' before 1996 who
don't 'do it' now.

<Heavy users unite! Do visualization together.>

Arielle Emmett, freelance writer of Media, Penna gives a nice overview of
SV, mentioning apE and AVS, IBM/SGI Explorer, and Wavefront stuff.  She focuses
on the interface between the computer and the scientist being the chief area
of research these days rather than strictly graphics or database isues.  She
gives good space to connectivity regarding all these disparate systems.

"Dr. Stephen Franklin, director of advanced scientific computing (heavy?)
at UC Irvine likens the toolkit revolution to a new generation of
scientific spreadsheets.  ...  One thing is certain says Franklin,
"The new toolkits make life much easier for us.  Whether they'll
make it all the way into the casual-user basis, something like
Lotus 1-2-3, is hard to predict.""


AnR



-- 

Andrew Rose
andyrose@netcom.com
FAX 4155537756
From: hollasch@kpc.com (Steve Hollasch)
Newsgroups: comp.graphics.visualization
Subject: Re: Representing hyperplanes ((N-1)-flats in N-space) in 2D (was Re: Neural Networks and HyperPlanes)
Summary: Representation via successive projections
Date: 22 Jul 92 18:37:09 GMT
Organization: Kubota Pacific Computer, Inc.

vachha@cisa.cis.uab.edu (Rustom (Yuppy) Vachha) writes:
> Hence we need to define a strategy to convert N-dimensional data into 2D.
> How do we represent N dim hyperplanes?

    My thesis on this topic used two approaches.  The raytracing approach
fires rays through a 3D grid and yields a 3D image (3D RGB field); I don't
think this is what you're looking for.

    The other approach was for a wireframe viewer.  This is not a new
technique, and basically involves successive projections, e.g. 4D -> 3D,
and then 3D -> 2D.  While you _can_ bundle these projection mathematically
to 4D -> 2D, the successive nature of the projections allows you to tailor
parameters for each projection.  For example, you can use parallel
projection for 4D -> 3D, and then perspective projection for 3D -> 2D.  Or
parallel/parallel, perspective/perspective, or perspective/parallel.  In
addition, you can also mess with viewing angles and the like.

    This is rather trivial for transforming points, and so is each for
wireframe data.  However, visualization of 4D wireframes is very limited
in its usefulness.  Other approaches have used a scanline (scanplane?)
approach, but my impression is that this approach would be very complex.

    With respect to tiling 4D functional fields, I have thought about how
you'd tesselate the hyperplane and then view it, but didn't get very far
in implementing it.  I think that this approach might be more confusing
than a 3D RGB field.

_____________________________________________________________________________
Steve Hollasch                                  Kubota Pacific Computer, Inc.
hollasch@kpc.com                                Santa Clara, California
From: unilrh@uts.uni-c.dk (Leif R|dgaard)
Newsgroups: comp.graphics.visualization
Subject: handling multi-picture-formats as tiff (add/remove/extract picture)
Date: 20 Jul 92 17:18:11 GMT
Distribution: comp.graphics.visualization
Organization: UNI-C, Danish Computing Centre for Research and Education

We are offen dealing with multi-picture-files such as tiff and hdf,
where we either can make 1 file with many pictures or many files with each
one picture. More image-packages such as pbmplus, "san diego image tools"
can handle tiff-pictures, but i havn't seen (noticed) any utilities to pack
and unpack pictures into multi-picture-files. Utilities to add a picture
to a multi-picture-file, to extract a single picture from multi-picture-files,
to remove a picture from a multi-picture-file would be nice to have.

Can anybody tell me where to find such utilities especialy tiff ones.
-- 
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+    Leif R|dgaard Hansen                                               +
+    UNI-C Lyngby, Danish Computing Center for Research and Education.  +
+    DTH, building 305, DK 2800 Lyngby                                  +
+    Phone: +45-45.93.83.55                                             +
+    Fax:   +45-45.93.02.20                                             +
+                                                                       +
+    E-Mail: unilrh@unisgi.uni-c.dk                                     +
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
From: rpatil@nmsu.edu (Raj Patil)
Newsgroups: comp.graphics.visualization
Subject: Object Recognition algorithms
Date: 27 Jul 92 20:44:08 GMT
Distribution: comp.graphics.visualization
Organization: Computing Research Lab


Hi: 

Has anyone implemented following features extraction routines?.
These features are mentioned in Pratt's Image processing book on page 646.
He has a reference to this which is unpublished Stanford Research Institute'
Notes. Has anyone implemented these or know of any place I can get hold 
of routines which can do following things.


1) The smallest rectangle oriented along the major axis of 
   the object that encompasses the object (Object oriented bounding box)
                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
2) dimensions of object oriented box, width, height

3) the minimum and maximum distance between the centroid and a 
   perimeter pixel

4) The angle of the minimum and maximum radius vector with respect 
  to the horizontal axis

5) ratio of min radius angle to max radius angle.

raj
USDA, ARS
From: jek@duke.cs.duke.edu (James E. Kittock)
Newsgroups: comp.graphics.visualization
Subject: Inventor?
Date: 28 Jul 92 19:28:20 GMT
Organization: Duke University Computer Science Dept.; Durham, N.C.


Could someone please tell me about Inventor?  Anything would be
useful, including where to look for more information.  Thanks.

-- 
James Kittock   --   Duke class of 1992    --    Computer Science/Mathematics 
jek@cs.duke.edu | mcnc!duke!jek | PO Box 5750, Duke Station, Durham, NC 27706
"Yes, I will kiss the girl from Venus for science." - They Might be Giants
From: ward@zoyd.ae.utexas.edu ((Steven) Ward)
Newsgroups: comp.graphics.visualization
Subject: Tech. Papers
Date: 26 Jul 92 15:09:43 GMT
Distribution: comp.graphics.visualizations,comp.graphics
Organization: CFD Lab, Dept ASE-EM, University of Texas at Austin


I'm an outsider to the hardcore comp.graphics field, but make use of
some of the techniques in my CFD research.  I have some articles I would
like to get into print but have no idea which journals are around
for technical stuff.  Could some kind soul please email some points
of contact for publications, journals, etc?  


Thanks

Steve Ward
ward@cfdlab.ae.utexas.edu

p.s.  Does *_ANYONE_* out there use IBM's graPHIGS with FORTRAN?
Newsgroups: comp.graphics.visualization
From: hahn@seas.gwu.edu (James K. Hahn)
Subject: Fellowship at the George Washington University
Organization: George Washington University
Date: Wed, 22 Jul 1992 20:31:26 GMT



Due to the responses to the first posting, I am including more
information.


********************************************************************
We are announcing a fellowship at the George Washington University
in computer graphics. The fellowship should begin either Fall '92
or Spring '93 and is for Ph. D. students.

The Presidential Merit Fellowship at GWU is the most prestigious fellowship
at GW. The fellowship is for three years. The stipend is approximately
$15,000 per year. Full tuition is provided. After the three years, the 
student is expected to be supported through regular project grants.

The Computer Graphics and Animation Group at the George Washington University
has recently established a laboratory in a new building and is actively 
engaged in a number of research areas. These include:

	Computer Animation
	Scientific Visualization
       	Realistic Image Synthesis
       	Virtual Reality
       	Sound Synthesis/Synchronization for Animation and VR
	User Interfaces

If you are interested in the kind of work we are currently conducting, we
have entries in the Film and Video Show, the Video Screening Room, and
a paper in the Proceedings in this year's SIGGRAPH.

We recently purchased three Indigo Elans and a Crimson Elan from SGI.
The lab is also equipped with an IRIS 4D/210GTX, six Sun 4 workstations
and their file server, and full animation video equipment including an 
editing suite.
We also have access to a number of HP and Sun workstations including two
HP 835 Turbo SRX.

The group is currently composed of three faculty members:
James Hahn, John Sibert, and Hikmet Senay
as well as approximately 15 graduate students.

If you are interested in more information, please contact me
by email:

hahn@seas.gwu.edu
(202) 994-5920

Send me your vita, full transcript of your undergraduate and
graduate courses, any papers or thesis you might have written,
and a description of your interest to:

Prof. James Hahn
Department of Electrical Engineering and Computer Science
The George Washington University
801 22nd Street NW
Washington, DC 20052
-- 
James K. Hahn		The George Washington University
Asst. Professor		Department of EE&CS
hahn@seas.gwu.edu	801  22nd Street NW, Washington, DC  20052
Newsgroups: comp.graphics.visualization,comp.graphics
From: rtipnis@maxine.wpi.edu (Rajeev Tipnis)
Subject: SIGGRAPH anonymous ftp site
Organization: Worcester Polytechnic Institute
X-Newsreader: Tin 1.1 PL4
Date: Tue, 21 Jul 1992 21:30:46 GMT


In SIGGRAPH'92 Advance Program booklet, it is mentioned that the
unix node : siggraph.org (128.248.245.250) is an anonymous
ftp site and the dir : /info/s92/courses contain in depth course
material. However, I was not able to connect to this site.

Is there anyone out there, who could connect to this site ?

Thanks.


-- Rajeev