HDTenEightyP/NetNews huggingface dataset:
From: rjbolger@vax1.tcd.ie
Subject: Re: 24bit > 8bit Display Question
Organization: Trinity College Dublin
Date: Fri, 14 Aug 1992 11:58:42 GMT

In article <BssDHt.19u@news.cso.uiuc.edu>, pgrg9345@uxa.cso.uiuc.edu (pAul rAdja ) writes:
> Question:  I need to be able to display a 24bit image on a 
> pc that only has an 8bit look-up table. Does anyone know of a
> good way or reference on how to optimally fill the
> table up? Speed is a strong consideration in my problem.

For a quick way of displaying 24 bit images on a 256 color display
with good quality, you can tradeoff screen resolution for extra
depth.

First generate a palette of three colour ramps of r,g & b, with g & b 
going from 0 to 63 in intensity and r going from 0 to 31. Then plot
each image pixel using four screen pixels as such:
		 	_____________________
		       |	 |	     |
		       | Red     |     Green |
		       |---------------------|
		       |	 |	     |
		       | Blue	 |     Red   |
		       |---------------------|

This works surprisingly well giving a '17' bit display but only at
resolutions greater than 320x200.  I'm lucky enough to have a 1MB 
Trident card that gives 1024x768 resoloution, and using this technique
I get an apparent res of 512x384 which is good enough for my needs.

You can try other combinations such as three screen pixels per image
element, but this introduces artifacts in the image.  Using Red twice
and halving its intensity was the best combination that I could find.

The drawback with this method is that the image is displayed at a low
intensity because only 1/3 of the screen guns are switched on, but the
overall quality is really quite good.

Hope this helps, but if you need any more info contact me through E-mail.

Regards,
			 * Richard Bolger         *
Richard.		 * Trinity College Dublin *
			 * Rjbolger@vax1.tcd.ie   *
Newsgroups: comp.graphics
Subject: Mac Quicktime images
From: pdbourke@ccu1.aukuni.ac.nz (Paul David Bourke)
Date: Mon, 17 Aug 1992 23:15:18 GMT
Organization: University of Auckland, New Zealand.
Keywords: Mac Quicktime images
Summary: Mac Quicktime images

A number of Architectural (Macintosh) JPEG compressed images are available
from wuarchive.wustl.edu in the mirrors/architec directory (new images should
be there very soon)

These images are samples of student projects done at the School of Architecture
Auckland University. Students are available for commercial projects using a 
wide variety of computer hardware and application sofwtare. For more details
contact us below.

P.D.Bourke
Architecture School     Fax:   +64 -9 3737410 
Auckland University     Ph:    +64 -9 3737999 x7367
Private Bah 92019       Email: pdbourke@ccu1.aukuni.ac.nz
Auckland
New Zealand
From: galanter@nyu.edu (Philip Galanter)
Newsgroups: comp.graphics
Subject: SigGraph, Chicago, and Unions
Date: 14 Aug 92 01:55:00 GMT
Reply-To: galanter@nyu.edu (Philip Galanter)
Organization: New York University


Both at SigGraph and now here I have heard/read a number of anti-union  
slams.  Yes, Chicago is a union town...it is also a town where working  
class people have a chance to earn a decent living and maybe, if they are  
careful and frugal, buy a home for their family someday.  

Its time to stop laying the blame for a poor US economy at the feet of the  
people who have the least power to influence the direction their given  
industry takes, and are the first to suffer when things go bad.  After 12  
years of Reagan/Bush/"right-to-work" union busting the economy is in worse  
shape than ever, save for the few at the very top who enjoy the largest  
gap between the executive and working class in the West.

Yes, unions are _sometimes_ corrupt, wasteful, and/or counter-productive.
So are the government, banks, Fortune 500 companies, and computer industry  
standards committees.  Please allow working class people the only leverage  
over their economic future that they have.  At the end of the day they are  
just like you, tired and a little bit older...

Phil

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Philip Galanter         New York University    phone:    212-998-3041
Research Associate      251 Mercer             fax:      212-995-4120
Academic Computing      New York, NY 10012     internet: galanter@nyu.edu
 
   O f f i c e   o f   A r t s   &   M e d i a   T e c h n o l o g i e s
Newsgroups: comp.graphics
Subject: BILL GATES Gif
From: T.D.Sadlier@massey.ac.nz (T.D. Sadlier)
Date: Tue, 18 Aug 92 21:02:10 GMT
Organization: Massey University, Palmerston North, New Zealand
X-Reader: NETNEWS/PC Version 2c

Can the person who kindly sent me the BILL GATES Gif please re-send
it to me - It has vanished!!  Must have deleted it by mistake -
sorry!!

Tanya Sadlier
Organization: Queen's University at Kingston
Date: Saturday, 22 Aug 1992 13:52:00 EDT
From: <JIANGY@QUCDN.QueensU.CA>
Newsgroups: comp.graphics.visualization
Subject: Re: Help: Surfaces from contours


I need the code too if possible. Please post to this group.

Thanks a lot.


Dennis Jiang
Queen's U.
Newsgroups: comp.graphics.visualization
From: little@sei.cmu.edu (Reed Little)
Subject: ray tracer wanted
Organization: The Software Engineering Institute
Date: Mon, 17 Aug 1992 15:19:42 GMT


i`m new the the visualization area.  i`m looking for a ray tracer that will
take as input a 3d block of data (an mri scan) and produce a display for
x windows.  please send me e-mail as i do not read this group.  thanks.


========================================================================
	reed little
	software engineering institute - carnegie mellon university
	little@sei.cmu.edu, +1.412.268.5792
From: erich@dehn.mth.pdx.edu (Erich Boleyn)
Newsgroups: comp.graphics.visualization
Subject: Re: Automated display of graphs
Date: 12 Aug 92 17:10:13 GMT
Article-I.D.: dehn.erich.713639413

davids@eng.auburn.edu (David Schreibman) writes:


>  I am looking for references or any other information about automated graph
>generation.  Are there any widely available tools for this?  Thanks in advance
>to anyone who can help.

   Are you interested in automated "graph generation" or automated "graph
display".  They are very different topics.  Generation is fairly easy given
the kind of constraints that you're interested in.  Display is another
ballgame entirely.

   Erich

--
             "I haven't lost my mind; I know exactly where it is."
    / --  Erich Stefan Boleyn  -- \       --=> *Mad Genius wanna-be* <=--
   { Honorary Grad. Student (Math) } Internet E-mail: <erich@dehn.mth.pdx.edu>
    \  Portland State University  /      WARNING: INTERESTED AND EXCITABLE
Newsgroups: comp.graphics.visualization
From: asimov@wk223.nas.nasa.gov (Daniel A. Asimov)
Subject: Re: Rotation in nD space
Organization: NAS, NASA Ames Research Center, Moffett Field, CA
Date: Wed, 19 Aug 92 19:06:26 GMT

In article <1992Aug19.100559.13778@fwi.uva.nl> wijkstra@fwi.uva.nl (Marcel Wijkstra (AIO)) writes:
	[...]
>The question is: how do I 'rotate' an object in 4D? Or even: what is
>rotation in 4D? 
	[...]
>(1) WHAT IS 'ROTATION' IN ND SPACE EXACLY (IF IT IS POSSIBLE AT ALL)?
>    This question comes merely from the difficulties I have in abstract
>    thinking, i.e. I haven't got the slightest idea what an object in
>    nD space would 'look' like.
	[...]
> Marcel Wijkstra

As in lower dimensions, the mathematical definition of a rotation in
any Euclidean space R^n is any transformation that takes 0 to 0 and
preserves all distances.  Oh, and one more condition: the transformation
must preserve orientation as well.  (This insures that there is a continuous
family of rotations connecting any one of them to the identity.)

In terms of matrices, rotations are given by orthogonal matrices with
positive determinant.  (An orthogonal matrix in mathematics is one whose
transpose is its inverse.)

EVEN DIMENSIONAL CASE:
It can be shown with linear algebra that, in fact, given a rotation
S of an even-dimensional Euclidean space R^2n, there are n mutually
orthogonal 2-dimensional subspaces P(1),...,P(n) and angles
theta(1),...,theta(n) such that for each i = 1,...,n the transformation 
S is just an ordinary rotation by angle theta(i) when restricted to 
the plane P(i).

ODD DIMENSIONAL CASE:
If the dimension is odd, then a rotation S on R^(2n+1) must leave some
1-dimensional subspace L fixed, and the restriction of S to the 
orthogonal complement of L is covered by the even-dimensional case above.


--Dan Asimov
asimov@nas.nasa.gov

Mail Stop T045-1
NASA Ames Research Center
Moffett Field, CA 94035-1000
(415) 604-4799
Newsgroups: comp.graphics.visualization,comp.graphics,comp.windows.x.motif
From: smd@sl0091.srl.ford.com (Steve Dahmen)
Subject: Changing controlling stereo real estate (possible?)
Followup-To: comp.graphics.visualization
Originator: news@pms001
Organization: Scientific Research Lab, Ford Motor Company
Date: Thu, 13 Aug 1992 15:50:06 GMT


Dear People Knowledgeable in Stereo Tech,

We here at Ford are just getting into stereo vision technology, having procured a number of sets of stereoGraphics goggles & controllers for use on an
application which must run on SGI's and IBM RS/6000s.

To now, we've only seen stereo stuff that takes over the WHOLE screen.
We'd like to just open a Motif window, tho, and have just that be in stereo, with the rest of the screen viewable through the stereo goggles.
It seems that other real estate is all messed up when the monitor is in
stereo mode.  As anyone had success with *limiting* the stereo effect to a
given window?  A a co-worker believes he saw it on a video he bought at SIGGRAPH '92.

Sadly, we found few answers at SIGGRAPH.  Even the guys at the StereoGrphics booth at SIGGRAPH (and he was up there in the corp) knew not where to turn.

Any names or info would be appreciated.  Send email and I'll summarize.



-- 
Steve Dahmen ** Graphics Application Programmer
Ford Motor Company
smd@sl0091.srl.ford.com
313-248-2418 (work)
-- 
Steve Dahmen ** Graphics Application Programmer
Ford Motor Company
smd@sl0091.srl.ford.com
313-248-2418 (work)
From: rcs91900@zach.fit.edu ( Charles Stockman /ADVISOR-Clutterham)
Newsgroups: comp.graphics.visualization
Subject: Is anyone using ARCINFO (Map Making Software)
Date: 20 Aug 92 12:19:36 GMT
Organization: Florida Institute of Technology, Melbourne USA

Is there a user's group using ARCINFO

or 

anyone using it individually 

that is interested in sharing information

Please send address and name and phone number
From: stryker@pencom.com
Newsgroups: comp.graphics.visualization
Subject: Mass storage for graphics systems
Date: 19 Aug 92 14:49:39 GMT
Reply-To: stryker@pencom.com
Distribution: usa
Organization: Pencom Software


Is anyone using RAID disk arrays to facilitate operations in this field?
From: wijkstra@fwi.uva.nl (Marcel Wijkstra (AIO))
Newsgroups: comp.graphics.visualization
Subject: Rotation in nD space
Date: 19 Aug 92 10:05:59 GMT
Organization: FWI, University of Amsterdam

In 3D, you can rotate an object by applying a 3x3 transformation
matrix to all points. Rotation around the X axis over angle A
requires the matrix:
		1  0  0     
		0  C  S		where C = cos(A)
		0 -S  C		  and S = sin(A)

Note: since I do not need translations, I do not need a 4x4 matrix and
homogenous coordinates.

I am trying to visualize objects in a higher space, e.g. a hypercube
in 4D. To do so, I discard the fourth coordinate and treat it as a
regular 3D object, i.e. use perspective projection to get it on the
screen. A non-rotated hypercube thus results in a boring picture of
a plain cube. Things get more interesting if the hypercube is rotated
in 4D space. Then you would probably see something like two disformed
cubes inside eachother, with their corners connected.

The question is: how do I 'rotate' an object in 4D? Or even: what is
rotation in 4D? I proved (I think) that true rotation of a 4D object
around one of the four principal axes is impossible. In other words:
there exists no matrix M:

		1 0 0 0
		0 a b c
		0 d e f
		0 g h i
	
that rotates a point (xyzt) around the X axis over a certain angle A,
such that applying MM is the same as rotating over 2A. Note: such an
M could exist, if you use complex numbers, but I doubt if that is
allowed.

The only thing I could come up with, is to use three matrices

	1  0  0  0		1  0  0  0		1  0  0  0
	0  C  S  0	,	0  S  0  C	and	0  1  0  0
	0 -S  C  0		0  0  1  0		0  0  C  S
	0  0  0  1		0  C  0 -S		0  0 -S  C

for rotations around the XT, XZ and XY plane. Extended to an nD space,
this approach results in (n^2 + n)/2 different rotation (n-2 D) spaces.

My final questions are:

(1) WHAT IS 'ROTATION' IN ND SPACE EXACLY (IF IT IS POSSIBLE AT ALL)?
    This question comes merely from the difficulties I have in abstract
    thinking, i.e. I haven't got the slightest idea what an object in
    nD space would 'look' like.

(2) IS THE ABOVE APPROACH FOR ROTATIONS IN 4D SPACE CORRECT?
    If so, then rotation of a left shoe (being a 3D object, i.e. with
    t=0 for all points) can result in...a right shoe.

(3) ARE THERE ANY OTHER COMMENTS ON THE STATEMENTS I MADE?
    Please, ALL comments/information/flames (yes, even flames) are very
    welcome.

Thanks for reading,
Marcel.
-- 
 X	   Marcel Wijkstra   AIO   (wijkstra@fwi.uva.nl)
|X|	     Faculty of Mathematics and Computer Science	
 X	       University of Amsterdam   The Netherlands
======Life stinks. Fortunately, I've got a cold.========
Newsgroups: comp.graphics.visualization
From: makrisna@convex1.tcs.tulane.edu (Krishna Achuta Rao)
Subject: Need help with choosing visualization hardware/software
Nntp-Posting-Host-[nntpd-4694]: convex1.tcs.tulane.edu
Organization: Tulane University, New Orleans, LA
Date: Sat, 22 Aug 1992 01:53:29 GMT

Hi there!


I am in the process of selecting hardware and software for use in visualization
of geophysical data (climate data from various sources including satellite, GED
COADS, GCM output etc). I would like to hear from people who have used various 
systems. My specific questions (after reading the FAQ) are:

     1. What hardware do you use? PC/mac/mainframe/workstation and as many
        specs. as you consider important.
     2. What software do you use? (eg. NCAR graphics) What Operating system
        does it run on? Is it public domain/free? If it is commercial software
        how much does it cost (ballpark figure will do)?
     3. What are your comments on the software you use? What do you feel are
        the strong/weak points of what you use?

I have access to PC's (386 with SVGA), IBM RS6000 (RISC), IBM 3081 (mainframe
with CMS o.s that has NCAR graphics ver. 3.1 and SAS), Convex C120 (unix o.s) 
and they are(can) all (be) connected. So any suggestions on how to utilize 
existing systems will be extremely helpful. Also, any comments on how I can
incorporate a CD ROM into this picture will be useful.

IMPORTANT NOTE: I am a grad student with oh maybe, a couple of thousand 
dollars I could get my advisor to fork out.

Please post or e-mail to makrisna@convex1.tcs.tulane.edu

I will post a summary if there is sufficient interest.

Thanks in advance.
krishna

--
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+ Krishna Achuta Rao, Graduate Student, Mechanical Engg., Tulane University  +
+That's the whole problem with science. You've got a bunch of empiricists    +
+trying to describe things of unimaginable wonder.  -Calvin & Hobbes         +
From: hstroyan@hpfcso.FC.HP.COM (Howard Stroyan)
Date: Thu, 20 Aug 1992 18:20:20 GMT
Subject: Re: Changing controlling stereo real estate (possible?)
Organization: Hewlett-Packard, Fort Collins, CO, USA
Newsgroups: comp.graphics.visualization

In comp.graphics.visualization, checker@acf5.NYU.EDU (checker) writes:

> Anyway, to address the question at hand: I'm no X windows expert, so I'm
> not sure how you'd pull this off, but the solution is pretty obvious;
> draw the desktop at half the vertical resolution to both the top and
> bottom of the screen.  This way when the frame-rate doubler is running
> you'll see the same desktop with both eyes.  You'd draw all 2d objects
> identically to the top and bottom, and all 3d objects from different
> viewpoints, as usual.

This is correct, but you did overlook one more detail.
Since each half frame (now a complete left or right frame) is stretched
to cover the entire screen, a 2:1 aspect ratio is introduced for each
pixel.  If you just cut the X servers screen res to say 1280x512 and 
then replicate the non-stereo pixels in the upper and lower framebuffer
the image will be distorted.  Sort of like a vistavision movie title on 
TV screen.  To adjust for this, the simplest thing to do is to cut the
effective X server resolution to 640x512 and replicate the pixels by 2
in the horizontal dimension.  This approach was taken by E&S in their
Stereo in a window solution.

An alternate approach is to not half the effective frame resolution but to
instead half the effective video bandwidth.  That is, have left and right
framebuffer of full resolution (say 1280x1024) and display them in 
alternation (either interlaced or complete frames).  This would produce
an effective frame rate of 30 fps on a typical 60Hz display.  The 
benefit of this approach is that a high screen res and a 1:1 aspect ratio
are maintained.  The disadvantage is ... well it reminds me of an other
old movie "My Friend Flicker" :-).  I remember seening this setup on
mac in the 89' SIGGRAPH Textronics booth.  I did have stereo_in_a_window
but it strobed terribly.
--
Howard Stroyan                                         
Hewlett-Packard                                        hstroyan@fc.hp.com
User Interface Technology Division
From: eugene@amelia.nas.nasa.gov (Eugene N. Miya)
Newsgroups: comp.graphics.visualization
Subject: [l/m 8/10/1992] Shell2 -- the outrigger	(2/4) c.g.v.FAQ2
Date: 22 Aug 92 11:45:08 GMT
Reply-To: eugene@amelia.nas.nasa.gov (Eugene N. Miya)
Followup-To: poster
Organization: NAS Program, NASA Ames Research Center, Moffett Field, CA

#Disabled
Archive-name: comp.viz.faq

	"Feed me."  -- Audrey II, the Plant in "The Little Shop of Horrors."

Contents
========

Intro
-----
Netiquette
----------
What is visualization?
----------------------
Systems
-------
Issue/problems
--------------
References
----------
================================

Intro
-----

The quality of this FAQ is directly proportional to the information
mailed by participants (that's you) to the maintainer (me, Amelia).
You don't like it?  Blame the rest of the posters and readers.
I don't have 100% time to maintain this.  We are starting from scratch.
If an address or phone is out of date?  Blame the group.  I'm just a dumb
computer posting as I am told.

The structure of this FAQ is currently a twice monthly post, with two
weekly outriggers pointing to the Long (this) version.  We will see how well
this works (empirical science).

You should not have to see this file all the time.  Don't bother saving it
unless you have a flakey net connection.   Grab the most recent revision
off the net.  The Subject: line is designed to fit within the 24-char limit
of most Killfile systems.  Learn about Killfiles.  If you have something
against FAQ files, the regular expression /.*FAQ$/ will Kill All My Children
and me.  We suggest that you learn how to use news and how news works
before complaining.  See news.annouce.newusers.
This post is like a lighthouse or a fog horn.  Learn how to use it.

This is the outrigger, the main FAQ will be posted next week.
From: laviers@IRO.UMontreal.CA (Cocotte Minute)
Newsgroups: comp.graphics.visualization
Subject: any good papers/books... on automated cartography?
Date: 18 Aug 92 20:40:03 GMT
Organization: Universite de Montreal


Hi there!

        Part of my masters research involves the automatic generation
of level (as in altitude) maps from sampled data.

As I am new to this specific field, I was wondering I someone could be kind
enough to point me in the right direction?

Specifically, I am looking to correctly generate iso-curves of points of same 
"altitude" 
i.e. as in altitude maps: lines of 10',20', 30', etc etc 
All I know Is that this problem is not a trivial one.

More generally, I would appreciate any info on books/articles/scriptures 
containing algorithms pertinent to field of map generation or topology.

advTHANKSance

Sebastien

--
_____________________________________________________________________________
|Sebastien Lavier [Calimero]    | Centre de recherche, Hopital du Sacre-Coeur  
|laviers@iro.umontreal.ca       | "The opinions expressed here are mine and  
|Universite de Montreal, Canada |   should also be yours!"
From: cyberoid@milton.u.washington.edu (Robert Jacobson)
Newsgroups: comp.graphics.visualization
Subject: Has anyone benchmarked 3D modeling software?
Date: 17 Aug 92 20:28:23 GMT
Article-I.D.: u.1992Aug17.202823.18594
Organization: WORLDESIGN, Seattle


If you have or if you know of someone or a journal that has, please
email me with information about how to obtain the results.  Thanks.

Bob Jacobson
cyberoid@u.washington.edu
Newsgroups: comp.graphics.visualization
From: steve@steved.ingr.com (Stephen Dow)
Subject: Re: Changing controlling stereo real estate (possible?)
Reply-To: steve@steved.b17d.ingr.com
Organization: Intergraph Corporation, Huntsville, Alabama
Date: Thu, 13 Aug 1992 20:42:39 GMT

smd@sl0091.srl.ford.com (Steve Dahmen) writes:
> 
> Dear People Knowledgeable in Stereo Tech,
> 
> We here at Ford are just getting into stereo vision technology, having 
> procured a number of sets of stereoGraphics goggles & controllers for use 
> on an application which must run on SGI's and IBM RS/6000s.
> 
> To now, we've only seen stereo stuff that takes over the WHOLE screen.
> We'd like to just open a Motif window, tho, and have just that be in stereo, 
> with the rest of the screen viewable through the stereo goggles.
> It seems that other real estate is all messed up when the monitor is in
> stereo mode.  As anyone had success with *limiting* the stereo effect to a
> given window?  A a co-worker believes he saw it on a video he bought at 
> SIGGRAPH '92.
> 
> Sadly, we found few answers at SIGGRAPH.  Even the guys at the StereoGrphics
> booth at SIGGRAPH (and he was up there in the corp) knew not where to turn.
> 
> Any names or info would be appreciated.  Send email and I'll summarize.
> 
> -- 
> Steve Dahmen ** Graphics Application Programmer
> Ford Motor Company
> smd@sl0091.srl.ford.com
> 313-248-2418 (work)
> -- 

    We here at Intergraph have developed and are selling systems which 
display stereo models in a window or multiple windows, while the window
borders and rest of the screen remain viewable through the stereo 
glasses.  These systems replace traditional stereoplotters used by
photogrammetrists; instead of placing the overlapping pair of 
photographs on stages, the photographs are scanned and brought in
to the workstation to be oriented and then used in map compilation, etc.
The systems can also be used to render CAD designs in stereo.
    Basically the way this works is that in stereo mode the whole
workstation screen is interlaced with odd lines seen by one eye and
even lines the other, but only within the stereo windows are the adjacent
raster lines filled with separate left and right view data.

Stephen Dow, Software Scientist
Imaging Systems
Intergraph Corporation
steve@steved.b17d.ingr.com
205-730-7044
From: Glenn.Farley@f201.n914.z8.rbbs-net.ORG (Glenn Farley)
Newsgroups: comp.graphics.visualization
Subject: Re: CFV: sci.virtual-worlds.apps
Date: 20 Aug 92 17:08:06 GMT

yes



 * Origin: PCUG BBS - San Francisco HST/V.32 415-621-2609 (8:914/201.0)
From: hstroyan@hpfcso.FC.HP.COM (Howard Stroyan)
Newsgroups: comp.graphics.visualization
Subject: Re: StereoGraphics Address Needed
Date: 14 Aug 92 21:09:05 GMT
Article-I.D.: hpfcso.21580002
Organization: Hewlett-Packard, Fort Collins, CO, USA

In comp.graphics.visualization, spec01@solomon.technet.sg (Quak Wan Ling) writes:

> Do anyone
> has the address of the company StereoGraphics Corp. that supply this
> form of hardware ? Any help will be much appreciated.

StereoGraphics Corp.
2171-H E. Francisco Blvd.
San Rafael, CA 94901 USA

Phone: (415) 459-4500
  Fax: (415) 459-3020