HDTenEightyP/NetNews huggingface dataset:
From: frank@whare.cavebbs.gen.nz (Frank van der Hulst)
Newsgroups: comp.graphics
Subject: Re: HELP: .FLI specifics
Keywords: FLI animation
Date: 12 Apr 92 15:28:13 GMT
Organization: Tech-Soft Systems, Wellington NZ

king@presto.ig.com (Edward J. King) writes:

>   I'm looking for specifics on .fli files; file formats,algorithms,specs
> and limitations etc.  I already know of FTP sites that have demos and
> PD viewers so don't waste bandwidth by reposting. However, if there
> exists PD source examples I would appreciate an FTP address.

Get FLILIB.ZIP, in the Simtel archive. It contains Turbo-C (PC-specific)
and Assembler source code for creating and playing .FLI files. If you
want to create .FLIs on a Unix system, a better starting point might be
PVQUAN15.ZIP, which I recently uploaded to Simtel20 and garbo.uwasa.fi.
It contains code based on FLILIB which I ported to Unix (gcc -ansi), as
well as other image processing stuff.

Frank.
Newsgroups: comp.graphics
Subject: Computer sketching
From: pdbourke@ccu1.aukuni.ac.nz (Paul David Bourke)
Date: Wed, 15 Apr 1992 02:34:00 GMT
Organization: University of Auckland, New Zealand.
Keywords: Sketching
Summary: COmputer sketching

Some examples of computer sketching for Architetcural applications can be
FTPed from
   mirrors/architec/Documents
at
   wuarchive.wustl.edu
Please FTP the README file first.
These examples illustrate a project where "perfect" CAD models were 
modified so as to create the appearance of human (designer) sketches.
Files include a brief description, some TIFF images, and some HPGL
files. The HPGL files will give better reults if your plotter supports
pencils and has force control.
The sketches are created by modifying 3D CAD models to simulate the
characteristics of human sketches such as line intersection overshoot,
non straight lines, and variable line force.
Files are compressed with the Macintosh Stuffit program and then passed
through BINHEX.
From: zyda@aquarius.cs.nps.navy.mil (Michael Zyda)
Newsgroups: comp.graphics
Subject: Re: SGI IRIX 4.0
Date: 9 Apr 92 04:09:47 GMT
Article-I.D.: aquarius.4602
Reply-To: zyda@cs.nps.navy.mil (Michael Zyda)
Organization: Naval Postgraduate School, Monterey CA

IRIX 4.0.1: We installed 4.0.1 and MANY things were broken or forgotten
by SGI. The most irritating problem being that SGI "forgot" that people
used things like the Spaceball and the Button/Dials box. Fonts through
the font manager are in significantly different places than they were
in 3.3.2, so many programs have ugly looking interfaces, if they
used the font manager.

We are now up to 4.0.3 and if you were watching comp.sys.sgi today,
you saw that "that's fixed in 4.0.5" was announced today. Most of
our systems run like dog meat (very slow) on 4.0.3 compared to
3.3.2 and we are NOT short on memory on the VGXs where this
slowness is seen.

Yes, there probably is a 4.1 soon, probably to be released before
the SGI Developers' Forum next week...

     mz
.
Newsgroups: comp.graphics
From: baker@elec.uq.oz.au (Rex Baker)
Subject: CGM file interpretation/generation
Organization: Prentice Centre, University of Queensland
Date: Mon, 13 Apr 1992 04:22:30 GMT

I am looking for some helpful information regarding the interpretation
and/or generation of CGM files. I am aware of the ANSI standard
regarding CGM file format, however this does not describe the specific
mechanisms of metafile interpretation or generation. The application
that I require only needs to interpret the information in the CGM
file, NOT display it. If anyone has any helpful remarks they would be
greatly appreciated.
From: grooth@prl.philips.nl (groothuis e)
Newsgroups: comp.graphics
Subject: Re: Targa format specifications
Date: 14 Apr 92 09:27:11 GMT
Organization: Philips Research Laboratories Eindhoven, the Netherlands

In article <1992Apr14.051651.8810@usenet.ins.cwru.edu> as666@cleveland.Freenet.Edu (Jonathan Roy) writes:
>
>Can someone tell me a FTP site I can get the Targa format info from?
>I'm know this is a FAQ, but that FAQ posting has scrolled out of my system's
>backlog of news, so I can't look it up.
>

try: capella.eetech.mcgull.ca
directory: /wuarchive/doc/graphic-formats
files:
 README
 targa.format.Z
 targa.ptr.Z

>Thanks.
>-- 
>  |||  Jonathan Roy (The Ninja) Internet: as666@cleveland.freenet.edu
>  |||  -- BBS: Darkest Realm - (Down for now) - Public UUCP/Usenet --
> / | \ "...make him want to change his name,take him to the cleaners,
> devastate him, wipe him out, humiliate him." -CHESS   GEnie: J.ROY18


 456477696E204772-6F6F746875697320   Edwin Groothuis 
 67726F6F74684070-726C2E7068696C69   grooth@prl.phili
 70732E6E6C207338-3934303530373940   ps.nl s89405079@
 6873652E6E6C0D                      hse.nl.
From: robtow@colour.Eng.Sun.COM (Rob Tow)
Newsgroups: comp.graphics
Subject: Need address for IPI (Image Processing Institute) - want tapes
Keywords: IPI tape Lenna Tiffany images Image Processing Institute address
Date: 16 Apr 92 22:10:18 GMT
Reply-To: robtow@colour.Eng.Sun.COM (Rob Tow)
Organization: Sun Microsystems, Inc.  Mt. View, Ca.
NNTP-Posting-Host: colour.eng.sun.com

In the mid 80s I sent off to an outfit whose name I believe was the "Image
Processing Institute", somewhere in southern California, for a large
suite of test images. These included the imfamous Lenna and Tiffany images -
and quite a few others.

I have lost the address/phone number. Can some kind soul provide me with
this information?

-Rob Tow-
Xref: sparky comp.graphics:5398 alt.binaries.pictures.d:2368 alt.binaries.pictures.misc:4546
From: dragon@angus.mi.org (John Lussmyer)
Newsgroups: comp.graphics,alt.binaries.pictures.d,alt.binaries.pictures.misc
Subject: Re: JPEG viewer for win3.0 and 3.1
Keywords: jpeg
Date: 13 Apr 92 17:09:51 GMT
Organization: North Star BBS

billr@iplmail.orl.mmc.com (Bill Richmond) writes:

> 
> 	Why don't you simply convert the jpg files to gif & then
> view those?

Actually it's much nicer to convert them to TGA and view them with a
board that displays 15 or 24 bits per pixel.  Most JPG have the full
24 bits of info.

-----
John Lussmyer (dragon@angus.mi.org  -or-  dragon%angus@teemc.tmc.mi.org)
North Star BBS, Troy, MI --------------------------------- +1 313 524 9024 ---
Newsgroups: comp.graphics
Subject: Re: help with polygon fill for electron raster lithography
From: <PFENNIG@NDSUVM1.BITNET>
Date: Saturday, 11 Apr 1992 11:14:46 CDT
Organization: North Dakota Higher Education Computer Network


In response to the polygon filling problem...

There is an algorithm in a book entitled COMPUTER GRAPHICS with PASCAL
by Marc Berger which has an algorithm that works reasonably well.  It
is called the "Scan line method".  The edges of the polygon are pre-
processed in order to find the inverse slope and maximum y values.
These "edges" are then inserted into an array of list pointers (one
pointer for each unit of vertical resolution) whose array subscript
is the same as its minimum y value.

The array of pointers is then processed starting with the first element
in the array.  A "master" list is maintained which contains the edge
information for the scan line currently being processed.  The x component
of each edge in this master list is incremented by its inverse slope
edge each time through the processing loop.  This loop also adds
and removes edges as they appear or disapear in the polygon.  The
polygon is actually drawn by traversing this master list, alternately
calling "moveto" and "lineto" with the x value being the minimum
x value for that edge where it intersects the scan line being processed.

That summarizes key parts the algorithm which is described much more
completely in the book.  There are several serious typographical
errors (at least 5 in my copy of the book which I believe is a first
edition).  There is also an a slight problem with horizontal polygon
edges for which a solution is given.  The source code in the book is
missing the key part which links all the pieces together but it is
still possible to figure it out from the narative. These errors and
exclusions might have been made to give a student the "challenge" of
verifying the code first-hand.

It should work for you though.  The line drawing algorithm only needs
to be able to draw horizontal lines, and it doesn't need to "look"
at any pixels to process the polygons.  The code has great potential
for optimization (such as using Bresenham's line algorithm for updating
the x values in the processing loop) but it is relatively fast even on
complex polygons.
Newsgroups: comp.graphics
From: thad@lever.asd.sgi.com (Thad Beier)
Subject: Re: Morphing
Reply-To: thad@sgi.com
Organization: Silicon Graphics
Date: Wed, 15 Apr 1992 00:00:27 GMT

In article <1992Apr14.231553.19854@nas.nasa.gov>, eugene@wilbur.nas.nasa.gov (Eugene N. Miya) writes:
|> Ref: Pending SIGGRAPH 92 proceedings (assuming the paper gets accepted).
|> 
|> --eugene miya, NASA Ames Research Center, eugene@orville.nas.nasa.gov


It got accepted!  Now I just have to make the final version...
-- 
Thad Beier..Silicon Graphics..415)335-1028..thad@sgi.com..C-172A N7770T.....FLY!
From: leech@cs.unc.edu (Jon Leech)
Newsgroups: comp.graphics
Subject: Re: Distributing points on a sphere
Date: 11 Apr 92 07:20:56 GMT
Organization: UNC-Chapel Hill Computer Science

In article <worley.702774341@updike>, worley@updike.sri.com (Steve Worley) writes:
> This question is *ALMOST* answered in the FAQ list: however, the
> answer given there will only tessilate a sphere with a certain subset
> of points, something like 6,12,24,48, etc. No flames that "You should
> look at the FAQ!", though, since you want a solution for arbitrary n.

    The number of faces is {4|8}*4^n, n>=0 (the 4|8 depending on
whether you start with an octahedron or tetrahedron). The number of
vertices comes from V+F=E-2 and the recurrence relation for the
subdivision, which I think gives your choice of (4^n)/2+2 or 4^n+2, a
fairly bizzare distribution (4,6,10,18,34,66,...). But I'm confident
the resulting distribution is not even a local minimum in general, as
the triangles gradually drift apart in size as subdivision continues.
Should be fairly good, though.

> I gave a solution for this problem about six months ago here on
> comp.graphics, outlining my own algorithm. Basically, you want to
> spread the points out so that they are a maximal distance to each
> other in a least squares sense. This is analagous to placing point
> charges on a sphere: their mutual repellant forces will push them into
> a state of minimal energy: this is (in the least squares sense) the
> "best" solution.

    I did this a few years ago, too, and got in touch with somebody at
CSIRO in Australia (whose email I've lost, unfortunately - maybe he's
still reading comp.graphics). He sent me a copy of a paper he'd
coauthored on this algorithm. They were using it to locate sensors on
a hemisphere for some sort of geophysics information, I believe. And
Greg Turk here at UNC did a SIGGRAPH paper a year or two ago on
reaction-diffusion textures, which does this sort of point
distribution on more complex surfaces as part of the algorithm.

    You can easily get trapped in local energy minima, but this
approach should produce perfectly adequate results for many uses. The
usual problems with numerical methods arise if you're not careful
(using stupid Euler methods without enough damping is a particularly
good way to cause the integration to blow up, of course).

    You can treat it as a constrained N-body problem to accelerate the
computation if you have thousands of particles (why you would need to
do this, I can't imagine).

    Sometime I might get around to generating and posting solutions
for small values of N, along with the resulting sphere tesselations.
--
    Jon Leech (leech@cs.unc.edu)    __@/
    ``The world trusts us with power. It trusts us to be fair and restrained.
      It trusts us to do what's right. '' - George Bush, 1/28/92
From: whart@cs.ucsd.edu (Bill Hart)
Newsgroups: comp.graphics
Subject: Countour Plots  -  Graphics ftp archive  (FAQ?)
Date: 6 Apr 92 16:45:36 GMT

Could someone send me a list of ftp'able archives of graphics routines?
I'm looking for source for generating contour plots.  I have
references describing what to do, but I'd rather not hack up 
what somebody else has already done.

Many thanks,

--Bill
From: olson@anchor.esd.sgi.com (Dave Olson)
Newsgroups: comp.graphics
Subject: Re: SGI IRIX 4.0
Date: 12 Apr 92 20:11:49 GMT
Organization: Silicon Graphics, Inc.  Mountain View, CA

In <1992Apr12.123240.12376@Princeton.EDU> jmo@courant.princeton.edu (Mike Orszag) writes:
| It is not recommended to install IRIX 4.0 yet; there are a lot of little,
| annoying bugs which need to be fixed first. For instance, when compiling
| graphics programs on Power Series machines (this problem does not exist
| on the Personal Irises) one must link to -lfm_s *before* -lgl_s and -lc_s
| or else the compiler comes up with the error: "getcpos: not found". These
| sort of annoying errors occur all the time; since they take time to figure
| out, it probably is not worth it to install the new operating system.
| 
| MIKE ORSZAG

You are mistaken that this is a bug.  You were *always* supposed to
specify -lfm_s prior to -lgl_s.  It was purely accidental that it
sometimes worked the other way (which is reasonable when you think about
it, since font routines need to actually put the chars on the graphics
display).  This "problem" *does* exist on all platforms.

There may well be reasons not to go to 4.0.X, if you have some program
that simply won't work (depends on undocumented features that weren't
carried over, or has dependencies on the NeWS stuff), but not for the
reason listed above.
--
Let no one tell me that silence gives consent,  |   Dave Olson
because whoever is silent dissents.             |   Silicon Graphics, Inc.
    Maria Isabel Barreno                        |   olson@sgi.com
From: teter@vixvax.mgi.com
Newsgroups: comp.graphics
Subject: Re: EMail adress Computer Graphics World?
Date: 7 Apr 92 11:47:40 GMT
Article-I.D.: vixvax.1992Apr7.064740.1738
Organization: Management Graphics, Inc.

In article <1992Apr4.103411.29507@usenet.ins.cwru.edu>, ar559@cleveland.Freenet.Edu (Jan Buitenhuis) writes:
> 
> Hello,
> 
> Does anyone know if the Computer Graphics World magazine
> is reachable by EMail?
> 
> Gr. Jan

Computer Graphics World is on MCI Mail.  You can reach it from Internet by
emailing to cgw@mcimail.com.
From: eric@pencom.com
Newsgroups: comp.graphics
Subject: Distributing Points on a sphere
Date: 15 Apr 92 20:33:42 GMT
Organization: Pencom Software

Here is a stab ....


Task : Distribute points on a sphere as evenly as possible.
Restated : Maximize the distances between the points.
Restated again :
    Maximize the function F(P)
    where P is a set of points and
    F(P) = sum(i = 1 to n,sum(j = 1 to n where i != j, Distance(Pi,Pj)))

    Since the points are on a unit sphere, each point can be easily
    representable by spherical coordinates (theta and psi).

First of all, to take care of isomorphism, we must
fix one point entirely (set theta = 0,psi = 0) and fix one other point
to lie in the same plane as vector 1 (set theta = 0).

Take the partial derivative of F(P) with respect to
     theta(P3) and set to 0
     theta(P4) and set to 0
              .
              .
     theta(Pn) and set to 0
     psi(P2) and set to 0
     psi(P3) and set to 0
              .
              .
     psi(Pn) and set to 0

You will have as many equations as unknowns.  (non-linear, though)
Mathematica anyone?   :-)


Anyone see any reasoning flaws?
From: olson@anchor.esd.sgi.com (Dave Olson)
Newsgroups: comp.graphics
Subject: Re: SGI IRIX 4.0
Date: 12 Apr 92 06:39:37 GMT
Organization: Silicon Graphics, Inc.  Mountain View, CA

In <4602@aquarius.cs.nps.navy.mil> zyda@aquarius.cs.nps.navy.mil (Michael Zyda) writes:

| IRIX 4.0.1: We installed 4.0.1 and MANY things were broken or forgotten
| by SGI. The most irritating problem being that SGI "forgot" that people
| used things like the Spaceball and the Button/Dials box.

No, this wasn't forgotten.  The drivers for these moved from user
apps to kernel drivers, but they did in fact work.  There were some
bugs as I recall.  I don't see any significant fixes since 4.0.1,
except for warping, and support for a newer spaceball; that doesn't
mean there aren't problems; just what was broken for you, and have
you reported it to the support folks?

| Fonts through the font manager are in significantly different places than they were
| in 3.3.2, so many programs have ugly looking interfaces, if they
| used the font manager.

If you mean that the fonts themselves are different, that is correct,
although I seem to recall that for people upgrading from 3.3 the
old fonts were available in a different product image.

| We are now up to 4.0.3 and if you were watching comp.sys.sgi today,
| you saw that "that's fixed in 4.0.5" was announced today. Most of
| our systems run like dog meat (very slow) on 4.0.3 compared to
| 3.3.2 and we are NOT short on memory on the VGXs where this
| slowness is seen.

Well, at least we *tell* you when we are fixing something; we could
just keep quiet like some companies do.

The only things we are aware of that are consistently slower are
opening windows, mainly due to the differences in interaction with
window manager and server (2 programs, instead of 1 in 3.3).

Again, what exactly is slower, and have you talked to support about
it?  We do know of programs that were polling the event queue that
run slower because there can be a much higher number of events.
There are resources that can be set to help this type of program
(see "man glresources" for details).

| Yes, there probably is a 4.1 soon, probably to be released before
| the SGI Developers' Forum next week...

Nope.  4.1 is a ways away (no official dates yet).  Even 4.0.5 will be
a while; since we don't have patches, we sometimes have a few too many
maintenance releases (don't get me started by complaining about lack of
patches, I agree in general).  What the execs and marketing folks will
talk about (or promise!) I have no idea, but take it with a grain of
salt, sometimes they get a bit carried away.

Obviously I speak just for myself, not SGI.
--
Let no one tell me that silence gives consent,  |   Dave Olson
because whoever is silent dissents.             |   Silicon Graphics, Inc.
    Maria Isabel Barreno                        |   olson@sgi.com
Newsgroups: comp.graphics
From: hollasch@kpc.com (Steve Hollasch)
Subject: Re: Polygon Vertices in Clockwise or Counterclockwise Order?
Summary: Solution
Organization: Kubota Pacific Computer, Inc.
Date: Tue, 7 Apr 1992 17:39:56 GMT

jclark@aplcen.apl.jhu.edu (S Clark James Hawkin) writes:
| Given a list of 3 or more polygon vertex points (x,y) with first and last
| vertex point connect to each other.
| 
| How do I code a function that will tell me if vertex list is arranged
| in clockwise or counterclockwise path along the polygon edges?

    There's an easy solution when you're in four-space that really ...

(BTW, folks, my post concerning the triangular pyramid was a _joke_ =)

    To answer your problem, I have to make some assumptions.  First of
all, the vertex ordering depends on where you are.  If they're clockwise
from where you're looking, then they'll be counter-clockwise when you look
at them from the other side.  So I'll have to assume that you understand
that the answer is dependent on the solution.

    It's also dependent on whether you're in a right-handed coordinate
system or a left-handed coordinate system.  I'll assume that you're in a
right-handed coordinate system (Y up, X to the right, and Z coming at
you; left-handed coordinate system is Y up, X to the right and Z going
away from you).

    First compute the normal to the triangle by taking the cross product
of vector A = V1 - V0 and vector B = V2 - V0, and call the resulting
vector C.  Now find the vector from a vertex on the triangle to the view
point, S = E - V0, where E is the eye-point, or view point, or whatever
you want to call it.

    Now just find the dot product between C and S.  If the result is
negative, then the vertices are in a clockwise order.  If the result is
positive, then the result is in counter-clockwise order.

    Now if you're in a left handed coordinate system, then C = B X A.

    (There.  One serious post to attone for previous flippancy.)

________________________________________________________________________
Steve Hollasch                             Kubota Pacific Computer, Inc.
hollasch@kpc.com                           Santa Clara, California
From: paul@taniwha.UUCP (Paul Campbell)
Newsgroups: comp.graphics
Subject: Re: three dimensional geometry
Date: 16 Apr 92 15:45:08 GMT
Reply-To: paul@taniwha.UUCP (Paul Campbell)
Organization: Taniwha Systems Design, Oakland

In article <1992Apr3.182508.1@acfcluster.nyu.edu> reznick@acfcluster.nyu.edu writes:
>all i want to do is, given three vertices [x,y,z] [x1,y1,z1] [x2,y2,z2]
>of an equalateral triangle, how can i compute the fourth vertex needed
>to make a three dimensional triangular pyramid?  (all facets are equalateral
>triangles).  thanks.

Which one?

Hint: find the center of the triangle, calculate a normal, extend it by the
appropriate amount in either direction.

	Paul
-- 
Paul Campbell    UUCP: ..!mtxinu!taniwha!paul     AppleLink: CAMPBELL.P
It's not as well known that 3 days before George Bush puked in the Japanese
Prime Minister's lap our great statesman and diplomat accidently gave the
finger to a whole nation ....
Newsgroups: comp.graphics
From: harti@mikro.ee.tu-berlin.de (Stefan Hartmann)
Subject: Re: ---> Looking for a .jpg format viewer for PC (SVGA)
Organization: ZRZ/TU-Berlin
Distribution: tub
Date: Mon, 13 Apr 1992 18:33:09 GMT

In <psebos.702810923@theseas> psebos@ntua.gr (Panaywths Sebos) writes:

>Hello ......
>I have a lot of .jpg format images but I cannot view them on my PC (SVGA card) .I can only view them on a sparcstation machine
>Can anyone out there help me!!!!!!!!!!??????
>Thanx in advance.....
>        Panos Sebos


Get yourself winjpeg.zip , a win3.x based JPEG viewer. It is shareware.

It is on wuarchive.wustl.edu (128.252.135.4) in pub/MSDOS_UPLOADS

Please don't send me email to mail it to You. Find a friend who has 
anonymous FTP access to download it for You .

Best regards, Stefan Hartmann,c/o Workshop for
Decentral Energy Research

Xref: sparky comp.graphics:5438 alt.binaries.pictures.d:2400 alt.binaries.pictures.misc:4618
From: rolf@let.rug.nl (R.P. Mulder)
Newsgroups: comp.graphics,alt.binaries.pictures.d,alt.binaries.pictures.misc
Subject: Re: JPEG viewer for win3.0 and 3.1
Keywords: jpeg
Date: 15 Apr 92 11:30:10 GMT
Organization: Faculty of Arts & Letters, Groningen University, The Netherlands

In article <5ui7iB1w165w@angus.mi.org> dragon@angus.mi.org (John Lussmyer) writes:

>Actually it's much nicer to convert them to TGA and view them with a
>board that displays 15 or 24 bits per pixel.  Most JPG have the full
>24 bits of info.

This doesn't solve the problem! You still need to convert the files and I 
doubt it that it will be any faster (less slow!) then the JPEG 2 GIF 
convertion.
There is another problem to your suggestion: 15 or 24 BPP boards are pretty 
rare on a PC and that's what the question was all about.

The only real solution is that those guys writing the picture viewers like 
VPIC and CSHOW finally implement the FREE JPEG sourcecode available from the 
independant JPEG group.

Just my $0.02
From: lampert@peachs.enet.dec.com (Pat Lampert)
Newsgroups: comp.graphics
Subject: NURB Examples Wanted
Date: 6 Apr 92 19:48:57 GMT
Organization: Digital Equipment Corporation


Hello,

I'm looking for some PHIGS BSpline Surface examples that contain
trimming curves. Anyone have a good example of reasonable length. Language 
is not a big factor. I would prefer C though. I want to use this for 
learning purposes, and to test DECPHIGS.


Pat


Newsgroups: comp.graphics