HDTenEightyP/NetNews huggingface dataset:
From: jef@netcom.com (Jef Poskanzer)
Newsgroups: comp.graphics
Subject: Re: FAQ as requested
Date: 31 Jul 92 15:59:12 GMT
Reply-To: Jef Poskanzer <jef@netcom.com>
Organization: Paratheo-Anametamystikhood Of Eris Esoteric

sjm@miles.com (Scott Mark):
}So saying "hand it over" is bullshit.  If someone wants to figure out what
}questions belong and do the research for the answers, then let 'em.
}But an obviously ungrateful group of people don't deserve the results of
}the work that Jef did.  So write your own FAQ, Art.  Get a set of questions,
}look up the answers, and you can start posting Art's Very Own c.g. FAQ.

It's not even that.  I am actively searching for someone to take it
over.  I have no problem whatsoever against the readers of comp.graphics
in general.  99% of them never post, and 90% of them probably didn't
even notice either FAQ.  I do have a problem with Nick's rudeness and
arrogant incompetence.  I also have a problem with Juhana reposting the
FAQ *without permission*.  In fact, if he had had the common human
decency to ASK FIRST, he would probably be the officially annointed
keeper of the FAQ right now, with all my blessings.  But now that he
has demonstrated his own rudeness, that will not happen.

I'm still waiting to hear from the siggraph folks who said they'd take
it off my hands.  Anyone else who's interested, please step forward.
And as usual, ignorant flames go into the bit bucket.
---
Jef

           Jef Poskanzer  jef@netcom.com  jef@well.sf.ca.us
           You are in a maze of little cubicles, all alike.
From: davis@gauss.enet.dec.com (Peter Davis)
Newsgroups: comp.graphics,alt.book.reviews
Subject: Re: Graphics book
Date: 30 Jul 92 20:28:49 GMT
Organization: Digital Equipment Corporation


In article <1992Jul30.183238.6202@magnus.acs.ohio-state.edu>, mmasood@magnus.acs.ohio-state.edu (Mohammed A Masood) writes...
>Hi, could any one on the net recommend a good book which deals with different
>kinds of graphics files, .gif, tiff, rtt and so on.  I mean a book explaining
>these files and telling us how to convert from one form to another
>Thanks in advance

From an earlier posting:
===============================================================================
Newsgroups: misc.books.technical
From: johnl@iecc.cambridge.ma.us (John R. Levine)
Subject: Graphics File Formats
Organization: I.E.C.C.
Date: Mon, 8 Jun 1992 05:57:17 GMT
David Kay and John Levine (that's me,) "Graphics File Formats,"
Windcrest/McGraw-Hill, May 1992, ISBN 0-8306-3059-7 $24.95 paper,
ISBN 0-8306-3060-0 $36.95 hardcover, 278 pp.

The book is at last actually available -- it showed up in my local
bookstore June 1.

We describe many major graphics file formats.  For most of them (all
but JPEG and CGM) we go all the way down to the bit level so there's
enough to write code that handles the file format.  We've attempted
to include as much folklore as we can, e.g. the facts about PCX that
aren't in the Z-Soft handout, poorly documented proprietary TIFF
content types, and which fields in a TGA file people really use.

Table of Contents

1	Graphics Representation Theory
2	Formats and Applications

Bit Maps
--------
3	Z-Soft PCX
4	MacPaint
5	Aldus Tagged Image File Format
6	Compuserve Graphics Interchange Format
7	Digital Research Gem IMG
8	IFF/ILBM
9	Truevision Targa
10	Microsoft Windows BMP
11	Sun Rasterfile
12	Unix PBM
13	X Window XBM
14	X Window XWD
15	JPEG
16	FITS

Vectors
-------
17	Autocad DXF
18	Hewlett Packard HP-GL
19	Lotus PIC
20	Unix Plot(4)

Printers
--------
21	Hewlett Packard PCL
22	Adobe Encapsulated Postscript

Display Lists or Metafiles
-----------------------------
23	Microsoft Windows Metafile
24	Apple Macintosh PICT
25	ANSI Computer Graphics Metafile

26 Other Formats

-- 
 John R. Levine, IECC, POB 349, Cambridge MA 02238, +1 617 492 3869
johnl@iecc.cambridge.ma.us, {ima|spdcc|world}!iecc!johnl
"If you can't live without me, why aren't you dead yet?"

===============================================================================
From: zhu@sgi.com (Benjamin Zhu)
Newsgroups: comp.graphics
Subject: Re: Converting polygon with concave boundary to convex one anybody?
Date: 28 Jul 92 15:28:12 GMT
Organization: Silicon Graphics, Inc.

In article <9207281143.AA27417@ucbvax.Berkeley.EDU> sm@cs.hull.ac.uk, S.Marshall@hull.ac.uk writes:
>
>I have a group of planar polygons with concave boundaries.  I wish to replace
>each of these polygons with a number of triangular ones.  For a polygon with a
>convex boundary, it's quiet easy.  All I do is pick a single polygon vertex and
>form triangular facets, using this vertex, with successive pairs of vertices
>around the polygon boundary.  The single polygon vertex is therefore common to
>all triangular facets.
>
>This, of course, will not work for polygons whose boundaries are concave, since
>a triangular facet may lie outside the boundary of the polygon.  So either I
>must use a different method of generating triangular facets, or firstly
>generate polygons with convex boundaries from the polygons with concave
>boundaries.
>

	Well, I finally got ten-minute free time before flying to Siggraph.
	No rescue after siggraph though. Hopefully, I can help you out
	before I plunge into endless ucode and bug fixes again.

	Look up Preparata and Shamos book, ``Introduction to Computational
	Geometry.'' They elaborated a number of O(n*log(n)) algorithms
	there to do what you wanted.

	As long as you have a 2-3 tree or an avl tree implementation around,
	it should be pretty straightforward to implement any of these
	algorithms.

	See you guys at siggraph. Do not forget to drop by our booth. Our
	Venice machines (marketing buzz words, RealityEngine) are going to
	knock many people's pants off:-)

	Ben

--
Benjamin Zhu             ;;; ``Recently-promoted shinto'' priest of microcode
Silicon Graphics, Inc.   ;;; ``Just call my name, I will be there.''
zhu@graphack.asd.sgi.com ;;; ``Projective geometry is all geometry.'' - Cayley
(415) 390-1187           ;;; ``Learn forever, young forever.'' - Anonymous
From: spl@alex.uucp (Steve Lamont)
Newsgroups: comp.graphics
Subject: Re: THANKS! for tif to gif help...
Date: 30 Jul 1992 20:10:00 GMT
Organization: University of Calif., San Diego/Microscopy and Imaging Resource
NNTP-Posting-Host: alex.ucsd.edu

In article <mktjadx.712519928@gsusgi1.gsu.edu> mktjadx@gsusgi2.gsu.edu (Jeff A. Dilcher) writes:
>Thanks to all who took time to send me help on .tif to .gif 
>conversions, and especially to:
> 
>Steve Lamont
>Mr D Ingles
>Richard Breuer
>Steve Lamont

Gosh... I must be twins. :-)

							spl
-- 
Steve Lamont, SciViGuy -- (619) 534-7968 -- spl@dim.ucsd.edu
UCSD Microscopy and Imaging Resource/UCSD Med School/La Jolla, CA 92093-0608
"Out of the ash/I rise with my red hair/And I eat men like air."
                        - Sylvia Plath, "Lady Lazarus"
From: bam+@BAM.GARNET.CS.CMU.EDU (Brad Myers)
Newsgroups: cmu.cs.general,comp.graphics
Subject: Help with sorting rectangles
Date: 31 Jul 92 18:43:32 GMT
Organization: School of Computer Science, Carnegie Mellon
Originator: bam@BAM.GARNET.CS.CMU.EDU


Does anyone know an algorithm for sorting rectangles in row-major order?
The problem is that they might not be exactly aligned.  For example:

         |-----|
  |----| |  B  | |-----|
  | A  | |     | |  C  |
  |____| |-----| |_____|
        
|-----|         |-----|
| D   ||-----|  |  F  |
|-----||  E  |  |     |
       |_____|  |-----|


I want to get the order ABCDEF which is "clearly obvious", but notice
that D has an X value that is less than A, and B has a Y value that is
less than A (assuming 0,0 at the top), so simply sorting by X and then
Y (or vice versa) fails.  Surely, someone has solved this problem already!

Thanks for your help!
Brad Myers
bam@cs.cmu.edu
Newsgroups: comp.graphics
From: jb@falstaff.MAE.CWRU.Edu (Jim Berilla)
Subject: Re: Image Processing Package..JAVA?
Keywords: Image Processing
Organization: Case Western Reserve University, Cleveland, Ohio, USA
Distribution: usa
Date: Thu, 30 Jul 92 22:14:32 GMT

In article <1568jiINNscn@matt.ksu.ksu.edu>, sngattan@matt.ksu.ksu.edu (Sanjay N Gattani) writes:
|> 	Does anyone out there know anything about JAVA image processing
|> software?  I think it is marketed by Jandel Scientific, a company
|> in California.  What I would like to know is what type of image files
|> can it accept?

It works with TIFF files, but will only accept files with the Intel(TM) byte
order.  Also, the files that it put out have some non-standard type fields.

-- 
      Jim Berilla / jb@falstaff.MAE.cwru.edu / +1 216 368 6776
From: sacchi@hpl.hp.com (Cristiano Sacchi)
Newsgroups: comp.graphics
Subject: Re: fitting to a NURBS surface
Date: 23 Jul 92 17:03:42 GMT
Article-I.D.: hplabs.Bruq27.BCn
Distribution: na
Organization: Hewlett-Packard

Look for Computer Graphics and Applications. Last year
there was a survay about NURBS written by Les Pigl.
Unfortunately I don't remember the issue number but you
can find it easily.
I think it is what you need.

Cristiano Sacchi

sacchi@cad.imu.mi.cnr.it
Newsgroups: comp.graphics
From: exk11@po.CWRU.Edu (Erik Kangas)
Subject: Re: Programming mouse ? in graphics mode
Reply-To: exk11@po.CWRU.Edu (Erik Kangas)
Organization: Case Western Reserve University, Cleveland, OH (USA)
Date: Fri, 24 Jul 92 17:12:39 GMT


In a previous article, csblm@uxa.ecn.bgu.edu (Brian Murphy) says:

>I am very new to graphics programming and am trying to do something
>that is probably very simply for most who will read this posting but
>difficult for me.  I am trying to set my graphics mouse cursor in C for
>a microsoft compatible mouse.  I have very brief documentation on how to
>by using a 16 x 16 bit block with screen and cursor bits to generate the
>image.  I'm lost as to just how to create this graphics cursor.  Any
>direction either on how to or doc to find on the network would be
>greatly appreciated.
>
>Many thanks
>Brian L. Murphy
>Eastern Illinois University
>
I just finished a mouse driver that supports all bgi (borland c/c++) (and pascal) graphics modes.  It allows the user to redefine and create his own
cursors in 256 colors (or 16...).  It's shareware, but unless you want the
source code or want to create commercial programs, you don't need to regester it.

It is located on the ftp server "wuarchive.wustl.edu" in the directory
"/pub/MSDOS_UPLOADS"  it is called "mmouse10.z"  It is actually a zipped file
that lost the last 2 letters of its name extention.  The readme file included
should provide adequate documantstion for whatever you want to do. If you
have any questions or problems let me know by email.

-- 
Erik Kangas  
Physics/Math/CompE         "I lift up mine eyes unto the hills whence  
Phone 754-2316              cometh my strength"  Psalms                
Zeta Psi #304               Whereof we cannot speak, Thereof we must be silent.
Newsgroups: comp.graphics.explorer
From: xeno@iastate.edu (Gary L Snethen)
Subject: Re: Curvilinear and interpolate
Organization: Iowa State University, Ames IA
Date: Tue, 28 Jul 1992 00:19:33 GMT

In <mikep.712262803@pv7b88.vincent.iastate.edu> mikep@iastate.edu (Michael K Patterson) writes:

>When I feed 2d curvilinear data and a GENLAT lattice into interpolate,
>many of my points are lost (become 0). Reading from the man page:

>     KNOWN PROBLEMS
>          For interpolation of a point lying outside of a curvilinear
>          Source, a zero value is returned without any indication that
>          the point lies outside the known grid.

>Hmmm. can someone tell me what's wrong, or what I'm missing, or if It's not
>me, what the problem is, so that I can work around it?


>Thanks
>------------Michael Patterson
>(mikep@iastate.edu)

Well Mike,

   It sounds to me as though there are some coordinates in your interpolation
lattice that lie outside your data's coordinates...  In order to be
interpolated, the point must lie within (ie., be surrounded by) your data.

Imagine a 1D interpolation...  if I said that at point 2 the value was 5
and at point 4 the value was 3, then you could interpolate for point 4 
(yielding a value of 3), but not at any points less than 2 or greater than 4.


Hope this helps (and is accurate...)

---Xeno

;)
Newsgroups: comp.graphics.explorer
From: wsh8z@amsun27.apma.Virginia.EDU ()
Subject: Some novice question.
Originator: wsh8z@amsun27.apma.Virginia.EDU
Organization: University of Virginia
Date: Thu, 30 Jul 1992 14:13:59 GMT

I have just started using explorer. Right now I am fooling with
images. I would like to print them on a PostScript printer. Is there a
conversion utility which converts from SGI rgb format to PostScript
format? The images are all greyscale.

I was also wondering about the manuals. I only have the "Getting
started with Explorer" manual and the few chapters of the users guide
supplied in the /usr/explorer/doc directory. Are the manuals
expensive? Are they necessary, or are all of them necessary? I am
trying to build modules around my own code using mbuilder and am
afraid it might be impossible without the manuals.

Thanks,

Will Heyman	wsh8z@virginia.edu	UVA Applied Math
From: rlb@lavalite.corp.sgi.com (Robert Brown)
Newsgroups: comp.graphics.explorer
Subject: Re: Source ?
Date: 23 Jul 92 03:06:03 GMT
Organization: sgi

In article <39347@skye.dcs.ed.ac.uk>, gordonc@epcc.ed.ac.uk (Gordon Cameron) writes:
|> Is there any real good reason why SGI wouldn't make the
|> ReadMovieBYU source code available as a real good example
|> of working with Pyramid data.  The example in the manual
|> leaves a little to be desired.
|> 

There are not many good reasons for why SGI wouldn't ship the source
to a fair number of modules that don't have other license restrictions
from other authors.  We agree that an easy way to learn about how to write
modules, especially those that work with Pyramids, is to look at existing code.

Also, the module writing guide is under extensive revision; pyramids are
one of the focusses of that work.

Bob
---------------
Robert L. Brown
Silicon Graphics, Inc.
From: shreiner@arioch.csd.sgi.com (Dave Shreiner)
Newsgroups: comp.graphics.explorer
Subject: Re: 2 questions
Date: 26 Jul 92 03:45:32 GMT
Organization: Silicon Graphics, Inc.

In article <1992Jul26.021149.15167@cc.gatech.edu>, sougata@cc.gatech.edu (Sougata Mukherjea) writes:
> Hi,
> I am trying to develop some modules in the explorer and have these 2 questions:
> (1) I have opended a Gl-Motif window and I want to divide it into 4 equal parts
>     to show 4 different views (Perspective, Top, Front, Side) of an object.
>     I am drawing the object using gl but my problem is dividing the window so
>     that in each a different view can be shown.

   I'd take a look at the viewport() command.  It controls where you're 
graphics are going to be drawn in the window.

> (2) I want to build up a dialog box similar to the Connections window that pops up
>     in the module builder. Specifically, on two sides of my window various buttons 
>     would be shown. The user can connect a button from 1 side to a button in the 
>     other side. Once connected, the connection would be shown by a blue line (as
>     is the case for all connections in Explorer). What is the easiest way to write
>     this code?

    Given that you probably have only GL and X/Motif to choose from, its got
to be one of them.  Buttons and popups like Explorer uses are a result of
Motif, so that would be the easiest for that.  Since you can't mix X and
GL in a window, if you choose that route, then you'd need to draw the wire
using Xlib.  Its my guess that's how Explorer renders the wires and the like.

> 
> Hope someone can help!
> ==============================================================================	
> Sougata Mukherjea (sougata@cc.gatech.edu)
> Graphics Visualization and Usability Center
> College of Computing
> Georgia Tech
> =============================================================================

Hope that helps.

Thanx,
Dave

  ---------------------------------------------------------------------------

   Dave Shreiner                                        <shreiner@sgi.com>
   Silicon Graphics, Inc.                                (415) 390 - 5063

  "Silently screaming I bang my head against the wall" - Suicidal Tendencies
Newsgroups: comp.graphics.explorer
From: sougata@cc.gatech.edu (Sougata Mukherjea)
Subject: 2 questions
Reply-To: sougata@cc.gatech.edu
Organization: College of Computing
Date: Sun, 26 Jul 1992 02:11:49 GMT

Hi,
I am trying to develop some modules in the explorer and have these 2 questions:
(1) I have opended a Gl-Motif window and I want to divide it into 4 equal parts
    to show 4 different views (Perspective, Top, Front, Side) of an object.
    I am drawing the object using gl but my problem is dividing the window so
    that in each a different view can be shown.
(2) I want to build up a dialog box similar to the Connections window that pops up
    in the module builder. Specifically, on two sides of my window various buttons 
    would be shown. The user can connect a button from 1 side to a button in the 
    other side. Once connected, the connection would be shown by a blue line (as
    is the case for all connections in Explorer). What is the easiest way to write
    this code?

Hope someone can help!
==============================================================================	
Sougata Mukherjea (sougata@cc.gatech.edu)
Graphics Visualization and Usability Center
College of Computing
Georgia Tech
=============================================================================
Newsgroups: comp.graphics.explorer
From: dres@qdpii.comp.qdpi.oz.au (Drought Research Account)
Subject: PseudocolorImg
Organization: Queensland Dept Primary Industries.
Date: Thu, 23 Jul 1992 03:01:21 GMT

Recently I pulled SGI's PseudocolorImg module off the edinburgh ftp site.
It works fine on byte lattices, but doesn't seem to cope with other
primitive data types. If it really only wants byte data, it should have
its input port so configured, invoking the automatic type coercion. If
not, what else does it need to work with other data types ? Any clues 
anyone  (especially SGI) ? I checked the mres file, and it is currently set
to allow any primitive data type.

cheers

Neil Flood
From: pecquet@ohstpy.mps.ohio-state.edu
Newsgroups: comp.graphics.explorer
Subject: data ref counts and shared mem exhausted???
Date: 30 Jul 92 17:40:25 EDT

Hello,
     I have been having difficulties with modules that I have written 
crashing with "exhausted shared memory" errors.  This can be as simple as 
two ReadLat's connected as inputs to a module that:
     creates internally a new lattice to duplicate (in shape/size) one   
       of the input lattices
     create a lattice four times larger than the other input lattice (it is
       a "4 vector" of the "1 vector" input lattice
     using the two input lattices values are copied into the "4 vector"
       output lattice
     the internal lattice (1st step above) is dereferenced:  i.e.:
       cxDataRefDec(lat);
     nothing else is going on as far as data allocation/deallocation is
       concerned

     With two lattices of about 1.5MB (and having a .explorerrc file in my 
home directory containing: arenasize 40mb) the above works several times, 
then (at a random execution) dies with the shared memory exhausted error.

     A related question: some of my modules need global data.  I create 
lattices and then use cxDataRefInc(lat) on them.  When I need to resize 
them, I call cxDataRefDec(lat) and lat = cxLatNew(...).  Does this cause 
the unwanted lattices to be discarded and reclaimed by explorer???
    Any help would be greatly appreciated...
-Joseph
pecquet@mps.ohio-state.edu
pecquet@ohstpy.bitnet
From: robertl@cwi.nl (Robert van Liere)
Newsgroups: comp.graphics.explorer
Subject: Re : Explorer User's Group Meeting
Date: 23 Jul 92 14:40:03 GMT
Organization: CWI, Amsterdam


Can the people that are not in Chicago next week take part in
this meeting ? It seems to me that, in this hi-tech era, something
along these lines could be arranged (perhaps the ftp site
managers, as an added bonus, could arrange something ...).

-- Robert


-- 
Robert van Liere, Department of Interactive Systems,
Center for Mathematics and Computer Science (CWI)
Kruislaan 413,  1098 SJ  Amsterdam,  The Netherlands
email: robertl@cwi.nl | tel: +31-20-592-4118 | fax: +31-20-592-4199
Newsgroups: comp.graphics.explorer
From: jyp@swarm.wustl.edu (Jerome Plun)
Subject: Shared .mres file between modules - Naming problem
Keywords: .mres, share
Organization: Washington University in St. Louis, MO
Date: Tue, 28 Jul 1992 02:08:59 GMT

  I am trying to create a set of modules all having the same interface
(control panel, input and output ports), each generating some data set based
on some specified behavior.
  I wrote a variant of the Imakefile/Makefile that mbuilder generates that
creates a new module (say M), install the code in /usr/local/explorer/modules,
and creates M.credits, M.help, M.mres as soft links to 3 files common to all
the modules.
  Unfortunatly, the name of the module seems to be stored in the resource file
and I am unable to load any of my modules.  If I rename one module to the
base name of the 3 common files, I can start the module in explorer.
  I looked at the content of my resource files and found several places where
the module name is stored.  I am willing to create separate instances of the
resource file but want to automate that so that there is no need for the user
to use mbuilder.

  So:
  1) Is there a way to share resources between modules?
  2) If not, what is the structure of a resource file, or what should I
change in it to accommodate the new module name?

  Thanks. Jerome


-- 
Jerome Plun            []  Is it a crime to want something else?
jyp@swarm.wustl.edu    []  Is it a crime to believe in something different?
Washington University  []  
St Louis, MO           []  "Smalltown England", New Model Army, Vengeance
Newsgroups: comp.graphics.explorer
From: hashimoto@sgi.com (Roy Hashimoto)
Subject: Re: Indigo/XS Explorer oddities revisited
Organization: Silicon Graphics, Inc.
Date: Fri, 24 Jul 1992 19:33:20 GMT

In article <BrqMDI.IxJ@helios.physics.utoronto.ca> mark@cita.toronto.edu writes:
>I posted this to comp.sys.sgi a couple weeks ago, but there were no replies,
>either from SGI folks or from knowledgeable Explorer users.  Now that this
>newsgroup is up and running, I'll repost it here.  Briefly stated, Explorer
>seems to misbehave when rendering on an Indigo/XS without the z-buffer.  Is
>this a limitation (if so, where is it documented?), or is it a bug (in other
>words, should Explorer be smart enough to recognize that there is no z-buffer
>and do its rendering differently)?

The Explorer Render module will run on machines without z-buffer graphics,
but will not properly z-buffer the picture.  No effort is made to compensate
by doing software z-buffering at a higher level than the GL.  I'm not sure
if this is documented in the release notes.

With the absence of the z-buffer, the priority of objects in the window will
be their drawing order and not the viewing distance order.  Most scenes will
look quite strange.

Roy Hashimoto
hashimoto@sgi.com