HDTenEightyP/NetNews huggingface dataset:
From: srinivas@lgc.com (Manapragada Srinivas)
Subject: Building Geometry Hierarchies
Organization: Landmark Graphics LGC
Date: Mon, 14 Dec 1992 16:40:27 GMT

Hi,

	I am not really sure if this should be a bug report. I am trying to
build geom hierarchies wherein the geometries are being created by different
modules. Unfortunately the geom naming convention of concatenating the module
instance number at the end, prevents this.

	For example consider two Modules A and B, which produce two geometries
G1 and G2 respectively. Furthermore Module A sends the name of its geom "G1"
on a string port to Module B. Module B then tries to set the parent of its
geometry to this name ("G1"). Assume also that Module B waits until the data
on the string port (geometry name) arrives.

	The hierarchy under top shows up as follows

	top
		G1.0
		G1.1
			G2.1

	and if were to guess the correct name of G1 and pass down G1.0 to mod B
	the following hierarchy shows up

	top
		G1.0
		G1.0.1
			G2.1

	Whereas the intended hierarchy was either

	top
		G1
			G2

	or less preferrably

	top
		G1
			G2.1

	Is there any way of turning off the concatenation of the instance
number? I guess am looking for a way by which I can refer to geometries within
a module created by other geometries.

	The only other alternative would be for us to write a module which
would have geometry inputs ( no proper documentation for doing so, and
probably a frowned upon practice ), which would then set up the hierarchies.

	I probably might be missing something, however I searched the AVS4
manuals and AVS5 updates, and didn't find anything which would help me.

	I tried using AVSset_object_group but the group name didn't show up
in the object browser.

	Any help in this matter would be greatly appreciated,

Thanks
Srinivas

Landmark Graphics Corp.

-- 
Yonder, beyond the event horizon!
Newsgroups: comp.graphics.avs
From: petelev@convex.com (Pete Levinthal)
Subject: Re: Building Geometry Hierarchies
Date: Mon, 14 Dec 1992 19:31:28 GMT
Organization: Engineering, CONVEX Computer Corp., Richardson, Tx., USA
X-Disclaimer: This message was written by a user at CONVEX Computer
              Corp. The opinions expressed are those of the user and
              not necessarily those of CONVEX.

>         Is there any way of turning off the concatenation of the instance
> number? I guess am looking for a way by which I can refer to geometries within
> a module created by other geometries.

Place a % (percent character) at the begining of the string supplied in your
GEOMedit_geometry call.  This is from the ConvexAVS 3.9 GEOM Reference section
and should apply to all versions and ports of AVS.

Pete
Newsgroups: comp.graphics.avs
From: avs@ncsc.org (International AVS Center)
Subject: New module at IAC - ucd_extract_new
Organization: North Carolina Supercomputing Center
Date: Tue, 15 Dec 1992 21:48:23 GMT

Name        : ucd_extract_new Version      : 1.000     Mod Number : 1564 
Author      : David Bock, North Carolina Supercomputing Center
Submitted   : 12/15/92        Last Updated : 12/15/92  Language   : C        
Ported to   : DEC IBM
Description : The ucd extract new module is a simple extension to the
              original ucd extract module. This module uses an integer
              instead of a string for one of it's parameters. The module
              can be used in conjunction with animate integer to read and
              visualize a ucd data set across time. By including every
              time step of ucd data at the nodes, animate integer can be
              connected to the integer parameter on this module to select
              and read each time step from memory in succession.
-- 
International AVS Center
North Carolina Supercomputing Center
avs@ncsc.org
From: bosch@rz.uni-karlsruhe.de (Gerhard Bosch)
Newsgroups: comp.graphics.avs
Subject: To whom it may concern:
Date: 18 Dec 1992 10:57:14 GMT
Organization: University of Karlsruhe, Germany
Distribution: world
NNTP-Posting-Host: ifh-hp2.bau-verm.uni-karlsruhe.de

Regarding my postings to the newsgroup about Kubota Pacific
Computer (KPC), I would like to make some clarifications. Since
January 1991, KPC has had its European sales and customer support
operation in Cologne Germany ( tel: +49 221-252-052, CS email:
Support_Europe@kpc.com). The head of the Customer Support
operations in Europe is Mr Gunter Born. KPC's operation in Europe
has suppported the 120 system TITAN customer base since the 
dissolution of Stardent in December of 1991. It has been my own
decision not to purchase service from Kubota either on a contract or
on time-and-materials basis. Mr Born then refused to provide me
free service for a problem which recently occured on my system.
This impasse produced some heated words from me about KPC in my
newsgroup postings. The readers of the newsgroup should know that
my words and opinions are my own and not reflecting of the opinions
of the University of Karlsruhe.

Sincerely, Gerhard Bosch
From: lakerb@rcwusr.bp.com
Newsgroups: comp.graphics.avs
Subject: Help with Creating Colored, Time-Varying, Geometric Object
Date: 15 Dec 92 06:49:50 -0600
Organization: BP Research, Cleveland, OH (USA)

I am setting forth on my first major AVS application.  This involves
visualizing air pollution data superimposed on a map.  The map is a geometry
object and I would like to create colored circles/spheres/objects at four
particular locations on the map.  The color of these objects would vary as
Animated Integer and a Slicer step through a data file of hourly pollution
readings.

In a later stage, the map will become the output of a Field-to-Mesh module,
with the same requirement for colored circles/spheres/objects.

Any suggestions or hints would be most welcome!

Thank you,
Rob Lake
BP Research
lake@rcwcl1.dnet.bp.com
From: tomster@bigwpi.WPI.EDU (Thomas Richard Dibble)
Newsgroups: comp.graphics
Subject: Re: Must 24-bit graphics on PC == DOgS/Windoze?
Date: 18 Dec 92 13:25:04
Organization: ZikZak Corporation
Distribution: na
NNTP-Posting-Host: bigwpi.wpi.edu
In-reply-to: Brandon.Vanevery@launchpad.unc.edu's message of Thu, 17 Dec 1992 21:46:33 GMT

>>>>> On Thu, 17 Dec 1992 21:46:33 GMT, Brandon.Vanevery@launchpad.unc.edu (Brandon Vanevery) said:


  BV> I need to buy a computer and write ray tracers.  I'd love an SGI
  BV> but my budget is more limited than that.  So I feel I'm stuck
  BV> with a souped-up PC.

  BV> All the 24-bit PC boards I know about, have drivers for DOS or
  BV> Windows.  But I need a _REAL_ (i.e. 32-bit) operating system.
  BV> OS/2 is out: to my knowledge, there are no 24-bit OS/2 2.0
  BV> drivers in existence anywhere, nor does anyone plan to make
  BV> them.

Don't count it out so soon!  Most new boards are coming out with os/2
drivers in the boxes (ie, those shipped after about mid-November).  I
hear you can obtain some through ftp (don't know the specifics on
where, though).

Anyways, if you can't find what you need there, and can wait a while,
Windows NT should be out in the next decade or so ... instant support
from graphics board manufacturers from what I hear.

  BV> Is there _ANY_ alternative on a PC?  X Windows under a PC UNIX,
  BV> perhaps?  Anything at all???

  BV> Brandon Van Every

		---- tomster@wpi.wpi.edu

--
/****************************************************************************\
| "I sometimes used to try to catch her, :	FROM:   tomster@wpi.wpi.edu  |
| but never even caught her name."	 :	TO:	who(m)ever reads it  |
|	---- the cure			 :	CC:	programming language |
\vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv/
From: mrj@CIS.Prime.COM (Mohammad Reza Jahanbin)
Newsgroups: comp.graphics
Subject: Re: Calculating polygon areas
Date: 16 Dec 92 17:36:13 GMT
Reply-To: mrj@CIS.Prime.COM
Organization: Computervision R&D Ltd

In article 24617@sophia.smith.edu, orourke@sophia.smith.edu (Joseph O'Rourke) writes:
> In article <Bz994n.JtC@bailgate.gpsemi.com> martin_s@sn4608.oldham.gpsemi.com (Martin Shelley) writes:
> >
> >I would like to know if there are any generalised routines for calculating
> >the area of a 2 dimensional polygon.
> 
> Here is an extract from some text of mine that is not yet published:
> 
> 	So if the coordinates of vertex $v_i$ are $x_i$ and $y_i$,
> 	twice the area of a polygon is given by
> 	\begin{equation}
> 	2 \A( P ) = \sum_{i=0}^{n-1} (x_i y_{i+1} - y_i x_{i+1})
> 	\end{equation}


There is a more general form of the above:

	Area = 0.5 \sum_{i=0}^{n} (P_i X P_{i+1})         

	s.t. i+1 = (i+1) mod n i.e. when i = n then P_{i+1} = P_0

Where X denotes a vector cross product. 

This holds for 2-d or 3-d (coplanar), convex or concave, polygons with n+1 vertices
P_0,...,P_n. Note, if the Area is negative then the order of points are describing a left handed polygon.

The proof is simple. If anyone is interested I'll post it to the net.
---
I dont speak for others and they dont speak for me!

mohammed.
Newsgroups: comp.graphics
From: boebert@sctc.com (Earl Boebert)
Subject: algorithm sought: intersection of line and bezier
Organization: SCTC
Date: Tue, 15 Dec 1992 19:29:52 GMT

Assume one has an arbitrary 2d cubic bezier in xy space, defined by
four control points, and an arbitrary line defined as y = ax+b.
Further assume that it is known that the line crosses the curve at
least once.  Can any kind soul point me to a fast algorithm for
finding the point(s) of intersection?

Many thanks,

Earl (boebert@sctc.com)

Newsgroups: comp.graphics,comp.graphics.animation
From: howe@ccu.umanitoba.ca (Dave Howe)
Subject: REALISTIC 3D STUDIO
Organization: University of Manitoba, Winnipeg, Manitoba, Canada
Date: Fri, 18 Dec 1992 19:55:06 GMT

	Thanks to everyone who contributed to this REALISTIC question.
If you've been following the progression of this topic, it has taken off
in many areas of discussion.
	Now, the point was to try to find out what options I have for
doing image processing on a home system for around $3500 - $5000 CANADIAN.
 Now for the $20,000 part... I was stating that I could not afford the
$20,000 to purchase a system just for my home. 
	
	If anyone cares to comment further, here are some specs:

	- I'm pretty much locked-into using an IBM compatible, due to
	software purchased.
	
	- I only have a limited amount of money available,  but would like
	to add on to the system (ie, single-frame transferring to  VTR).
	
	- I am looking in Gateway 2000, IPC (CDN company), Dell (dimension
	line of PC's.
	
	- VESA looks promising, and the price isn't that much higher.
	
	- How big of a hard drive should I have (REALISTIC).
	
	- Stealh VRAM has been mentioned as being fast, but for windows, 
	how will this help for image processing??
	
	If anyone cares to respond with help, comments, hints, etc.
	I would greatly appreciate any replies.

	Thanks in Advance.

	howe@ccu.umanitoba.ca
------------------------------------------------------------------------------
/////////   /////   ///////
   //	    /   /       /
   //	    /////     /			
   //	    /   /   ///////	
Newsgroups: comp.graphics
From: M16302@mwvm.mitre.org
Subject: Mac-to-Sun Graphics Conversion
Organization: The MITRE Corporation, McLean VA 22102
Date: Thu, 17 Dec 1992 21:35:17 GMT

I need to move some graphics files from McDraw Pro (on a Mac) to a Sun
SPARC.  I can save a McDraw Pro file as McDraw Pro, Pict, Pict2, EPSF, or
MacDrawII 1.1.  Does anyone have a conversion program to convert any of
these formats on the Mac to GIF, EPSI, or CGM for a SPARC.
 
ROBERT B. SHAIN                              EMAIL: RSHAIN @MITRE.ORG
THE MITRE CORPORATION                        VOICE: (703)883-5592
CENTER FOR INTELLIGENCE & SPECIAL PROGRAMS   FAX: (703)883-6991
MAILSTOP W955
7525 COLSHIRE DRIVE                    "MY OTHER COMPUTER IS A CRAY"
MCLEAN, VA. 22102                      "MY OTHER CAR IS A BIKE"
From: gg10@prism.gatech.EDU (GALLOWAY)
Newsgroups: comp.graphics
Subject: Z Buffer Precision and Homogeneous Coordinates
Date: 12 Dec 92 18:16:42 GMT
Organization: Georgia Institute of Technology


I have written a Z-buffer renderer and now a scanline Z-buffer one.
But after going back and reading several new books on the subject, I
find myself confused about the scaling of Z values as part of the viewing
transformation pipeline.  In the new book by Alan Watt and Mark Watt,
"Advanced Animation and Rendering Techniques, Theory and Practice", they
reference Newman and Sproull and say that:

                      B
    Z(screen) = A + ------
                    Z(eye)

where A and B are constants.  And that this is done so that "in moving
from eye space to screen space, lines transform into lines and planes
transform into planes."  The depth value gets normalized from the range
[near, far] to [0, 1].

If the viewing transformation matrix consists of only linear operations,
translation, rotation, and scaling, then this appears to degrade the
precision of the depth value.  In my current Z buffer-based renderer my
Z buffer is an array of 32 bit floats.  I preform clipping in the 3D view
space (or eye space) before perspective projection.

My questions are:

a) Why do software (non-hardware) Z buffers normalize the depth value?
   Why not just keep around a float and compare floats?

b) Are most Z buffers integerized as well?  How many bits?
   What is the advantage?

c) When is the correct time to clip?  And are homogeneous coordinates
   necessary if you are not current rendering NURBs?
   For most surface, except NURBs, W is always 1 anyway, right?

Thanks,

Greg Galloway
gg10@prism.gatech.edu

P.S. Watt's book is excellent and I highly recommend finding a copy.
From: mbc@po.CWRU.Edu (Michael B. Comet)
Newsgroups: comp.graphics
Subject: Re: LBM graphics
Date: 14 Dec 1992 21:02:52 GMT
Organization: Case Western Reserve University, Cleveland, OH (USA)
Reply-To: mbc@po.CWRU.Edu (Michael B. Comet)
NNTP-Posting-Host: slc12.ins.cwru.edu


In a previous article, bbs-cyclic@jwt.UUCP (Ron Czarnik) says:

>Does anybody have the format/structure layout for an ILBM file?  Any help 
>would be appreciated.. thanks. 
>
>Ron
>


	Check out the nwe version of the book "Supercharged Bitmaped
Graphics" by Steve Rimmer.

	Doesn't go into the 4096 color mode....but does handle loading
and saving all other lower color ham formats.


-- 
+======================================================================+
|  Michael B. Comet - Computer Programmer / Graphics Artist  - CWRU    |
|  mbc@po.CWRU.Edu  - "IF THEN THEN THEN = ELSE ELSE ELSE = THEN"      |
+======================================================================+
Xref: sparky comp.graphics:13081 comp.graphics.animation:1389 alt.binaries.pictures.misc:14436
From: tnguyen@shelley.u.washington.edu (Thang Nguyen)
Newsgroups: comp.graphics,comp.graphics.animation,alt.binaries.pictures.misc
Subject: Re: 24 Bit Genoa 7900 board programing info
Date: 20 Dec 92 21:46:18 GMT
Organization: University of Washington, Seattle

hello,
I was wondering if there any any other animation flics
that have been done using ray tracers.
I have seen canyon(nice one) and skyvase(pretty cool) and
another one called snowfli.zip in which there is a rotating
christmas merry-go-round.   any help would be appreciated.
thanks.

tnguyen@shelley.u.washington
Newsgroups: comp.graphics
From: andy@osea.demon.co.uk (Andrew Haveland-Robinson)
Distribution: world
Subject: Re: Faster ray intersector for POV
X-Mailer: cppnews $Revision: 1.14 $
Organization: Haveland-Robinson Associates
Date: Fri, 18 Dec 1992 15:30:37 +0000


In article <BzF6v7.Equ@plato.ds.boeing.com> coy@plato.ds.boeing.com (Stephen B Coy) writes:

>In article <724573602snx@osea.demon.co.uk> andy@osea.demon.co.uk (Andrew Haveland-Robinson) writes:
>>I haven't been through the code in detail, but there must be a few loops
>>that could be unwound a little.  The sluggishness comes from multiplatform
>>code I guess.
>
>In general ray tracing is a slow process.  Right now the best way to
>get the most speed out of POV is to make sure that your objects use
>bounding boxes to help speed things up.  If you are render polygon
>objects you should be using raw2pov which automatically adds the
>bounding heirarchy.  Many people have reported 10-15 times speedups
>with this.  Currently the POV developers are looking into adding
>automatic bounding for a future version.  Until then you'll either
>have to do it by hand or use a different ray tracer like RayShade,
>Vivid, Bob, or MTV.
>
>Stephen Coy
>coy@plato.ds.boeing.com
>
>author of Vivid & Bob
>drinker of fine ales

Indeed Stephen - remember the Vivid/POV polygon benchtest I sent you??
I haven't come across raw2pov before though.

Are raw files of the format:

1
4    4    3    4
1.   1.   5
1.   1.   4
1.   1.   3
1.   1.   2
0.   0.   0.
1.   .55  0.
0.   1.1  0.
333 .55  1.
3    1    1    2    4
3    2    2    3    4
3    3    1    4    3
3    4    1    3    2

Cheers
Andy.

+-----------------------------------------------------------------------+
| Haveland-Robinson Associates   | Email: andy@osea.demon.co.uk         |
| 54 Greenfield Road, London     |        ahaveland@cix.compulink.co.uk |
| N15 5EP England. 081-800 1708  | Also:  0621-88756 081-802 4502       |
+-----------------------------------------------------------------------+
> Some dream of doing great things, while others stay awake and do them <
Xref: sparky comp.graphics:13009 comp.graphics.animation:1359
From: twong@civil.ubc.ca (Thomas Wong)
Newsgroups: comp.graphics,comp.graphics.animation
Subject: Re: POV bug when rendering 640x480
Date: 17 Dec 1992 17:01:00 GMT
Organization: Dept. of Civil Engineering, U.B.C., Vancouver, B.C., Canada
Distribution: world
NNTP-Posting-Host: sam.civil.ubc.ca

In article <1gnr1hINNsu0@kitty.ksu.ksu.edu> sdoran@kitty.ksu.ksu.edu (Steven D. Marcotte) writes:
>
>The same thing happens to me when I render teardrop.pov from the
                                            ^^^^^^^^^^^^
>sample files.  I've done this on both the Sparcs in the lab and 
>my 486 at home and I get the same thing.  It seems to do this
>for any resolution, but from some it is more noticable.  As for a 
>fix, I don't know.  I'd like one though. 

teardrop.pov? Which level of sample was that in? I can't find
it in my distribution. But I haven't had any problems with doing
this resolution with the other samples I have in the distribution.
I'm still using version 1.0. That hasn't been a later version already
has there?

Thomas.

Newsgroups: comp.graphics
From: ricky@danebury.hursley.ibm.com ()
Subject: Re: Public Domain Renderers ?????
Date: Sat, 12 Dec 92 14:58:11 GMT
Organization: IBM UK Science Sentre
Followup-To: comp.graphics

Look in /graphics on princeton.edu

Rick
Newsgroups: comp.graphics,comp.graphics.animation,alt.binaries.pictures.misc
From: jsm1@crux3.cit.cornell.edu (Solitude Standing)
Subject: Simple 3D wireframe rendering method?
Organization: Cornell Information Technologies
Date: 16 Dec 92 20:12:01 GMT

I am looking for formulae to render a three-dimensional wireframe model
onto a three dimensional screen, with a given rotation about any axis.
Basically I am just looking for the conversion method 3D -> 2D.  No
complicated things like hidden surface removal or polygons.  Any help
anyone could provide would be great!  Thanks.


--
Jason Scott MacDonald                    jsm1@crux2.cit.cornell.edu
"Technology sufficiently advanced is indistinguishable from magic."
                                            - Arthur Charles Clarke
END OF LINE
Xref: sparky comp.graphics:12943 comp.graphics.animation:1343
From: sbchanin@ai.mit.edu (Steve Chanin)
Newsgroups: comp.graphics,comp.graphics.animation
Subject: POV bug when rendering 640x480
Date: 16 Dec 92 02:52:33
Organization: MIT Artificial Intelligence Laboratory
Distribution: world
Reply-To: sbchanin@ai.mit.edu
NNTP-Posting-Host: raisin-nut.ai.mit.edu

When I use POV to render samples at 640x480 I get a black bar about 75
pixels from the top of the screen.  It runs all the way from the left
edge to the right edge of the image.  At other image sizes (i.e.
400x300 or 1024x768), this problem doesn't occur.  Has anyone else
seen this?  Is there a fix?

Thanks,
Steve
--
===============================================================================
DOMAIN: sbchanin@ai.mit.edu                                       Steven Chanin
From: sl859@cc.usu.edu
Newsgroups: comp.graphics
Subject: .geom the third number???
Date: 15 Dec 92 20:29:00 MDT
Organization: Utah State University


	In .geom files what does the third number represent?

						wReam...

P.S.  .geom file is one file created when you convert .iob files or TDDD files
I guess to them...  The first number is the number of points , the second
number is the number of polygons, the third???  I have no idea and have always
skipped.
Newsgroups: comp.graphics,comp.graphics.animation,comp.graphics.visualization,alt.graphics
From: scd@cs.brown.edu (Steven C. Dollins)
Subject: Re: Question about CG education
Organization: Dept. of Computer Science, Brown University
Distribution: comp
Date: Tue, 15 Dec 1992 18:40:45 GMT

In article <WALVER.92Dec15070915@kielo.uta.fi> walver@kielo.uta.fi (Ville V. Walveranta) writes:

   Aren't there any schools that use *real* graphics workstations
   (I'm talking about undergraduate programs)in teaching and labs?

At the University of Illinois at Urbana-Champaign, Donna Cox teaches a
two semester animation course in the Renaissance Education Lab, a lab
of 20 or so Silicon Graphics Personal Irises.  The lab is run by the
National Center for Supercomputing Applications and is used for
courses in Engineering, Physics, Math, CS, and the Arts.

   Every single college that offers a programs in computer
   graphics/animation seems to have PCs or MACs in the labs.

As someone else said, they're afordable.  Big machines are usually
funded through research grants or gifted by the companies who will
hope to get product level research out of them in return.

   The best programs I've found so far are offered by RISD (even
   though their program is more conventional and thus is not
   concentrated on computer based animation in any way).

Brown University has a large graphics lab in the Computer Science
department which works in part with RISD.  I'm a first year Ph.D.
here, so I'm not sure of all the ties.  If you are more interested in
the art aspect of animation, I would recommend talking to RISD about
working through our lab.  On the other hand, if you can hack the CS
part, much of the research in the lab is geared towards the user
interface aspects of creating computer animation.

	   -- Willy
   --

    ***********************************************************************
     ***   Ville V. Walveranta      Tel/Fax.....: (510) 420-0729       ***
      ***  96 Linda Ave., Apt. #5   From Finland: 990-1-510-420-0729  ***
       *** Oakland, CA  94611, USA  (FAXes automatically recognized) ***
      ***  GET MY PGP KEY FROM MY PLAN -> Email.: walver@kielo.uta.fi ***  
     ***        "Reality is subject to change without notice"          ***
    ***********************************************************************


					- Steven Dollins
Brown Computer Graphics Group		scd@cs.brown.edu
--
	We have no theology.  We have no philosophy.  We dance.
Newsgroups: comp.graphics
From: loescher@Informatik.TU-Muenchen.DE (Stephan Loescher)
Subject: searching for a VESA driver...
Originator: loescher@hphalle3d.informatik.tu-muenchen.de
Organization: Technische Universitaet Muenchen, Germany
Date: Tue, 15 Dec 1992 12:42:32 GMT


Hi!

I'm searching a VESA driver for the ET4000
(Diamond SpeedStar HiColor).
I have a VESA driver, but it doesn't make HiColor - only 256 colors.

Thanks in advance for any help!

S.L.

My Internetadress: loescher@informatik.tu-muenchen.de