[comp.archives] [graphics...] Re: how to view f

krogh@talon.ncsa.uiuc.edu (Mike Krogh) (03/17/91)

Archive-name: graphics/visualization/isovis/1991-03-15
Archive-directory: ftp.ncsa.uiuc.edu:/isovis/ [128.174.20.50]
Original-posting-by: krogh@talon.ncsa.uiuc.edu (Mike Krogh)
Original-subject: Re: how to view f(x,y,z) = constant surfaces ?
Reposted-by: emv@msen.com (Edward Vielmetti, MSEN)


This type of surface is known as an isosurface.  You can get some public
domain software from NCSA's anonymous ftp server (ftp.ncsa.uiuc.edu or
128.174.20.50 [this may change to 141.142.20.50 any day now]).  After
logging into the server, go into the directory 'isovis' and get the
stuff in there, which includes binaries, source, and documentation.
This code will work on most machines, but has a option for displaying
the output on an SGI workstation.

You can also find a lot of other visualization tools on our server.


Mike Krogh
NCSA
krogh@ncsa.uiuc.edu


In article <1991Mar14.234739.15281@athena.mit.edu>, chasman@athena.mit.edu (David Chasman) writes:
> Umm, I've never read or posted to either of these groups.  What I am looking
> for is some code to take the function zz = f(x,y,z) and render the 3-D surface
> which corresponds to this.  
> 
> Ideally, I'd like C-code for a silicon graphics machine.
> 
> My current technique is to evaluate f(x,y,z) for all discretized
> (x,y,z) inside of a cube - and to light up a point 
> if :
> 	 | f(x,y,z) - constant | < Epsilon
> 
> if you have any ideas - please help.
> 
> --David Chasman
> chasman@athena.mit.edu

[The README file for isovis follows.  Let me know if this was a useful
thing to add and I'll add it when appropriate.  --Ed (emv@msen.com) ]


NCSA Isosurface Visualizer Tar Instructions
August 1990
National Center for Supercomputing Applications
-----------------------------------------------

NCSA Isosurface Visualizer is a 3D visualization tool which allows
a user to generate 3D surfaces of constant value in a simple manner.
Input data must be in the form of a single 3D array of scalar data 
stored as a Scientific Data Set (SDS) in an HDF file.  As output, the 
program can generate a VSet in an HDF file and/or an object file.  Both of
these files contain the polygons that make up the isosurface.  The
VSet may be viewed by a program such as NCSA PolyView.  The object
file is a simple ascii file of vertices and connectivity; and it
may be viewed by programs such as Personal Visualizer from Wavefront
Technologies, Inc.

If the program has been compiled on a Silicon Graphics Iris, then
ISOVIS also gives you the option of displaying the isosurface within ISOVIS.
You can control color selection, scaling, rotation, etc.  You can also save
the resultant image as a raster image in HDF format.  ISOVIS has been set
up as a non-interactive batch utility to enable users the ability to 
create 3D animations from time-dependent data with little effort.

Isosurface Visualizer was written at the National Center for Supercomputing
Applications (NCSA) located at the University of Illinois, Urbana-Champaign.
The software was developed by NCSA's Software Development Group and 
NCSA's Visualization Services and Development Group. 

Software with additional examples may be obtained in the public domain
by invoking NCSA Anonymous FTP:

	1) ftp ftp.ncsa.uiuc.edu /or/ ftp 128.174.20.50
	2) log in using "anonymous" for the name
	3) enter your local login name for the password




------------------------------------------------------------------------------
------------------------------------------------------------------------------
			*** TAR INSTRUCTIONS ***
------------------------------------------------------------------------------
------------------------------------------------------------------------------

In this directory, you will find the following three files:

	README (which is this file),
	isovis.tar.Z, and
	isovis.version

The file 'isovis.tar.Z' is a compressed tar file containing the isovis 
executables along with example data.  To extract the files from 
'isovis.tar.Z', type the following:

	uncompress isovis.tar.Z
	tar -xvof isovis.tar

The file 'isovis.version' is a text file which contains information
about which release of isovis is contained in isovis.tar.Z.

okeefe@cs.Buffalo.EDU (Paul O'Keefe) (03/17/91)

Archive-name: graphics/surfaces/marchingcubes/1991-03-15
Archive: szechuan.ncsc.org:/pub/marchingCubes/marchingCubes.tar.Z [128.109.178.3]
Original-posting-by: okeefe@cs.Buffalo.EDU (Paul O'Keefe)
Original-subject: Re: how to view f(x,y,z) = constant surfaces ?
Reposted-by: emv@msen.com (Edward Vielmetti, MSEN)


In article <1991Mar14.234739.15281@athena.mit.edu>, chasman@athena.mit.edu (David Chasman) writes:
|> What I am looking
|> for is some code to take the function zz = f(x,y,z) and render the 3-D surface
|> which corresponds to this.  
|> 
|> Ideally, I'd like C-code for a silicon graphics machine.
|>

In addition to those already cited:

One)	apE from OSU has a module Onion which implements 
	Lorenson and Cline's Marching Cubes alogorithm.
	It comes with SGI binaries and source. Since apE
	is a complete environment, it can render the results.
	However, apE also comes with a $75.00 price and some
	license restrictions which differ for academic and
	non-academic users. Info on apE is available via
	anonymous ftp at apE.osgp.osc.edu (128.146.18.18).

Two) 	There is a C code implementation of Marching Cubes
	by Steve Lamont formerly of the NC SuperComputer Center.
	It's available via anonymous ftp at szechuan.ncsc.org.

Three)  Although Marc Levoy is most famous for his volume rendering
	algorithm, he also has an iso-value surface rendering algorithm.

@Article{LC:,
  author =      "Levoy, Marc",
  title =       "Display of Surfaces from Volume Data",
  journal =     IEEE Computer Graphics and Applications,
  year =        1988,
  month =       "May",
  volume =      8,
  number =      3,
  pages =       "29-37"
}

-Paul O'Keefe