Newsgroups: comp.archives Path: utzoo!news-server.csri.toronto.edu!ox.com!msen.com!emv From: krogh@talon.ncsa.uiuc.edu (Mike Krogh) Subject: [graphics...] Re: how to view f(x,y,z) = constant surfaces ? Message-ID: <1991Mar16.201618.10029@ox.com> Followup-To: comp.graphics,comp.graphics.visualization Keywords: isosurfaces Sender: emv@msen.com (Edward Vielmetti, MSEN) Reply-To: krogh@talon.ncsa.uiuc.edu (Mike Krogh) Organization: Nat. Cnt. for Supercomputing Appl. References: <1991Mar14.234739.15281@athena.mit.edu> <1991Mar15.152835.24927@ux1.cso.uiuc.edu> Date: Sat, 16 Mar 1991 20:16:18 GMT Approved: emv@msen.com (Edward Vielmetti, MSEN) X-Original-Newsgroups: comp.graphics,comp.graphics.visualization 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.