Visualization Software Packages

1. Visualization Software Packages Scott A. Klasky PPPL September 25, 2000

2. Figure 10: Example of the Volume Visualization of two adjacent teeth; left: Vtk; right: OpenDX. The number of triangles in both surfaces are approximately equal. Figure 11: Examples of the Volume Visualization of a molar; left: VTK; right: OpenDX Outline • VDE2000, VDE2001 • What is visualization? • Who cares? • Criteria to judge a visualization package. • Visualization Packages • Amira • AVS • AVS/Express • IDL • IRIS Explorer • OpenDX • PV3 • SciRun • VisAD • VTK • Conclusions • Demo Scott Klasky (PPPL)

3. VDE2000, VDE2001 • VDE2000: April 27-28 2000 • Held at PPPL with 152 people in attendance • http://w3.pppl.gov/vde2000 • Goal was to provide audience with knowledge of the popular Visualization Development Environments. • The winners: Amira and OpenDX • VDE2001: April 26 – 27 2001 LBNL/NERSC Session 1 Session 2 9-2 Software vendor overview 9-11 What's new/changes vendors 11-2 University Vis. Tools 2-6 User talks 2-4 Panel 1: Defining Scientific Visualization Benchmarks 4-6 Panel 2: Extensions to Vis. packages for distributed memory environments Session 1 Session 2 9-12 User talks 9-12 Hardware vendors 9-10 Poster Session 1-5 Showdown Scott Klasky (PPPL)

4. Figure 3.IRIS Explorer session using remote isosurface computation What is visualization? • Data Visualization is the process of representing data as a graphics display on a screen. • Visualization gives you: • Insight into your data by allowing you to interact with your data. • Enables you to analyze and obtain new information. • Enables you to present your data with others. • Visualization tells the story of your data. • Good stories capture people’s attention, and make them ask questions to gain new insights. • Interaction with the data. • Visualization systems should allow us to interact with the data easily. • Rotations/Translations/Zooms, Time animations, etc. must be FAST! • Visualization Techniques • Isosurfaces • Volume Rendering • Slicing/Clipping • Extraction (3D->2D->1D) • Stream Lines Scott Klasky (PPPL)

5. Who cares! • Back in the stone-age, researchers had X-terms which were incapable of scientific visualization. • In the future (days to come) we will have PC’s with fast graphics cards! • The world will seem like a different and better place • New CAD (Dell machines) has changed the way the engineers are working. • 3D vis. Packages will be available on your desktop! • Your needs can be incorporated in what we do here for visualization! Scott Klasky (PPPL)

6. Criteria to judge a visualization package • Quality of the Output • Accuracy of the output • Ex: There are many isosurface routines which miss triangles, • Aesthetic quality of the output • Speed of Common Visualization Routines. • Isosurfaces, Streamlines • Contour Plots, Volume Rendering • Speed for rotations/translations/zooms. • Ease of Use • Need statistical sample of users • How many lines of code does it take to create everyday visualizations. • Number of Visualization and numerical modules available. • Cost Scott Klasky (PPPL)

7. AMIRA • PPPL is in the process of obtaining the license ($3000/node locked license) (AmiraDev), $1K for Amira 2.1 (non extendible). • At VDE2000, they showed the most impress 3d graphics. • Data Flow environment, with less tools than DX, Express, but the tools it includes are more powerfull. • 120 modules to visualize, analyze and process data. • TCL command language for scripting or vis. Network editing. • Extendible with the AmiraDev edition (will be available in a another week). • Extendible means that we can create new modules in the system. • Will be primary used at PPPL for end visualizations (not as much for everyday visualization, unless it proves to be extremely powerful. • Stereo Support Scott Klasky (PPPL)

8. AVS • Not recommend by Muse/AVS if you have AVS/Express. • Similar to IRIS Explorer and IBM DX. • All 3 products came on the market about the same time (AVS was the first). • Does not have custom UI modules. • More difficult to use c.f. Express. • Does not support vector postscript output. • Not supported at PPPL • Stereo support • Demo Scott Klasky (PPPL)

9. AVS/Express • AVS/Express is a multi-platform, component-based software environment building applications with interactive visualization and graphics features • We have 6 licenses (5 vis. editions), 1 developers edition). • Solaris 2.7 (for Express 5.x)…. Solaris 2.6 (for express 4.2), Dec Unix, Linux (wait for Express 5.5->soon). • 5 licenses for $5K (Vis. Edition), $5K for 1 developers license. • Stereo graphics support • Seems to be the most powerful visualization package here at PPPL. • 2x+ faster than DX for Xianzhu Tang’s datasets. • Demo Scott Klasky (PPPL)

10. IDL • Great imaging software. • Complex method of Visualization: Non-pipeline-dataflow program. • Rendering Quality is not as good as other products. • Very difficult to program for visualizaton: examples: VDE2000data, VDE2000data2 • Not considered a Vis. Product by Vis. Experts • Demo Scott Klasky (PPPL)

11. IRIS Explorer • Best Quote from VDE2000, “…explorer used to be everybody's favorite when DX was not free and SGI IRIS Explorer was, now we are in trouble…” • Better than AVS, but still uses the same architecture. Memory is copied between modules. • Has a collaborative interface. • Stereo support • Link to NAG math routines. Scott Klasky (PPPL)

12. OpenDX • Similar to AVS • Released to the open public May 18, 1999. • Is well tested, widely used. • SMP-thread based • Support is continuing for this product from the mailing lists. • Will be a PPPL supported Vis. Package. • Very good data model • Can run separate modules on separate computers. • Does not support vector postscript output. • DDX!!!!!!!! • Demo Scott Klasky (PPPL)

13. PV3 • More of a university product by Bob Haimes (MIT). • Built on top of PVM, and made to run on parallel computers. • It co-processes the visualization of data generated on a parallel computer. • Data generated from large scale scientific simulations can inflict huge burden on those tasked in assisting the scientist with understanding the results. • Data from one simulation can occupy terabytes of data.  Compress the data so it can be visualized. • PV3 does not perform traditional scientific visualization on the data-set after it has been generated. • It deals with the volume of data concurrently with the solver. • PV3 works for parallel fluid simulations. • It contains all of the extraction tools used for these simulations including: • geometric cuts • iso-surfaces • Streamlines • transient particle traces • … • These abstracts are stored on disk, and transferred to the vis. Machine. • Not easy to set up! Scott Klasky (PPPL)

14. SciRun • Chris Johnson (Utah) is the creator of this code • Is trying to create this is a commercial product. • Is geared for medical researchers. • Scientific Programming environment • Provides for the construction, debugging and steering of large scale computer simulations • Extendible. • Visual Programming • Mainly used for “Steering”, where the simulation is built with tools in Scirun. • Runs on the Origin 2000, and other SGI’s. Scott Klasky (PPPL)

15. VisAD • Created by Bill Hibbard (Wisconsin). • Mainly used for weather applications. • Pure Java (Java2) • Uses Java3d and Java2d • Fully collaborative. • Fully platform independent (even runs on Macs…. Sort of->OsX). • Supports computational steering. • Users must program in Java (or now Python) to get their vis. • Not for serious 3D visualization, but great for 2d vis., and some 3d vis • Has a nice Visualization SpreadSheet program that lets you get nice visualizations without programming. Scott Klasky (PPPL)

16. VTK (Kitware) • OpenSource • Used for 2d Imaging, 3d graphics and visualization. • Distinguishing feature is the integration of functionality, support of supercomputing and activie community support. • Designed as a toolkit (NOT A SYSTEM). • It is meant to be embedded into an application in combination with other tools. • VTK’s core is in C++ • Wrapped with TCL/TK, Java, Python. • Contains the most advanced visualization routines, although the other products are already incorporating these in their products. • Contains streaming support, which allows VTK to handle large (Terabytes) data-sets. • PPPL (with Stanley Dunn) worked on Parallel VTK with Kitware and Los Alamos. • Results were poor, and we viewed this as difficult to use. • To use, we must have the VTK manual by our side to know the interface of modules. • Used mainly by vis. Experts. • Demo Scott Klasky (PPPL)

17. Conclusions • PPPL supports the following vis. Packages. • IDL: Bill Davis et. Al. • AVS/Express • Easy to add modules • Easy to program • fast! • AVS but users should work with Express, since we will not continue our license for this product, since Express can use AVS networks. • OpenDX DDX: It’s Free, and it uses SMP->thread based, and it will eventually run on parallel clusters. • VTK If there parallel implementation gets better (a complete rewrite of their system), and if they start to build a visual front-end, then we will look into this product again. • Amira??? If it can produce sexy pictures easily, then we should pay attention to this product…. Coming soon??? If congress allows us (no money in M&S this year). Scott Klasky (PPPL)