INTRODUCTION TO VISUALIZATION Alan B Craig Ph D

INTRODUCTION TO VISUALIZATION Alan B. Craig, Ph. D. Materials from: Dr. Alan Shih, Dave Bock, and Alan Craig, plus all the researchers who provided examples National Center for Supercomputing Applications University of Illinois at Urbana-Champaign June 3, 2010 National Computational Science Alliance

What Is Visualization? ! • Visualization existed before the invention of computers • Representation of information allowing us to perceive such information visually Dr. Alan M. Shih National Computational Science Alliance

Early Representation • The Cave of Lascaux, France ~15, 000 years old - Tells a story National Computational Science Alliance

Planetary Orbits • • • Tenth century Inclinations of the planetary orbits as a function of time. Oldest known attempt to show changing values graphically. National Computational Science Alliance

1987 NSF Panel Initiative - Formal Definition • "Visualization is a method of computing. It transforms the symbolic into the geometric, enabling researchers to observe their simulations and computations. Visualization offers a method for seeing the unseen. It enriches the process of scientific discovery and fosters profound and unexpected insights. ” • Richard Hamming: "The purpose of computing is insight, not numbers. " • Goal of visualization - leverage existing scientific methods by providing new scientific insight through visual methods. National Computational Science Alliance

Why do we do it? • Because we NEED to. . . National Computational Science Alliance

Purpose of Visualization • Self study / analysis – interactive exploration – gain understanding • Between Peers – Probing inside the problem domain – Analyzing data – Communicating with peers • Presentation to General Public – Overall visualization – Presentation of data – Communicating with general audience National Computational Science Alliance

Data Sources • Computational Sciences – Computational Fluid Dynamics – Computational Structured Mechanics – Computational Chemistry – Computational …. . • Observed Data – Wind Tunnels – Field Observations – Space Probes Dr. Alan M. Shih National Computational Science Alliance

What is Visualization • Choice of appropriate representation National Computational Science Alliance

Computational Sciences • We can realize, without physical prototypes – the performance of a design – the possible outcome of a scenario – the physical details that we did not know or notice • Benefits – Reduces development cost – Reduces development time – Reduces development risk Dr. Alan M. Shih National Computational Science Alliance

Computational Sciences • Computers brought about the ability to collect, create, and store more information • Is a process of simulating a relevant subset of the laws of nature through a set of equations • Yields a set of numeric solutions -Numbers, LOTS of them • May not be able to see, much less interpret, all of the results. Dr. Alan M. Shih National Computational Science Alliance

Visualization of Data • Try to envision the domain in your mind Dr. Alan M. Shih National Computational Science Alliance

Visualization of Data • But, with some modifications to the images. . . Dr. Alan M. Shih National Computational Science Alliance

Visualization of Data • Interpolated vs. Non-interpolated Dr. Alan M. Shih National Computational Science Alliance

Interactive or Batch? • Interactive Visualization – Allows the Ability to Control in Real-Time – Limits the Amount of Data to Be Visualized. – Useful for Analysis and Exploration • Batch Visualization – High-Quality, Complex Representation – No Control in Real Time. – Useful for Presentation, Communication, high complexity National Computational Science Alliance

The Visualization Pipeline • • • Data (simulated or observed) Filter Map to geometry Viewing Attributes Object Attributes Render Display Record Loop to appropriate step. . . National Computational Science Alliance

Computer Art and Scientific Visualization Cox, Donna; Patterson, Robert; Bargar, Robin; Daab, Fred; Moore, Michael; Moorman, Jan; Waegner, Chris; Erickson, Christian; Swing, Chris; Conrad, Renee; Knocke, Joel; Jordan, Robert; Brandys, Mike; Fossum, Barbara; Colby, Don; Mc. Neil, Mike; Bajuk, Mark; Arrott, Matthew; Swanson, Amy Researchers Cerco, Carl; Noel, Mark; CEWES Visualizaiton Stein, Robert; Shih, Alan; NCSA Dr. Alan M. Shih National Computational Science Alliance

Qualitative vs. Quantitative National Computational Science Alliance

A Wonderful Example National Computational Science Alliance

Static vs. Time Varying National Computational Science Alliance

Static vs. Time-Varying Data • Static – At an particular instance of time – Particular Point of View, etc. • Time-Varying Animation – Evolving along the time line – Dynamic Data or Point of View National Computational Science Alliance

Representational Techniques • Realistic • Abstract Researchers Visualization Cooper, David; Caterpillar Inc. Bajuk, Mark; NCSA , 1991 Researchers Cohen, Josef Visualization Cox, Donna, NCSA; Ellson, Rich; Olano, Marc, Eastman Kodak: Dr. Alan M. Shih National Computational Science Alliance

Representation Techniques Texture Mapping Visualization Stein, Robert, Baker, Polly, NCSA, ongoing Sponsored by ARL Dr. Alan M. Shih National Computational Science Alliance

Representation Techniques • Ball & Stick • Contour Researchers Herron, David, Eli Lilly & Co. Visualization Thingvold, Jeffrey A. ; Sherman, William; NCSA , 1991 Researchers Treutlein, Herbert; Schulten, Klaus; Physics Department Technical University of Munich Visualization Arrott, Matthew; NCSA, 1987 Researcher Taylor, Lafe Visualization Shih, Alan, MSU, 1993 Dr. Alan M. Shih National Computational Science Alliance

Representation Techniques • False Color • Height/Deformation Researchers Kovacic, David A. , Romme, William H. , Despain, Don G. Visualization Craig, Alan; NCSA, 1990 Researchers and visualization Haber, Bob; Lee, Hae-Sung; Koh, Hyun; NCSA, 1989 Dr. Alan M. Shih National Computational Science Alliance

Representation Techniques • Particulate/ Trace • Iso-surfaces Researchers Wilhelmson, Robert; Brooks, Harold; Jewett, Brian; Shaw, Crystal; Wicker, Louis; Department of Atmospheric Science and NCSA Visualization Arrott, Matthew; Bajuk, Mark; Thingvold, Jeffrey; Yost, Jeffery; Bushell, Colleen; Brady, Dan; Patterson, Bob Produced by the Visualization Services and Development Group, NCSA Dr. Alan M. Shih National Computational Science Alliance

Representation Techniques Data from Aerodynamics and Acoustics of Rotorcraft, W. J. Mc. Croskey, Principal Investigator Animation: FAST Particle Traces: UFAT Dr. Alan M. Shih National Computational Science Alliance

Scientific Visualization Damage Structure Researcher Namburu, Raju, CEWES Visualization Boch, David; Heiland, Randy; Baker, Polly; NCSA Stephens, Mike; CEWES Dr. Alan M. Shih National Computational Science Alliance

Scientific Visualization Damage Structure -- Animation Researcher Namburu, Raju, CEWES Visualization Boch, David; Heiland, Randy; Baker, Polly; NCSA Stephens, Mike; CEWES National Computational Science Alliance

Beyond Visual • Virtual Reality Environment – Immersa. Desk – Cave – Fully immersive sphere • Haptic Devices • Senses of hearing and smelling Dr. Alan M. Shih National Computational Science Alliance

Challenging Issues in Sci. Vis • Visualization of Large Data Sets – How to deal with exabytes of data? • Remote Visualization – What is the best way to visualize large data sets on remote mainframe? • Interactive Computation – How to monitor and steer ongoing simulations? • Representation Techniques – How to represent the data that shows more information and shows it more clearly and accurately? • Immersive Technologies Dr. Alan M. Shih National Computational Science Alliance

Summary • The advent of computer capacity and power push the envelope of computational sciences and scientific visualization (Sci. Vis) • Sci. Vis has revolutionized the way we do sciences • Sci. Vis provides scientists a process to probe into enormously large data sets, perceive incredible details of the domain, and discover unexpected insights. • Challenging issues in Sci. Vis evolve, but we will continue to face them, solve the problems, and face future challenges. Dr. Alan M. Shih National Computational Science Alliance

Visualization Tools National Computational Science Alliance

Visualization Tools Dr. Alan M. Shih National Computational Science Alliance

Layers of Information Dr. Alan M. Shih National Computational Science Alliance

Contour Surface & Volume Visualization Dr. Alan M. Shih National Computational Science Alliance

Composite Representation Dr. Alan M. Shih National Computational Science Alliance

Stereo Visualization • Red-Blue Glasses – Lost color • Shutter Glasses – 60 Hz – Synchronized with projected images • Polarized Glasses – Linear (Horizontal/Vertical) – Circular (CW/CCW) – Synchronized with projected images Dr. Alan M. Shih National Computational Science Alliance

Red-Blue Stereo Visualization Dr. Alan M. Shih National Computational Science Alliance

Animations Dr. Alan M. Shih National Computational Science Alliance