doppler speckles – a multi-purpose vectoreld visualization technique for arbitrary meshes
DESCRIPTION
Doppler Speckles – A Multi-Purpose Vectoreld Visualization Technique for Arbitrary Meshes. Werner Benger 1 and Georg Ritter 3 and Simon Su 4 and Dimitris E. Nikitopoulos 2 and Eamonn Walker 2 and Sumanta Acharya 2 and Somnath Roy 2 and Farid Harhad 1 and Wolfgang Kapferer 3 - PowerPoint PPT PresentationTRANSCRIPT
DOPPLER SPECKLES –A MULTI-PURPOSE
VECTORELDVISUALIZATION TECHNIQUE
FOR ARBITRARY MESHESWerner Benger1 and Georg Ritter3 and Simon Su4 and
Dimitris E. Nikitopoulos2 and Eamonn Walker2 andSumanta Acharya2 and Somnath Roy2 and
Farid Harhad1 and Wolfgang Kapferer3
1Center for Computation and Technology, Louisiana State University, USA2Department for Mechanical Engineering, Louisiana State University, USA
3Institute for Astro- and Particle Physics, University of Innsbruck4Princeton Institute for Computational Science and Engineering
Outline
The Problem
The Approach
Application Examples
The ProblemVisualizing Vectors
in 3D & 4D
The Approach Splatting Technique: Drawing of Gaussian
spots as billboard per vertex Used for Volume Rendering of
Unstructured Meshes
Gaussian splats in view plane – Efficiently done via OpenGL Point Sprites
Vector Speckle Elongate along direction of vector in a
field1. Stretch
2. Orient
3. Offset
Vector Speckle - Stretch Stretch according to Vector Magnitude
Freedom in various scaling factors and mappings (like vector arrows)
Compute Projection of Vector in View Plane
View-dependent shape – requires GL fragment shader
Vector Speckle - Orientation
View Plane
Vector Speckle - OffsetFree parameter to allow animation of
display element T=0.0
T=0.2
T=0.5
Doppler Effect Physical Effect: movement of wave-
emitting objects influences observed frequency
Known as sound of passing street cars: Movement to observer increases frequency Movement from observer decreases frequency
Light: Color change of moving objects Approaching - higher frequency – blueshift Escaping - lower frequency - redshift
Application Examples1. Couette Flow (Analytic Vector field)
2. Microchannel Droplet (Uniform Grid)
3. Stirtank Fluid (Curvilinear Multiblock)
4. Galaxy Evolution (Particle System)
Couette FlowVECTOR ARROWS DOPPLER SPECKLES
Couette FlowSTREAMLINES DOPPLER SPECKLES
Couette FlowDOWN VIEW UP VIEW
Microchannel DropletFRONT VIEW BACK VIEW
Streamlines EnhancedSTREAMLINES SPECKLES ON
STREAMLINES
Streamlines EnhancedSTREAMLINES SPECKLES ON
STREAMLINES
Stir Tank 2088 Curvilinear Blocks
SIDE VIEW UP VIEW
Evolving Galaxies 16 Million particles,
each representing one galaxy
Cosmological evolution over several billion years
300GB of raw data Velocity given for
each galaxy
Evolving Galaxies
Evolving Galaxies
Evolving Galaxies
Availability Algorithms implemented and available in
Vish – Visualization Shell Freely available for academic usage
Code development management: http://sciviz.cct.lsu.edu/projects/vish
Available via SVN in source code for registered users at http://vish.origo.ethz.ch/