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Higher Dimensional Vector Field Visualization: A Survey
Zhenmin Peng, Robert S. Laramee
Department of Computer ScienceSwansea University, Wales UK
Email: {cszp, r.s.laramee}@swansea.ac.uk
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Overview
IntroductionIntroduction DimensionsDimensions ClassificationClassification
• Direct Flow VisualizationDirect Flow Visualization• Vector-field ClusteringVector-field Clustering• Texture-based TechniquesTexture-based Techniques• Geometric TechniquesGeometric Techniques
ConclusionConclusion
Streamsurface visualization of smokes [MLZ09]Streamsurface visualization of smokes [MLZ09]
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IntroductionWhat’s Vector Field Visualization?What’s Vector Field Visualization? A sub-branch of scientific visualizationA sub-branch of scientific visualization
Depiction of magnitude + direction (as opposed to scalar field vis)Depiction of magnitude + direction (as opposed to scalar field vis)
Various applications in our daily life: automotive simulation, Various applications in our daily life: automotive simulation,
aerodynamics, turbo machinery, meteorology, oceanography, aerodynamics, turbo machinery, meteorology, oceanography,
medical visualizationmedical visualization
Visualization of flow around a car [Garth’08]Visualization of flow around a car [Garth’08]Arrows showing the wind Arrows showing the wind
direction and magnitude [Turk’96]direction and magnitude [Turk’96]
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Introduction
What’s the motivation of this paper?What’s the motivation of this paper? The challenge of 2D flow visualization is virtually solvedThe challenge of 2D flow visualization is virtually solved
Higher dimensional (2.5D & 3D) flow visualization is still facing Higher dimensional (2.5D & 3D) flow visualization is still facing
many challenges like: coping with large, time-dependent data many challenges like: coping with large, time-dependent data
sets, perceptual difficulties and so onsets, perceptual difficulties and so on
Focus on the most recent developments in higher dimensional Focus on the most recent developments in higher dimensional
flow visualization techniquesflow visualization techniques
Highlighting both solved and unsolved problemsHighlighting both solved and unsolved problems
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Dimensions
Spatial dimension:Spatial dimension: 2D (planar flow)2D (planar flow)
2.5D (boundary flow, flow on surface)2.5D (boundary flow, flow on surface)
3D (real-world flow, volumetric flow)3D (real-world flow, volumetric flow)
Temporal dimension:Temporal dimension: Steady flow - one time step (or instantaneous or static flow)Steady flow - one time step (or instantaneous or static flow)
Time-dependent flow - multiple time steps (or unsteady or Time-dependent flow - multiple time steps (or unsteady or
transient, real-world)transient, real-world)
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Classification Direct: Direct: overview of vector field, minimal overview of vector field, minimal
computation, e.g. glyphs, colour mappingcomputation, e.g. glyphs, colour mapping
Feature-based:Feature-based: provides suggestive provides suggestive
visualization by extracting subsets of data before visualization by extracting subsets of data before
visualization, e.g. vector field clusteringvisualization, e.g. vector field clustering
Texture-based:Texture-based: covers domain with a convolved covers domain with a convolved
texture, e.g., Spot Noise, LIC, ISA, IBFV(S)texture, e.g., Spot Noise, LIC, ISA, IBFV(S)
Geometric:Geometric: coherent representation, integration- coherent representation, integration-
based geometric techniques, e.g. streamlinesbased geometric techniques, e.g. streamlines
Vector field clusteringVector field clustering
Hedgehog Hedgehog
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Survey Overview
*Related previous work in 2D is indicated by sub-scripts*Related previous work in 2D is indicated by sub-scripts
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Direct Flow VisualizationVector Glyphs for Surfaces: A Fast and Simple Glyph PlacementVector Glyphs for Surfaces: A Fast and Simple Glyph PlacementAlgorithm for Adaptive Resolution MeshesAlgorithm for Adaptive Resolution Meshes ( (Peng and Laramee ‘08Peng and Laramee ‘08))
Dimensions:Dimensions: 2.5D, Steady 2.5D, Steady
Predecessor:Predecessor: 2D method of [Lar03] 2D method of [Lar03]
Concept:Concept: a simple, fast, and general a simple, fast, and general
glyph placement for surfacesglyph placement for surfaces
Implementation:Implementation:
Project vector field to image planeProject vector field to image plane
Reconstruction & glyph placement Reconstruction & glyph placement
are performed in image spaceare performed in image space
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Vector Field Clustering VisualizationSimplified Representation of Vector FieldsSimplified Representation of Vector Fields ( (Telea and van Wijk ‘99Telea and van Wijk ‘99))
Dimensions:Dimensions: 3D, Steady 3D, Steady
Concept:Concept: a hierarchical clustering a hierarchical clustering
based method which presents a based method which presents a
suggestive overview of vector fieldssuggestive overview of vector fields
Implementation:Implementation:
Bottom-up fashion Bottom-up fashion
Merger driven by similarity error Merger driven by similarity error
metricmetric
InteractionInteraction
Simplification of 3D flow [TvW99] Simplification of 3D flow [TvW99]
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Texture-based VisualizationImage Space Based Visualization of Unsteady Flow on SurfacesImage Space Based Visualization of Unsteady Flow on Surfaces((Laramee et al. ‘03Laramee et al. ‘03))
Dimensions:Dimensions: 2.5D, Unsteady 2.5D, Unsteady Predecessor:Predecessor: IBFV (2D) [vW02] IBFV (2D) [vW02] Concept:Concept: dense and coherent dense and coherent
representations for unsteady flow on representations for unsteady flow on surfacessurfaces
Implementation:Implementation: Project vector field to image space Project vector field to image space Advection mesh is distorted Advection mesh is distorted
according to pathlinesaccording to pathlines Texture is distorted and attached Texture is distorted and attached
based on the distorted meshbased on the distorted mesh Blend noise in image spaceBlend noise in image space
Gas Engine Simulation [LJH03] Gas Engine Simulation [LJH03]
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Texture-based VisualizationHigh-Quality and Interactive Animations of 3D High-Quality and Interactive Animations of 3D Time-Varying Vector Fields Time-Varying Vector Fields ((Helgeland & Elboth Helgeland & Elboth ‘06‘06))
Dimensions:Dimensions: 3D, Unsteady 3D, Unsteady Predecessor:Predecessor: DLIC (2D) [Sun03] DLIC (2D) [Sun03] Concept:Concept: efficiently and interactively efficiently and interactively
visualize unsteady 3D flow in sparse visualize unsteady 3D flow in sparse fashionfashion
Implementation:Implementation: Particles are evenly distributed to Particles are evenly distributed to
obtain pathlinesobtain pathlines A novel particle advection strategy A novel particle advection strategy
maintains the coherent particle density maintains the coherent particle density at each time stepat each time step
3D texture generated for each time step3D texture generated for each time step interactioninteraction
visualization of the hurricane velocity field visualization of the hurricane velocity field [HE06] [HE06]
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Geometric-based VisualizationEvenly-Spaced Streamlines for Surfaces: An Image-Based ApproachEvenly-Spaced Streamlines for Surfaces: An Image-Based Approach((Spencer et al. '09Spencer et al. '09))
Dimensions:Dimensions: 2.5D, Steady 2.5D, Steady Predecessor:Predecessor: Jobard and Lefer’s 2D Jobard and Lefer’s 2D
method [JL97]method [JL97] Concept:Concept: general streamline general streamline
placement for surfacesplacement for surfaces Implementation:Implementation:
Project vector field to image Project vector field to image space space
Perform streamline integration Perform streamline integration in image spacein image space
InteractionsInteractionsVisualization of flow at the surface Visualization of flow at the surface
of a cooling jacket.[SLCZ09] of a cooling jacket.[SLCZ09]
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Geometric-based VisualizationSmoke Surfaces: An Interactive Flow Visualization TechniqueSmoke Surfaces: An Interactive Flow Visualization Technique
Inspired by Real-World Flow Experiments (Inspired by Real-World Flow Experiments (Von Funck et al. '08Von Funck et al. '08))
Dimensions:Dimensions: 3D, Unsteady 3D, Unsteady Concept:Concept: efficient representation of efficient representation of
smoke surfaces in 3D spacesmoke surfaces in 3D space Implementation:Implementation:
Semi-transparent streak surfaces Semi-transparent streak surfaces Coupling the opacity to area, Coupling the opacity to area,
shapes and curvaturesshapes and curvatures With a fixed topology and With a fixed topology and
connectivityconnectivity Interactive explorationInteractive exploration
[vFWTS08] [vFWTS08]
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Conclusion
Dimensions and classifications.Dimensions and classifications. Up-to-date overview of the vector field visualization in higher Up-to-date overview of the vector field visualization in higher
dimensions.dimensions. Highlighting both mature areas and immature areas in higher Highlighting both mature areas and immature areas in higher
dimensional flow visualization.dimensional flow visualization.
Future Work:Future Work: Time-dependent flow datasets Time-dependent flow datasets Visual complexity and occlusionVisual complexity and occlusion Automatic or semi-automatic selection and simplification Automatic or semi-automatic selection and simplification approaches for visualizationapproaches for visualization
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Classification
*Related previous work in 2D is indicated by sub-scripts*Related previous work in 2D is indicated by sub-scripts
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Acknowledgments
Thanks to:Thanks to:
TPCG 2009 TPCG 2009 EPSRCEPSRC Visual and Interactive ComputingVisual and Interactive Computing Edward GrundyEdward Grundy
Paper and related animations available at:Paper and related animations available at:
http://cs.swan.ac.uk/~cszp/http://cs.swan.ac.uk/~cszp/
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Thank you for your attention.Thank you for your attention.
Questions or Suggestions?Questions or Suggestions?