TY - GEN A1 - Günther, Tobias A1 - Kuhn, Alexander A1 - Hege, Hans-Christian A1 - Gross, Markus A1 - Theisel, Holger T1 - Progressive Monte-Carlo Rendering of Atmospheric Flow Features Across Scales T2 - 69th Annual Meeting of the APS Division of Fluid Dynamics, Gallery of Fluid Motion, Nov 20-22, 2016, Portland, OR, USA. N2 - To improve existing weather prediction and reanalysis capabilities, high-resolution and multi-modal climate data becomes an increasingly important topic. The advent of increasingly dense numerical simulation of atmospheric phenomena, provides new means to better understand dynamic processes and to visualize structural flow patterns that remain hidden otherwise. In the presented illustrations we demonstrate an advanced technique to visualize multiple scales of dense flow fields and Lagrangian patterns therein, simulated by state-of-the-art simulation models for each scale. They provide a deeper insight into the structural differences and patterns that occur on each scale and highlight the complexity of flow phenomena in our atmosphere. Y1 - 2016 U6 - https://doi.org/10.1103/APS.DFD.2016.GFM.P0030 ER - TY - JOUR A1 - Günther, Tobias A1 - Kuhn, Alexander A1 - Hege, Hans-Christian A1 - Gross, Markus A1 - Theisel, Holger T1 - Progressive Monte Carlo rendering of atmospheric flow features across scales JF - Physical Review Fluids N2 - To improve existing weather prediction and reanalysis capabilities, high-resolution and multi-modal climate data becomes an increasingly important topic. The advent of increasingly dense numerical simulation of atmospheric phenomena, provides new means to better understand dynamic processes and to visualize structural flow patterns that remain hidden otherwise. In the presented illustrations we demonstrate an advanced technique to visualize multiple scales of dense flow fields and Lagrangian patterns therein, simulated by state-of-the-art simulation models for each scale. They provide a deeper insight into the structural differences and patterns that occur on each scale and highlight the complexity of flow phenomena in our atmosphere. This paper is associated with a poster winner of a 2016 APS/DFD Milton van Dyke Award for work presented at the DFD Gallery of Fluid Motion. The original poster is available from the Gallery of Fluid Motion, https://doi.org/10.1103/APS.DFD.2016.GFM.P0030 Y1 - 2017 U6 - https://doi.org/10.1103/PhysRevFluids.2.090502 VL - 2 SP - 09050-1 EP - 09050-3 ER - TY - CHAP A1 - Shi, Kuangyu A1 - Theisel, Holger A1 - Weinkauf, Tino A1 - Hauser, Helwig A1 - Hege, Hans-Christian A1 - Seidel, Hans-Peter T1 - Path line oriented topology for periodic 2D time-dependent vector fields T2 - Proc. Eurographics / IEEE VGTC Symposium on Visualization Y1 - 2006 SP - 139 EP - 146 CY - Lisbon, Portugal ER - TY - CHAP A1 - Shi, Kuangyu A1 - Theisel, Holger A1 - Hauser, Helwig A1 - Weinkauf, Tino A1 - Hege, Hans-Christian A1 - Seidel, Hans-Peter T1 - Path Line Attributes - an Information Visualization Approach to Analyzing the Dynamic Behavior of 3D Time-Dependent Flow Fields T2 - Topology-Based Methods in Visualization II Y1 - 2009 U6 - https://doi.org/10.1007/978-3-540-88606-8_6 SP - 75 EP - 88 PB - Springer CY - Berlin ER - TY - JOUR A1 - Günther, Tobias A1 - Kuhn, Alexander A1 - Hege, Hans-Christian A1 - Theisel, Holger T1 - MCFTLE: Monte Carlo Rendering of Finite-Time Lyapunov Exponent Fields JF - Computer Graphics Forum Y1 - 2016 U6 - https://doi.org/10.1111/cgf.12914 N1 - By mistake the fourth author Hans-Christian Hege has been ommitted in the journal publication VL - 35 IS - 3 SP - 381 EP - 390 ER - TY - GEN A1 - Günther, Tobias A1 - Kuhn, Alexander A1 - Hege, Hans-Christian A1 - Theisel, Holger T1 - MCFTLE: Monte Carlo Rendering of Finite-Time Lyapunov Exponent Fields N2 - Traditionally, Lagrangian fields such as finite-time Lyapunov exponents (FTLE) are precomputed on a discrete grid and are ray casted afterwards. This, however, introduces both grid discretization errors and sampling errors during ray marching. In this work, we apply a progressive, view-dependent Monte Carlo-based approach for the visualization of such Lagrangian fields in time-dependent flows. Our ap- proach avoids grid discretization and ray marching errors completely, is consistent, and has a low memory consumption. The system provides noisy previews that con- verge over time to an accurate high-quality visualization. Compared to traditional approaches, the proposed system avoids explicitly predefined fieldline seeding structures, and uses a Monte Carlo sampling strategy named Woodcock tracking to distribute samples along the view ray. An acceleration of this sampling strategy requires local upper bounds for the FTLE values, which we progressively acquire during the rendering. Our approach is tailored for high-quality visualizations of complex FTLE fields and is guaranteed to faithfully represent detailed ridge surface structures as indicators for Lagrangian coherent structures (LCS). We demonstrate the effectiveness of our approach by using a set of analytic test cases and real-world numerical simulations. T3 - ZIB-Report - 16-21 KW - Picture/Image Generation, Display algorithms, Three-Dimensional Graphics and Realism, Raytracing Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-59054 SN - 1438-0064 N1 - By mistake the fourth author Hans-Christian Hege has been ommitted in the journal publication ER - TY - CHAP A1 - Theisel, Holger A1 - Weinkauf, Tino A1 - Hege, Hans-Christian A1 - Seidel, Hans-Peter T1 - Grid-independent detection of closed stream lines in 2D vector fields T2 - Proc. Vision, Modeling and Visualization 2004 Y1 - 2004 SP - 421 EP - 428 CY - Stanford, U.S.A. ER - TY - CHAP A1 - Shi, Kuangyu A1 - Theisel, Holger A1 - Weinkauf, Tino A1 - Hege, Hans-Christian A1 - Seidel, Hans-Peter T1 - Finite-Time Transport Structures of Flow Fields T2 - Proc. IEEE Pacific Visualization 2008 Y1 - 2008 U6 - https://doi.org/10.1109/PACIFICVIS.2008.4475460 SP - 63 EP - 70 CY - Kyoto, Japan ER - TY - CHAP A1 - Weinkauf, Tino A1 - Sahner, Jan A1 - Günther, Bert A1 - Theisel, Holger A1 - Hege, Hans-Christian A1 - Thiele, Frank T1 - Feature-based Analysis of a Multi-Parameter Flow Simulation T2 - Proc. of 19th Simulation and Visualization Conference (SimVis 2008) Y1 - 2008 SP - 237 EP - 251 CY - Magdeburg, Germany ER - TY - CHAP A1 - Weinkauf, Tino A1 - Theisel, Holger A1 - Hege, Hans-Christian A1 - Seidel, Hans-Peter T1 - Feature Flow Fields in Out-of-Core Settings T2 - Topology-based Methods in Visualization Y1 - 2007 SP - 51 EP - 64 PB - Springer ER -