6,774 research outputs found
MovieMaker: A Parallel Movie-Making Software for Large Scale Simulations
We have developed a parallel rendering software for scientific visualization
of large-scale, three-dimensional, time development simulations. The goal of
this software, MovieMaker, is to generate a movie, or a series of visualization
images from totally one TB-scale data within one night (or less than 12 hours).
The isocontouring, volume rendering, and streamlines are implemented.
MovieMaker is a parallel program for the shared memory architecture with
dynamic load balancing and overlapped disk I/O.Comment: 3pages, 5figures, submitted to J. Plasma Physcs (special issue for
19th ICNSP
Vortices in simulations of solar surface convection
We report on the occurrence of small-scale vortices in simulations of the
convective solar surface. Using an eigenanalysis of the velocity gradient
tensor, we find the subset of high vorticity regions in which the plasma is
swirling. The swirling regions form an unsteady, tangled network of filaments
in the turbulent downflow lanes. Near-surface vertical vortices are underdense
and cause a local depression of the optical surface. They are potentially
observable as bright points in the dark intergranular lanes. Vortex features
typically exist for a few minutes, during which they are moved and twisted by
the motion of the ambient plasma. The bigger vortices found in the simulations
are possibly, but not necessarily, related to observations of granular-scale
spiraling pathlines in "cork animations" or feature tracking.Comment: 11 pages, 13 figures, accepted for publication in A&A, complementary
movies at http://www.mps.mpg.de/homes/moll/strudel/papermovies
Visualizing 2D Flows with Animated Arrow Plots
Flow fields are often represented by a set of static arrows to illustrate
scientific vulgarization, documentary film, meteorology, etc. This simple
schematic representation lets an observer intuitively interpret the main
properties of a flow: its orientation and velocity magnitude. We propose to
generate dynamic versions of such representations for 2D unsteady flow fields.
Our algorithm smoothly animates arrows along the flow while controlling their
density in the domain over time. Several strategies have been combined to lower
the unavoidable popping artifacts arising when arrows appear and disappear and
to achieve visually pleasing animations. Disturbing arrow rotations in low
velocity regions are also handled by continuously morphing arrow glyphs to
semi-transparent discs. To substantiate our method, we provide results for
synthetic and real velocity field datasets
Combined surface and volumetric occlusion shading
Journal ArticleIn this paper, a method for interactive direct volume rendering is proposed that computes ambient occlusion effects for visualizations that combine both volumetric and geometric primitives, specifically tube shaped geometric objects representing streamlines, magnetic field lines or DTI fiber tracts. The proposed algorithm extends the recently proposed Directional Occlusion Shading model to allow the rendering of those geometric shapes in combination with a context providing 3D volume, considering mutual occlusion between structures represented by a volume or geometry
Uncertain Flow Visualization using LIC
In this paper we look at the Line Integral Convolution method for flow visualization and ways in which this can be
applied to the visualization of two dimensional, steady flow fields in the presence of uncertainty. To achieve this,
we start by studying the method and reviewing the history of modifications other authors have made to it in order
to improve its efficiency or capabilities, and using these as a base for the visualization of uncertain flow fields.
Finally, we apply our methodology to a case study from the field of oceanography
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