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A Particle System for Interactive Visualization of 3D Flows
Jens Krüger,
Peter Kipfer,
Polina Kondratieva,
Rüdiger Westermann
Computer Graphics and Visualization Group,Technical University Munich, Germany
Background
We present a particle system for interactive visualization
of steady 3D flow fields on uniform grids. For the
amount of particles we target, particle integration needs to be
accelerated and the transfer of these sets for rendering must
be avoided. To fulfill these requirements, we exploit features of
recent graphics accelerators to advect particles in the graphics
processing unit (GPU), saving particle positions in graphics
memory, and then sending these positions through the GPU
again to obtain images in the frame buffer. This approach allows
for interactive streaming and rendering of millions of particles,
and it enables virtual exploration of high resolution fields in a
way similar to real-world experiments. The ability to display the
dynamics of large particle sets using visualization options like
shaded points or oriented texture splats provides an effective
means for visual flow analysis that is far beyond existing solutions.
For each particle, flow quantities like vorticity magnitude and Lambda2
are computed and displayed. Built upon a previously published
GPU implementation of a sorting network, visibility sorting of
transparent particles is implemented. To provide additional visual
cues, the GPU constructs and displays visualization geometry like
particle lines and stream ribbons.
The images above show the screenshots from the proposed particle system.
In the left image a collection of different visualization modes and modalities for a 3D
Navier – Stokes simulation is seen.
The right image shows a screenshot of the engine with some of the UI controls enabled to
give an idea of the “look and feel” of the proposed system.
The logo on top of this page shows the flow transition in a boundary layer is visualized. Red(green)
depicts lambda2 values less(greater) than zero. Transparency is fading out with increasing
lambda2 magnitude. Using 250K particles, the particle probe can be positioned interactively
at 30 fps.
All images can be enlarged by clicking onto them.
Associated publications
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