Motion visualization in large particle simulations

Abstract

Figure 1. We present a novel space-time hierarchy for large particle sets, which allows for the analysis of formation processes in astrophysical particle simulations, such as the merging of particles into clusters (middle image). Our approach can show the motion of mass at multiple levels of detail, and it allows classifying the motion dynamics based on directional information. ABSTRACTInteractive visualization of large particle sets is required to analyze the complicated structures and formation processes in astrophysical particle simulations. While some research has been done on the development of visualization techniques for steady particle fields, only very few approaches have been proposed to interactively visualize large time-varying fields and their dynamics. Particle trajectories are known to visualize dynamic processes over time, but due to occlusion and visual cluttering such techniques have only been reported for very small particle sets so far. In this paper we present a novel technique to solve these problems, and we demonstrate the potential of our approach for the visual exploration of large astrophysical particle sequences. We present a new hierarchical space-time data structure for particle sets which allows for a scale-space analysis of trajectories in the simulated fields. In combination with visualization techniques that adapt to the respective scales, clusters of particles with homogeneous motion as well as separation and merging regions can be identified effectively. The additional use of mapping functions to modulate the color and size of trajectories allows emphasizing various particle properties like direction, speed, or particle-specific attributes like temperature. Furthermore, tracking of interactively selected particle subsets permits the user to focus on structures of interest.

Scale-Space Splatting: Reforming Spacetime for Cross-Scale Exploration of Integral Measures in Molecular Dynamics

“…Focusing on the trajectories, hierarchical particle grouping for large datasets has been done by Fraedrich et al [18]. Schirski et al [39] extract prominent trajectories from large particle data.…”

Vector Field Visualization of Advective‐Diffusive Flows

“…However, resampling can introduce artifacts in undersampled regions and increases computational complexity in case of unnecessary oversampling [SFBP09]. Pure advection has been visualized by directly rendering particle trajectories in combination with space-time hierarchical clustering to reduce visual clutter [FW12]. Vortex core lines have been visualized directly from SPH-data using Hermite splines to interpolate between particle positions in time [SFBP09].…”

Mass‐Dependent Integral Curves in Unsteady Vector Fields

“…Most flow visualization techniques rely on virtual mass‐less particles moving within the underlying flow field. A system for the interactive visualization of large particle sets, exploiting graphics hardware capabilities, is presented by Krüger et al [KKKW05] and another system to explore multi‐variate flow properties is presented by Fraedrich and Westermann [FW12]. In addition, GPU realizations for massive particle advection in steady and time‐dependent vector fields have been presented by Peterka et al [PRN*11], Kipfer et al [KSW04] and Hlawatsch et al [HSW11].…”