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We review software for exploring biological evolution from a fun and educational perspective. Our goal is to provide a background explanation of the methods used, terminology, and user experience, and learning outcomes of desktop and mobile evolutionary simulators. Freeware and commercial programs are detailed, with a discussion of how certain software packages can be used in introducing evolutionary theory. [ABSTRACT FROM AUTHOR]

We present an up-to-date survey on physically-based smoke simulation. Physically-based method becomes predominant in smoke simulation in computer graphics community. It prevails over traditional methods for its plausible visual effect. Significant results have been carried out over past two decades. We give a latest overview of state-of-the-art of smoke simulation and also compare various techniques according to their characteristics. We discuss several issues in terms of computational efficiency, numerical stability, numerical dissipation, and runtime performance. A number of open challenging problems are also addressed for further exploration. [ABSTRACT FROM AUTHOR]

Physically based fluid simulations usually require expensive computation cost for creating realistic animations. We present a technique that allows the user to create various fluid animations from an input fluid animation sequence, without the need for repeatedly performing simulations. Our system allows the user to deform the flow field in order to edit the overall fluid behavior. In order to maintain plausible physical behavior, we ensure the incompressibility to guarantee the mass conservation. We use a vector potential for representing the flow fields to realize such incompressibility-preserving deformations. Our method first computes (time-varying) vector potentials from the input velocity field sequence. Then, the user deforms the vector potential, and the system computes the deformed velocity field by taking the curl operator on the vector potential. The incompressibility is thus obtained by construction. We show various examples to demonstrate the usefulness of our method. [ABSTRACT FROM AUTHOR]

Recently, many techniques using computational fluid dynamics have been proposed for the simulation of natural phenomena such as smoke and fire. Traditionally, a single grid is used for computing the motion of fluids. When an object interacts with a fluid, the resolution of the grid must be sufficiently high because the shape of the object is represented by a shape sampled at the grid points. This increases the number of grid points that are required, and hence the computational cost is increased. To address this problem, we propose a method using multiple grids that overlap with each other. In addition to a large single grid (a global grid) that covers the whole of the simulation space, separate grids (local grids) are generated that surround each object. The resolution of a local grid is higher than that of the global grid. The local grids move according to the motion of the objects. Therefore, the process of resampling the shape of the object is unnecessary when the object moves. To accelerate the computation, appropriate resolutions are adaptively-determined for the local grids according to their distance from the viewpoint. Furthermore, since we use regular (orthogonal) lattices for the grids, the method is suitable for GPU implementation. This realizes the real-time simulation of interactions between objects and smoke. [ABSTRACT FROM AUTHOR]

Visual quality, low computational cost, and numerical stability are foremost goals in computer animation. An important ingredient in achieving these goals is the conservation of fundamental motion invariants. For example, rigid and deformable body simulation benefits greatly from the conservation of linear and angular momenta. In the case of fluids, however, none of the current techniques focuses on conserving invariants, and consequently, often introduce a visually disturbing numerical diffusion of vorticity. Just as important visually is the resolution of complex simulation domains. Doing so with regular (even if adaptive) grid techniques can be computationally delicate. In this article, we propose a novel technique for the simulation of fluid flows. It is designed to respect the defining differential properties, that is, the conservation of circulation along arbitrary loops as they are transported by the flow. Consequently, our method offers several new and desirable properties: Arbitrary simplicial meshes (triangles in 2D, tetrahedra in 3D) can be used to define the fluid domain; the computations involved in the update procedure are efficient due to discrete operators with small support; and it preserves discrete circulation, avoiding numerical diffusion of vorticity. [ABSTRACT FROM AUTHOR]

Abstract Rendering participating media is important for a number of domains, ranging from commercial applications (entertainment, virtual reality) to simulation systems (driving, flying, and space simulators) and safety analyses (driving conditions, sign visibility). This article surveys global illumination algorithms for environments including participating media. It reviews both appearance-based and physically-based media methods, including the single-scattering and the more general multiple-scattering techniques. The objective of the survey is the characterization of all these methods: identification of their base techniques, assumptions, limitations, and range of utilization. It concludes with some reflections about the suitability of the methods depending on the specific application involved, and possible future research lines. [ABSTRACT FROM AUTHOR]

Any modeling scheme for gaseous phenomena in graphics has to capture three aspects: the fuzzy geometry of the gas, the dynamics, characterized by the presence of vortices, and the interaction of light with the gaseous volume. We represent the gaseous volume as a particle system and apply Vortex Element Methods (VEM) to model the dynamics. A Lagrangian formulation that is gridless and hence ideal for unbounded flows is used. A gridless approach to ray tracing the particle systems is developed using particle maps. These maps are used to estimate densities within a gaseous volume analogous to the way volume photon maps are used to estimate radiance during Monte Carlo ray tracing. A technique is proposed to merge particle and volume photon maps to obtain an effective method for simulating multiple scattering in a dynamic inhomogeneous participating medium. Our method for modeling and rendering gaseous phenomena is conceptually simple and grid free. Particle maps play an effective role, as the nearest neighbor information obtained during the rendering phase is exploited during the dynamics computation. We preset results that demonstrate the effectiveness of our approach. Copyright © 2000 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Considers the Mars database visualization as an example of platform downsizing. Role of understanding human visual perception in the design of a visualization system; Derivation of the digital terrain model from the Viking orbital imagery; Suggestion of options for visualization hardware and software.

Presents a list of information resources about computer animation. "Real-Time Animation Playback on a Frame Store Display System," by B. Ackland and N. Weste, published in the journal "Computer Graphics"; "The Simulation of Space," by R. Armbrust, published in the journal "Computer Pictures"; "The Dynamics of Articulated Rigid Bodies for Purposes of Animal," by W. W. Armstrong and M. Green, published in the journal "The Visual Computer."

We propose a memory-based naming game (MBNG) model with two-state variables in full-connected networks, which is like some previous opinion propagation models. It is found that this model is deeply affected by the memory decision parameter, and then its dynamical behaviour can be partly analysed by using numerical simulation and analytical argument. We also report a modified MBNG model with the forgetting curve of Ebbinghaus in the memory. With deletion of one parameter in the MBNG model, it can converge to success rate S(t) = 1 and the average sum E(t) is decided by the size of network N. [ABSTRACT FROM AUTHOR]