RTVR - a flexible Java library for interactive volume rendering

This paper presents several distinguishing design features of RTVR -- a Java-based library for interactive volume rendering. We describe, how the careful design of data structures, in our case based on voxel enumeration, and an intelligent use of lookup tables enable interactive volume rendering even on low-end PC hardware. By assigning voxels to distinct objects within the volume and by using an individual setup and combination of lookup tables for each object, object-aware rendering can be performed: different transfer functions, shading models and compositing modes (MIP, DVR) can be mixed within a single scene, while still providing rendering results in real-time

Studying basin bifurcations in nonlinear triopoly games by using 3D visualization

We consider three-dimensional discrete dynamical system, obtained by the iteration of a noninvertible map of , which simulates the time evolution of an oligopoly game with three competing firms. The model is characterized by the presence of several coexisting stable equilibria, each with its own basin of attraction. In this paper we face the question of the delimitation of the basins and the detection of the global bifurcations that cause the creation of non-connected basins. This requires a study of the global properties of the 3dimensional noninvertible map by the method of critical sets, based on the determination of the contact bifurcations through a systematic computer-assisted study. This requires the visualization of surfaces (the critical surfaces and the basins' boundaries) which sometimes are nested one inside the other. Enhanced graphical methods, based on two-level volume rendering, are employed in order to modulate the opacity of outer objects so that the contacts between the basins' boundaries and critical surfaces can be visualized. This is obtained through the realization of ad-hoc routines, which allow interactive 3D visualization. Key words: Dynamic Games, Discrete Dynamical Systems, noninvertible maps, Computer Graphics, Volume Rendering.

Bringing Your Visualization Application to the Internet

The Internet has a growing importance as a medium for presenting visualization and offering visualization tools. Due to strong variations in the quality of avaliable resources it is extremely difficult to design visualization systems including the Internet, which are capable of interactively visualizing user data. In this paper we identify requirements for a distributed visualization system to interactively visualize user data. As a possible solution to the identified problems we present a model for a visualization pipeline capable of fulfilling these requirements. Finally a proof-of-concept implementation of our ideas into Net Phase Plane, a visualization tool for dynamical systems, is discussed. keywords: visualization over the Internet, dynamical systems, computational steering, interactive visualization 1 Introduction The evolution of the world wide web based on the Internet was one of the most impressing developments in information technology during the past few years. Within a ..

Advanced High-Quality Maximum Intensity Projection for Volume Visualization

Maximum Intensity Projection (MIP) is a volume rendering technique which is used to extract high-intensity structures from volumetric data. At each pixel the highest data value encountered along the corresponding viewing ray is determined. MIP is commonly used to extract vascular structures from medical MRI data sets (angiography) . Due to lack of depth information in MIP images, animation of the viewpoint is frequently used for viewing. Although interactive MIP algorithms exist, the quality of the results is moderate. The generation of high-quality MIP animation loops is computationally expensive with rendering times of several seconds per frame. In this paper we present a fast algorithm for high-quality MIP. Cells of the data set which will never contribute to a MIP due to their neighborhood are removed during a preprocessing step. The remaining cells are stored in a way which improves cache coherency independent of the viewing direction and minimizes the number of required maximum e..

Fast and Flexible Iso-Surfacing for Virtual

Virtual endoscopy is an important tool for physicists, that can help them planning a real endoscopic examination or serve as a navigation aid during a physical endoscopy process. One of the strengths of virtual endoscopy is that not only the investigated organ can be displayed, but also surrounding objects like bones, blood vessels, or a tumor. This paper introduces a new visualization algorithm, which performs well visualizing the surface of the investigated organ, as well as outer structures, while keeping image quality and flexibility at a high level. Also, the preprocessing phase, in which objects of interest are chosen and segmented, is covered.