In this paper we present our research efforts towards a scalable volume rendering architecture for the real-time visualization of dynamically changing high-resolution datasets. Using a linearly skewed memory interleaving we were able to develop a parallel dataflow model that leads to local, fixed-bandwidth interconnections between processing elements. This parallel dataflow model differs from previous work in that it requires no global communication of data except at the pixel level. Using this dataflow model we are developing Cube-4, an architecture that is scalable to very high performances and allows for modular and extensible hardware implementations.

Volume rendering is a key technology in scientific visualization that lends itself to significant exploitable parallelism. The high computational demands of real-time volume rendering and the continued technological advances in the area of VLSI give impetus to the development of special-purpose volume rendering architectures. This paper presents and characterizes three recently developed volume rendering engines which are based on the ray-casting method. A taxonomy of the algorithmic variants of ray-casting and details of each ray-casting architecture are discussed. Then paper then compares the machine features and provides an outlook on future developments in the area of volume rendering hardware.

This paper describes a high-performance special-purpose system, Cube-3, for displaying and manipulating high-resolution volumetric datasets in real-time. A primary goal of Cube-3 is to render 512x512x512, 16-bit per voxel, datasets at about 30 frames per second. Cube-3 implements a ray-casting algorithm in a highly-parallel and pipelined architecture, using a 3D skewed volume memory, a modular fast bus, 2D skewed buffers, 3D interpolation and shading units, and a ray projection cone. Cube-3 will allow users to interactively visualize and investigate in real-time static (3D) and dynamic (4D) high-resolution volumetric datasets.

In this paper we present a technique for the interactive control and display of static and dynamic 3D datasets. We describe novel ways of tri-linear interpolation and gradient estimation for a real-time volume rendering system, using coherency between rays. We show simulation results that compare the proposed methods to traditional algorithms and present them in the context of Cube-3, a special-purpose architecture capable of rendering 512x512x512 16-bit per voxel datasets at over 20 frames per second.

This paper describes a high-performance special-purpose system, the Cube-3 machine, for displaying and manipulating high-resolution volumetric datasets in real-time. Cube-3 will allow scientists, engineers, and biomedical researchers to interactively visualize and investigate their static high-resolution sampled, simulated, or computed volumetric dataset. Furthermore, once acquisition devices or mechanisms are capable of acquiring a complete high-resolution dynamic dataset in real-time, Cube-3, tightly coupled with them, will be capable of delivering real-time 4D (spatial-temporal) volume visualization, a task currently not possible with present technologies.

We present a special architecture for arbitrary parallel projection for visualization of volumetric data. Using a ray-casting technique, parallel memory access, and pipelined processing of rays in a composition tree, we can achieve interactive rendering rates for a 512x512x512 dataset.