GL4D: A GPU-based Architecture for Interactive 4D Visualization

This paper describes GL4D, an interactive system for visualizing 2-manifolds and 3-manifolds embedded in four Euclidean dimensions and illuminated by 4D light sources. It is a tetrahedron-based rendering pipeline that projects geometry into volume images, an exact parallel to the conventional triangle-based rendering pipeline for 3D graphics. Novel features include GPU-based algorithms for real-time 4D occlusion handling and transparency compositing; we thus enable a previously impossible level of quality and interactivity for exploring lit 4D objects. The 4D tetrahedrons are stored in GPU memory as vertex buffer objects, and the vertex shader is used to perform per-vertex 4D modelview transformations and 4D-to-3D projection. The geometry shader extension is utilized to slice the projected tetrahedrons and rasterize the slices into individual 2D layers of voxel fragments. Finally, the fragment shader performs per-voxel operations such as lighting and alpha blending with previously comp...

• Type: Conference
• Year: 2009
• Where: VIS
• Authors: Alan Chu, Chi-Wing Fu, Andrew J. Hanson, Pheng-Ann Heng
• Keywords: Per-vertex 4D Modelview, Real-time 4D Depthbuffering, Real-time 4D Occlusion, VIS 2009, Visualization