The VolPack Volume Rendering Library

VolPack is a portable software library for volume rendering, written by Philippe Lacroute. Developed as part of our volume rendering research project, the library is based on a new family of fast volume rendering algorithms (see Philippe Lacroute and Marc Levoy , Fast Volume Rendering Using a Shear-Warp Factorization of the Viewing Transformation, Proceedings of SIGGRAPH94). The library comes with vprender, a demonstration volume rendering application based on the Tcl scripting language, the Tk widget set, and VolPack. The Volpack library and its source code are available for research and commercial use, free of charge, as described at the bottom of this web page.

VolPack Overview

VolPack is a software library for fast, high-quality volume rendering. The library has the following features:

Renders data sampled on a regular, three-dimensional grid.
Supports user-specified transfer functions for both opacity and color.
Provides a shading model with directional light sources, multiple material types with different reflective properties, depth cueing, and shadows.
Produces color (24 bits/pixel) or grayscale (8 bits/pixel) renderings, with or without an alpha channel.
Supports arbitrary affine view transformations.
Supports a flexible data format that allows an arbitrary C structure to be associated with each voxel.

The library is intended for use in C or C++ programs but may be useful with other programming languages. The current implementation does not support perspective projections or clipping planes. These features will be added in a future release.

The library does not use any specialized hardware and is therefore portable to most platforms, yet it achieves very fast rendering times. On an SGI Indigo workstation a 256^3 voxel volume can be rendered in about one second.

Joe Zadeh of Northwestern University has donated a port of Volpack to Windows. Click here for the software. We have not tested this port. Please address all questions about it to [email protected].

VolPack Software Distribution

The current release of VolPack is version 1.0beta3, which is a beta release. There are several independent pieces of the release which you can retrieve by clicking on the headings in the following list. These items and some additional information are available by clicking on the links below.

VolPack (1024K bytes compressed): Compressed tar file containing source code for the library routines. Save it as volpack-1.0b3.tar.Z and type "zcat volpack-1.0b3.tar.Z | tar xf -" to unpack the source (or if your Web browser automatically decompresses files then use cat instead of zcat). Look at the README file in the unpacked source for further installation instructions.
vprender (245K bytes compressed): Compressed tar file containing source code for the vprender application, a demonstration volume rendering program. Save it as vprender-2.0b.tar.Z and type "zcat vprender-2.0b.tar.Z | tar xf -" to unpack the source (or if your Web browser automatically decompresses files then use cat instead of zcat). Then look at the README file in the unpacked source for further installation instructions. Vprender requires the VolPack library and the Tcl/Tk command language libraries. The README file describes how to get Tcl/Tk if you do not already have it.

Issac Trotts ([email protected]) a programmer on the NIH Human Brain Project at UC Davis, has modified volpack to work on Mac OS 10.3. Here is a gzipped tar file and a list of the changes. We have not tested this modification; please direct all email to Issac.

VolPack Documentation

VolPack User's Guide

We welcome questions, suggestions, comments, and bug reports from users of VolPack or vprender. However, we do not guarantee timely responses to them. In particular, the developers have long since graduated and left Stanford. Email should be sent to:

volpack@graphics.stanford.edu

Some volume rendering datasets are available in the Stanford volume data archive.

Distribution notice

During the period 1995-2007, this software was covered by the Stanford Computer Graphics Laboratory's custom-written General Software License. This license is royalty-free, nonexclusive, and nontransferable. Click here to view its terms and conditions. In modification of these terms and conditions, users were permitted to distribute or sell derivatives of this software without accounting to Stanford or the developers, and without payment of royalties to Stanford or the developers. However, title and copyright to the software and documentation remained with Stanford, and users were required to acknowledge the contribution of Stanford in any derivatives, as detailed in the license.

For downloads beginning on August 23, 2007, this software is covered by a new General Software License, which is based on the BSD license.

Last update: 4 January 1995