OpenVDB AX is an open source C++ library that provides a powerful and easy way of interacting with OpenVDB point and volume data. This exposes an expression language to allow fast, custom manipulation of point attributes and voxel values using a collection of mathematical functions. Expressions are quickly JIT-compiled and to offer great performance that in many cases rival custom C++ operators. It is developed and maintained by DNEG Visual Effects, providing a flexible and portable way to work with OpenVDB data.
This repository hosts the latest developments in the OpenVDB AX repository. This has been used in production at DNEG in various feature films yet remains a work-in-progress and such may be quite volatile. That is, both API and ABI may be subject to change so development using more niche features and lower-level components of the library (close to the LLVM component) should be approached with caution. However, use of the library and AX language (i.e. through the provided vdb_ax binary and Houdini OpenVDB AX SOP) is encouraged and future developments will focus on extending the language further to offer a wider range of functionality.
OpenVDB AX is released under the Mozilla Public License Version 2.0, which is a free, open source, and detailed software license developed and maintained by the Mozilla Foundation. It is a hybrid of the modified BSD license and the GNU General Public License (GPL) that seeks to balance the concerns of proprietary and open source developers. For more information see LICENSE.
This library uses doxygen for creating its documentation. Following the instructions laid out in INSTALL/BuildingWithCMake, with the required dependencies this can be generated by calling the following command make doc in the root directory of the library folder. This documentation currently includes both developer and user documentation including language examples, syntax and list of available functions.
Following building and installing the library as in INSTALL or BuildingWithCMake. If you have chosen to build the vdb_ax binary, this should be available from the install folder and can be accessed from the command line. Alternatively, using the OpenVDB AX Houdini SOP you will be able to modify OpenVDB data interactively within Houdini.