A small utility to convert OpenVDB files to the Mitsuba 2 volume format.
The converter uses a recursive CMake setup to compile OpenVDB and its dependencies. The repository should be cloned recursively, i.e.
git clone --recursive https://github.com/mitsuba-renderer/mitsuba2-vdb-converter.git
Then, the build process is the regular CMake process:
cd mitsuba2-vdb-converter
mkdir build
cd build
cmake ..
make -j
This should then build all the dependencies as well as the converter utility. The setup was tested on Arch Linux and macOS 10.14.
Currently, the usage is limited to extracting a single float grid from an OpenVDB file. In the simplest case, the converter can be used as
./convertvdb myvolumefile.vdb
The output is then written in the same path with the suffix .vol. If the OpenVDB file contains multiple grids, one of them can be selected:
./convertvdb myvolumefile.vdb gridName
To get a list of grids in a file, one can use the vdb_print program, which is part of OpenVDB. In this CMake setup, the vdb_print executable is built and written to a subfolder in build/ext_build.
As of December 2019, there is an issue with Homebrew's boost installation on MacOS. This can be fixed by following https://stackoverflow.com/a/55828190.