BVH Construction and Traversal Library

Note: This is the 2nd version of this library. Check the v1 branch for the older, first version of this library.

This library is a small, standalone library for BVH construction and traversal. It is licensed under the MIT license.

(Scene by Blend Swap user MaTTeSr, available here, distributed under CC-BY 3.0)

Performance

Here is a comparison of this library with other alternatives (Embree, Fast-BVH, and nanort):

Features

Here is a list of features supported by this library (changes from v1 are indicated with [NEW]):

[NEW] C++20 interface using std::span instead of raw pointers,
Low-level API with direct access to various builders,
[NEW] High-level DefaultBuilder API which selects the best builder depending on the desired BVH quality level.
High-quality, single-threaded sweeping SAH builder,
Fast, medium-quality, single-threaded binned SAH builder inspired by "On Fast Construction of SAH-based Bounding Volume Hierarchies", by I. Wald,
Fast, high-quality, multithreaded mini-tree BVH builder inspired by "Rapid Bounding Volume Hierarchy Generation using Mini Trees", by P. Ganestam et al.,
Reinsertion optimizer based on "Parallel Reinsertion for Bounding Volume Hierarchy Optimization", by D. Meister and J. Bittner,
Fast and robust traversal algorithm using "Robust BVH Ray Traversal", by T. Ize.
Fast ray-triangle intersection algorithm based on "Fast, Minimum Storage Ray/Triangle Intersection", by T. Möller and B. Trumbore,
[NEW] Surface area traversal order heuristic for shadow rays based on "SATO: Surface Area Traversal Order for Shadow Ray Tracing", by J. Nah and D. Manocha,
Fast ray-sphere intersection routine,
[NEW] Serialization/deserialization interface,
[NEW] Variable amount of dimensions (e.g. 2D, 3D, 4D BVHs are supported) and different scalar types (e.g. float or double),
[NEW] Only depends on the standard library (parallelization uses a custom thread pool based on std::thread),
[NEW] C API for the high-level parts of the library is available.

Building

This library is header-only, and can be added as a CMake subproject by cloning or adding as this repository as submodule, for instance in <your-project>/contrib/bvh, and then adding this to <your-project>/CMakeLists.txt:

add_subdirectory(contrib/bvh)
target_link_library(my_project PUBLIC bvh)

If you want to build the examples, use:

mkdir build
cd build
cmake .. -DCMAKE_BUILD_TYPE=<Debug|Release> -DENABLE_TESTING=ON
cmake --build .

C API

The library can be used via a small set of high-level C bindings. These bindings are not enabled by default, but can be built by configuring CMake with -DBVH_BUILD_C_API=ON. Additionally, if the intent is to use the library in a pure C environment which does not have the C++ standard library as a dependency, it might be a good idea to statically the C++ standard library. That can be done by adding the flag -DBVH_STATIC_LINK_STDLIB_C_API=ON to the CMake command line.

Usage

The library contains several examples that are kept up-to-date with the API: