bvh-tree

A Bounding Volume Hierarchy data structure written in javascript, for spatial indexing of large triangle meshes. Enables fast intersection of rays with a triangle mesh.

Demo

ray-mesh intersection

Usage

Construct a BVH from a list of triangles

var triangle0 = [
  {x: 0.0, y: 0.0, z: 0.0},
  {x: 1000.0, y: 0.0, z: 0.0},
  {x:1000.0, y:1000.0, z:0.0}
];

var triangle1 = [
  {x: 0.0, y: 0.0, z: 0.0},
  {x: 2000.0, y: 0.0, z: 0.0},
  {x:2000.0, y:1000.0, z:0.0}
];

// the maximum number of triangles that can fit in a node before splitting it.
var maxTrianglesPerNode = 7; 

var bvh = new bvhtree.BVH([triangle0, triangle1], maxTrianglesPerNode);

Intersect a ray with the BVH

// origin point of the ray
var rayOrigin = {x: 1500.0, y: 3.0, z:1000};

// direction of the ray. should be normalized to unit length
var rayDirection = {x: 0, y:0, z:-1};

// if 'true', only intersections with front-faces of the mesh will be performed
var backfaceCulling = true;

var intersectionResult = bvh.intersectRay(rayOrigin, rayDirection, backfaceCulling);

intersectsRay() returns an array of intersection result objects, one for each triangle that intersected the ray. Each object contains the following properties:

triangle the triangle which the ray intersected
triangleIndex the position of the interescting triangle in the input triangle array provided to the BVH constructor.
intersectionPoint the interesection point of the ray on the triangle.

benraziel/bvh-tree

bvh-tree

Demo

Usage

Construct a BVH from a list of triangles

Intersect a ray with the BVH

License