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use std::time::Duration;
use glam::*;
use obvhs::{
BvhBuildParams,
bvh2::builder::build_bvh2_from_tris,
ray::{Ray, RayHit},
test_util::geometry::{PLANE, icosphere},
triangle::Triangle,
};
fn main() {
// Build a scene with an icosphere and a plane
// BVH primitives do not need to be triangles, the BVH builder is only concerned with AABBs.
// (With the exception of optional precise triangle aabb splitting)
let mut tris: Vec<Triangle> = Vec::new();
tris.extend(icosphere(1));
tris.extend(PLANE);
// Build the BVH.
// build_bvh_from_tris is just a helper that can build from BvhBuildParams and the
// respective presets. Feel free to copy the contents of build_bvh_from_tris or build_bvh.
// They are very straightforward. If you don't want to use Triangles as the primitive, use
// build_bvh instead. build_cwbvh_from_tris just adds support for splitting tris.
let bvh = build_bvh2_from_tris(
&tris,
BvhBuildParams::medium_build(),
&mut Duration::default(),
);
// Create a new ray
let ray = Ray::new_inf(vec3a(0.1, 0.1, 4.0), vec3a(0.0, 0.0, -1.0));
// Traverse the BVH, finding the closest hit.
let mut ray_hit = RayHit::none();
if bvh.ray_traverse(ray, &mut ray_hit, |ray, id| {
// Use primitive_indices to look up the original primitive id.
// (Could reorder tris per bvh.primitive_indices to avoid this lookup, see cornell_box_cwbvh example)
tris[bvh.primitive_indices[id] as usize].intersect(ray)
}) {
println!(
"Hit Triangle {}",
bvh.primitive_indices[ray_hit.primitive_id as usize]
);
println!("Distance to hit: {}", ray_hit.t);
} else {
println!("Miss");
}
}