diff --git a/src/aabb.rs b/src/aabb.rs
index ef728e9f..c027d93e 100644
--- a/src/aabb.rs
+++ b/src/aabb.rs
@@ -13,6 +13,12 @@ pub struct Aabb {
 	pub max: glam::Vec3,
 }
 
+impl Default for Aabb {
+	fn default() -> Self {
+		Aabb::new()
+	}
+}
+
 impl Aabb {
 	const VERTEX_DATA: [glam::Vec3; 8] = [
 		glam::vec3(1., -1., -1.),
@@ -37,6 +43,13 @@ impl Aabb {
 		self.min=self.min.min(aabb.min);
 		self.max=self.max.max(aabb.max);
 	}
+	pub fn inflate(&mut self, hs:glam::Vec3){
+		self.min-=hs;
+		self.max+=hs;
+	}
+	pub fn intersects(&self,aabb:&Aabb)->bool{
+		(self.min.cmplt(aabb.max)&aabb.min.cmplt(self.max)).all()
+	}
 	pub fn normal(face:AabbFace) -> glam::Vec3 {
 		match face {
 			AabbFace::Right => glam::vec3(1.,0.,0.),
diff --git a/src/bvh.rs b/src/bvh.rs
index 62eadc9f..b79ecc0e 100644
--- a/src/bvh.rs
+++ b/src/bvh.rs
@@ -9,13 +9,26 @@ use crate::aabb::Aabb;
 //start with bisection into octrees because a bad bvh is still 1000x better than no bvh
 //sort the centerpoints on each axis (3 lists)
 //bv is put into octant based on whether it is upper or lower in each list
-
+#[derive(Default)]
 pub struct BvhNode{
 	children:Vec<Self>,
 	models:Vec<u32>,
 	aabb:Aabb,
 }
 
+impl BvhNode{
+	pub fn the_tester<F:FnMut(u32)>(&self,aabb:&Aabb,f:&mut F){
+		for &model in &self.models{
+			f(model);
+		}
+		for child in &self.children{
+			if aabb.intersects(&child.aabb){
+				child.the_tester(aabb,f);
+			}
+		}
+	}
+}
+
 pub fn generate_bvh(boxen:Vec<Aabb>)->BvhNode{
 	generate_bvh_node(boxen.into_iter().enumerate().collect())
 }