diff --git a/kdtree/src/lib.rs b/kdtree/src/lib.rs
index e057b191..4b0c89bd 100644
--- a/kdtree/src/lib.rs
+++ b/kdtree/src/lib.rs
@@ -57,6 +57,7 @@ impl KdNode {
         Box::new(Self::Node { plane, left, right })
     }
 
+    #[inline]
     pub fn is_empty(&self) -> bool {
         match self {
             Self::Leaf(indices) => indices.is_empty(),
@@ -165,12 +166,14 @@ pub struct KdTree {
 }
 
 impl KdTree {
+    #[inline]
     pub fn iter_nodes(&self) -> KdTreeNodeIter<'_> {
         KdTreeNodeIter {
             stack: vec![(1, &self.root)],
         }
     }
 
+    #[inline]
     pub fn iter_leafs(&self) -> impl Iterator<Item = (usize, &Vec<u32>)> {
         self.iter_nodes().filter_map(|(depth, node)| match node {
             KdNode::Leaf(indices) => Some((depth, indices)),
@@ -178,6 +181,7 @@ impl KdTree {
         })
     }
 
+    #[inline]
     pub fn intersect(
         &self,
         ray: &Ray,
diff --git a/kdtree/src/split.rs b/kdtree/src/split.rs
index 869e3c81..1ac43311 100644
--- a/kdtree/src/split.rs
+++ b/kdtree/src/split.rs
@@ -15,7 +15,7 @@ pub(crate) fn clip_geometries(geometries: &[Geometry], cell: &KdCell) -> Vec<(u3
         .collect::<Vec<_>>()
 }
 
-pub fn partition_triangles(
+pub(crate) fn partition_triangles(
     clipped_triangles: &[(u32, Aabb)],
     plane: &Aap,
 ) -> (Vec<u32>, Vec<u32>, Vec<u32>) {
@@ -42,7 +42,7 @@ pub fn partition_triangles(
     (left_triangles, middle_triangles, right_triangles)
 }
 
-pub struct SplitPartitioning {
+pub(crate) struct SplitPartitioning {
     pub left_aabb: Aabb,
     pub right_aabb: Aabb,
     pub left_indices: Vec<u32>,
@@ -50,7 +50,11 @@ pub struct SplitPartitioning {
     pub right_indices: Vec<u32>,
 }
 
-pub fn split_and_partition(clipped: &[(u32, Aabb)], aabb: &Aabb, plane: Aap) -> SplitPartitioning {
+pub(crate) fn split_and_partition(
+    clipped: &[(u32, Aabb)],
+    aabb: &Aabb,
+    plane: Aap,
+) -> SplitPartitioning {
     let (left_aabb, right_aabb) = aabb.split(&plane);
     let (left_indices, middle_indices, right_indices) = partition_triangles(clipped, &plane);
     SplitPartitioning {