all impl'd, should work

.rustfmt.toml

@@ -0,0 +1,4 @@
+imports_granularity = "Crate"
+group_imports = "StdExternalCrate"
+wrap_comments = true
+edition = "2024"

src/spindex.rs

@@ -1,10 +1,11 @@
-use crate::geom::Point;
+use std::cmp::Ordering;
+
 use bevy::{
     math::bounding::{Aabb2d, BoundingVolume, IntersectsVolume},
     prelude::*,
 };
-use ordered_float::OrderedFloat;
-use std::{cmp::Ordering, collections::BinaryHeap};
+
+use crate::geom::Point;
 
 // Epsilon value for zero-sizes bounding boxes/cubes.
 const EPSILON: f32 = 1e-10;
@@ -37,16 +38,15 @@ pub struct TreeNode {
 
 /// R*‑tree data structure for indexing 2D or 3D points.
 ///
-/// The tree is initialized with a maximum number of entries per node. If a node exceeds this
-/// number, it will split. The tree supports insertion, deletion, and range searches.
+/// The tree is initialized with a maximum number of entries per node. If a node
+/// exceeds this number, it will split. The tree supports insertion, deletion,
+/// and range searches.
 #[derive(Debug, Clone)]
 pub struct RStarTree {
     root: TreeNode,
     max_entries: usize,
-    min_entries: usize,
 }
 
-// Common trait implementations for R*-tree to reuse shared algorithms.
 impl Entry {
     fn as_leaf_obj(&self) -> Option<&Point> {
         match self {
@@ -94,18 +94,18 @@ impl TreeNode {
         let mut result = Vec::new();
         if self.is_leaf() {
             for entry in self.entries() {
-                if let Some(obj) = entry.as_leaf_obj() {
-                    if entry.mbr().intersects(bbox) {
-                        result.push(obj);
-                    }
+                if let Some(obj) = entry.as_leaf_obj()
+                    && entry.mbr().intersects(bbox)
+                {
+                    result.push(obj);
                 }
             }
         } else {
             for entry in self.entries() {
-                if let Some(child) = entry.child() {
-                    if entry.mbr().intersects(bbox) {
-                        result.extend_from_slice(&child.range_search_bbox(bbox));
-                    }
+                if let Some(child) = entry.child()
+                    && entry.mbr().intersects(bbox)
+                {
+                    result.extend_from_slice(&child.range_search_bbox(bbox));
                 }
             }
         }
@@ -119,14 +119,13 @@ impl TreeNode {
 
 impl RStarTree {
     pub fn new(max_entries: usize) -> Self {
-        let max_entries = max_entries.max(2);
+        let max_entries = max_entries.max(4);
         RStarTree {
             root: TreeNode {
                 entries: Vec::new(),
                 is_leaf: true,
             },
             max_entries,
-            min_entries: (max_entries as f32 * 0.4).ceil() as usize,
         }
     }
 
@@ -159,11 +158,11 @@ impl RStarTree {
                 if reinsert_level == Some(overflow_level) {
                     let old_entries = overflowed_node;
                     let (group1, group2) = split_entries(old_entries, self.max_entries);
-                    let mut mbr1 = group1[0].mbr().clone();
+                    let mut mbr1 = *group1[0].mbr();
                     for entry in group1.iter() {
                         mbr1 = mbr1.merge(entry.mbr());
                     }
-                    let mut mbr2 = group2[0].mbr().clone();
+                    let mut mbr2 = *group2[0].mbr();
                     for entry in group2.iter() {
                         mbr2 = mbr2.merge(entry.mbr());
                     }
@@ -212,7 +211,8 @@ impl RStarTree {
     ///
     /// # Returns
     ///
-    /// A vector of references to the objects whose minimum bounding volumes intersect the query.
+    /// A vector of references to the objects whose minimum bounding volumes
+    /// intersect the query.
     pub fn range_search_bbox(&self, query_bbox: &Aabb2d) -> Vec<&Point> {
         self.root.range_search_bbox(query_bbox)
     }
@@ -481,11 +481,11 @@ fn split_entries(mut entries: Vec<Entry>, max_entries: usize) -> (Vec<Entry>, Ve
         for k in min_entries..=entries.len() - min_entries {
             let group1 = &entries[..k];
             let group2 = &entries[k..];
-            let mut mbr1 = group1[0].mbr().clone();
+            let mut mbr1 = *group1[0].mbr();
             for entry in group1 {
                 mbr1 = mbr1.merge(entry.mbr());
             }
-            let mbr2 = group2[0].mbr().clone();
+            let mbr2 = *group2[0].mbr();
 
             let margin = mbr1.margin() + mbr2.margin();
             if margin < min_margin {
@@ -532,7 +532,8 @@ fn split_entries(mut entries: Vec<Entry>, max_entries: usize) -> (Vec<Entry>, Ve
 impl RStarTree {
     /// Performs a range search on the R*‑tree using a query object and radius.
     ///
-    /// The query object is wrapped into a bounding volume using `from_point_radius`.
+    /// The query object is wrapped into a bounding volume using
+    /// `from_point_radius`.
     ///
     /// # Arguments
     ///
@@ -555,7 +556,7 @@ impl RStarTree {
 
 fn entries_mbr(entries: &[Entry]) -> Option<Aabb2d> {
     let mut iter = entries.iter();
-    let first = iter.next()?.mbr().clone();
+    let first = *iter.next()?.mbr();
     Some(iter.fold(first, |acc, entry| acc.merge(entry.mbr())))
 }
 
@@ -572,6 +573,24 @@ impl Bvr for Aabb2d {
     }
 
     fn overlap(&self, other: &Aabb2d) -> f32 {
-        todo!()
+        let Vec2 {
+            x: self_width,
+            y: self_height,
+        } = 2.0 * self.half_size();
+
+        let self_center = self.center();
+        let other_center = other.center();
+
+        let Vec2 {
+            x: other_width,
+            y: other_height,
+        } = 2.0 * other.half_size();
+
+        let o_x = (self_center.x + self_width).min(other_center.x + other_width)
+            - self_center.x.max(other_center.x);
+        let o_y = (self_center.y + self_height).min(other_center.y + other_height)
+            - self_center.y.max(other_center.y);
+
+        (o_x * o_y).max(0.0)
     }
 }