Slight perf improvement

src/barnes_hut.rs

@@ -46,10 +46,11 @@ impl Octree {
 								particle: &mut RigidPoint,
 								cur_node: usize,
 								delta: f64) {
-		if self.nodes[cur_node].num_particles == 0 { return; }
+		let c_node = &self.nodes[cur_node];
+		if c_node.num_particles == 0 { return; }
 
-		let min_coord = self.nodes[cur_node].min_coord;
-		let max_coord = self.nodes[cur_node].max_coord;
+		let min_coord = c_node.min_coord;
+		let max_coord = c_node.max_coord;
 
 		let width = max_coord.x - min_coord.x;
 		let height = max_coord.y - min_coord.y;
@@ -63,8 +64,8 @@ impl Octree {
 		let theta_squared = THETA * THETA;
 		let ratio = s_squared / d_squared;
 		
-		if self.nodes[cur_node].num_particles == 1 || ratio < theta_squared {
-			println!("s/d = {}", ratio.sqrt());
+		if c_node.num_particles == 1 || ratio < theta_squared {
+			// println!("s/d = {}", ratio.sqrt());
 			//We can approximate
 			if d_squared < 0.1 { return; } // Worse, but higher-performance, method of smoothing
 			let other = &self.nodes[cur_node];
@@ -77,7 +78,7 @@ impl Octree {
 			//println!("A{}", self.nodes[cur_node].num_particles);
 			//Divide and conquer
 			for i in 0..8 {
-				self.barnes_hut_specific_node(particle, self.nodes[cur_node].children[i] as usize, delta);
+				self.barnes_hut_specific_node(particle, c_node.children[i] as usize, delta);
 			}
 		}
 	}