From 7b826e11be342fa363f48a2afe82d8d33ee9bbad Mon Sep 17 00:00:00 2001
From: Quaternions <krakow20@gmail.com>
Date: Thu, 25 Jul 2024 15:37:55 -0700
Subject: [PATCH] special method converts Bvh into Bvh with weights

---
 src/bvh.rs | 66 +++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 55 insertions(+), 11 deletions(-)

diff --git a/src/bvh.rs b/src/bvh.rs
index e5427f9..ab73f65 100644
--- a/src/bvh.rs
+++ b/src/bvh.rs
@@ -10,26 +10,31 @@ use crate::aabb::Aabb;
 //sort the centerpoints on each axis (3 lists)
 //bv is put into octant based on whether it is upper or lower in each list
 
-enum BvhNodeContent<T>{
-	Branch(Vec<BvhNode<T>>),
+pub enum RecursiveContent<R,T>{
+	Branch(Vec<R>),
 	Leaf(T),
 }
-impl<T> Default for BvhNodeContent<T>{
+impl<R,T> Default for RecursiveContent<R,T>{
 	fn default()->Self{
 		Self::Branch(Vec::new())
 	}
 }
 #[derive(Default)]
 pub struct BvhNode<T>{
-	content:BvhNodeContent<T>,
+	content:RecursiveContent<BvhNode<T>,T>,
+	aabb:Aabb,
+}
+pub struct BvhWeightNode<W,T>{
+	content:RecursiveContent<BvhWeightNode<W,T>,T>,
+	weight:W,
 	aabb:Aabb,
 }
 
 impl<T> BvhNode<T>{
 	pub fn the_tester<F:FnMut(&T)>(&self,aabb:&Aabb,f:&mut F){
 		match &self.content{
-			BvhNodeContent::Leaf(model)=>f(model),
-			BvhNodeContent::Branch(children)=>for child in children{
+			RecursiveContent::Leaf(model)=>f(model),
+			RecursiveContent::Branch(children)=>for child in children{
 				//this test could be moved outside the match statement
 				//but that would test the root node aabb
 				//you're probably not going to spend a lot of time outside the map,
@@ -42,8 +47,47 @@ impl<T> BvhNode<T>{
 	}
 	pub fn into_visitor<F:FnMut(T)>(self,f:&mut F){
 		match self.content{
-			BvhNodeContent::Leaf(model)=>f(model),
-			BvhNodeContent::Branch(children)=>for child in children{
+			RecursiveContent::Leaf(model)=>f(model),
+			RecursiveContent::Branch(children)=>for child in children{
+				child.into_visitor(f)
+			},
+		}
+	}
+	pub fn weigh_contents<W:Copy+std::iter::Sum<W>,F:Fn(&T)->W>(self,f:&F)->BvhWeightNode<W,T>{
+		match self.content{
+			RecursiveContent::Leaf(model)=>BvhWeightNode{
+				weight:f(&model),
+				content:RecursiveContent::Leaf(model),
+				aabb:self.aabb,
+			},
+			RecursiveContent::Branch(children)=>{
+				let branch:Vec<BvhWeightNode<W,T>>=children.into_iter().map(|child|
+					child.weigh_contents(f)
+				).collect();
+				BvhWeightNode{
+					weight:branch.iter().map(|node|node.weight).sum(),
+					content:RecursiveContent::Branch(branch),
+					aabb:self.aabb,
+				}
+			},
+		}
+	}
+}
+
+impl <W,T> BvhWeightNode<W,T>{
+	pub const fn weight(&self)->&W{
+		&self.weight
+	}
+	pub const fn aabb(&self)->&Aabb{
+		&self.aabb
+	}
+	pub fn into_content(self)->RecursiveContent<BvhWeightNode<W,T>,T>{
+		self.content
+	}
+	pub fn into_visitor<F:FnMut(T)>(self,f:&mut F){
+		match self.content{
+			RecursiveContent::Leaf(model)=>f(model),
+			RecursiveContent::Branch(children)=>for child in children{
 				child.into_visitor(f)
 			},
 		}
@@ -61,12 +105,12 @@ fn generate_bvh_node<T>(boxen:Vec<(T,Aabb)>,force:bool)->BvhNode<T>{
 		let nodes=boxen.into_iter().map(|b|{
 			aabb.join(&b.1);
 			BvhNode{
-				content:BvhNodeContent::Leaf(b.0),
+				content:RecursiveContent::Leaf(b.0),
 				aabb:b.1,
 			}
 		}).collect();
 		BvhNode{
-			content:BvhNodeContent::Branch(nodes),
+			content:RecursiveContent::Branch(nodes),
 			aabb,
 		}
 	}else{
@@ -123,7 +167,7 @@ fn generate_bvh_node<T>(boxen:Vec<(T,Aabb)>,force:bool)->BvhNode<T>{
 			generate_bvh_node(list_list.remove(0),true)
 		}else{
 			BvhNode{
-				content:BvhNodeContent::Branch(
+				content:RecursiveContent::Branch(
 					list_list.into_iter().map(|b|{
 						let node=generate_bvh_node(b,false);
 						aabb.join(&node.aabb);