From a82441677df93b939e1ba87fb1ddf9fb5eaa9be3 Mon Sep 17 00:00:00 2001
From: numzero <numzer0@yandex.ru>
Date: Mon, 27 May 2024 19:16:59 +0300
Subject: [PATCH] Functional tracer

---
 src/bin/flat.rs | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/src/bin/flat.rs b/src/bin/flat.rs
index 5163a01..1d70cf3 100644
--- a/src/bin/flat.rs
+++ b/src/bin/flat.rs
@@ -116,13 +116,9 @@ impl Space {
 
 	fn trace_boundary(&self, ray: Ray) -> Ray {
 		assert_eq!(self.which_subspace(ray.pos), Boundary);
-		let mut ray = ray;
-		loop {
-			ray = self.trace_step(ray);
-			if self.which_subspace(ray.pos) != Boundary {
-				break ray;
-			}
-		}
+		std::iter::successors(Some(ray), |&ray| Some(self.trace_step(ray)))
+			.find(|&ray| self.which_subspace(ray.pos) != Boundary)
+			.expect("Can't get outta the wall!")
 	}
 }