From 6da6944fa3b724decc97c8b0f2005e40830facfb Mon Sep 17 00:00:00 2001
From: numzero <numzer0@yandex.ru>
Date: Sun, 17 Nov 2024 01:02:31 +0300
Subject: [PATCH] Fix a precision issue

---
 src/shape/cylinder.rs | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/shape/cylinder.rs b/src/shape/cylinder.rs
index 0f06a21..1c384b6 100644
--- a/src/shape/cylinder.rs
+++ b/src/shape/cylinder.rs
@@ -93,7 +93,7 @@ impl YCylinder {
 		// 2. (ray.pos.x + t * ray.dir.x)² + (ray.pos.z + t * ray.dir.z)² = radius²
 		let pos = ray.pos.xz();
 		let dir = ray.dir.xz();
-		if dir.length_squared() < 1e-3 {
+		if dir.length_squared() < 1e-6 * ray.dir.length_squared() {
 			if pos.length_squared() >= self.radius.powi(2) {
 				return None;
 			}
@@ -215,6 +215,14 @@ mod tests {
 			r.trace_into(ray(vec3(1.4142135, -3., 1.4142135), vec3(-1., 1., -1.))),
 			Some(0.)
 		);
+		assert_eq!(
+			YCylinder {
+				half_length: 300.,
+				radius: 50.
+			}
+			.trace_into(ray(vec3(-125., 375., 0.), vec3(3., -11., 0.) / 1024.)),
+			Some(25600.)
+		);
 
 		assert_abs_diff_eq!(
 			r.trace_out_of(ray(vec3(0., 0., 0.), vec3(1., 1., 1.))).unwrap(),