diff --git a/src/trace.rs b/src/trace.rs
index baa2633..984f9d9 100644
--- a/src/trace.rs
+++ b/src/trace.rs
@@ -120,10 +120,12 @@ pub struct Hit {
 
 impl Scene {
 	pub fn trace_ray(&self, ray: Ray) -> Option<Hit> {
+		const EPS: f32 = -1e-3;
 		let hit = self
 			.objects
 			.iter()
 			.filter_map(|obj| obj.trace_ray(ray))
+			.filter(|h| h.dist >= EPS)
 			.min_by(|a, b| f32::total_cmp(&a.dist, &b.dist))?;
 		Some(Hit {
 			incident: Ray {