diff --git a/rtiow/renderer/src/bvh_triangles.rs b/rtiow/renderer/src/bvh_triangles.rs
index 6ba1434..c8d1fa2 100644
--- a/rtiow/renderer/src/bvh_triangles.rs
+++ b/rtiow/renderer/src/bvh_triangles.rs
@@ -320,19 +320,31 @@ mod tests {
             //Metal::new(Vec3::new(0.8, 0.8, 0.8), 0.2),
             //Lambertian::new(ConstantTexture::new(Vec3::new(1.0, 0.2, 0.2))),
         );
-        let rays = [
-            Ray::new([-1., 1., 1.], [1., 0., 0.], 0.),
-            Ray::new([21., 1., 1.], [-1., 0., 0.], 0.),
-            Ray::new([1., -1., 1.], [0., 1., 0.], 0.),
-            Ray::new([1., 21., 1.], [0., -1., 0.], 0.),
-            Ray::new([1., 1., -1.], [0., 0., 1.], 0.),
-            Ray::new([1., 1., 21.], [0., 0., -1.], 0.),
-            // TODO more
-        ];
+        let rays: Vec<_> = (1..20)
+            .flat_map(|y| {
+                (1..20).flat_map(move |x| {
+                    let x = x as f32;
+                    let y = y as f32;
+                    vec![
+                        Ray::new([-1., x, y], [1., 0., 0.], 0.),
+                        Ray::new([21., x, y], [-1., 0., 0.], 0.),
+                        Ray::new([x, -1., y], [0., 1., 0.], 0.),
+                        Ray::new([x, 21., y], [0., -1., 0.], 0.),
+                        Ray::new([x, y, -1.], [0., 0., 1.], 0.),
+                        Ray::new([x, y, 21.], [0., 0., -1.], 0.),
+                    ]
+                    .into_iter()
+                })
+            })
+            .collect();
 
         for (i, r) in rays.into_iter().enumerate() {
-            let c_hit = c.hit(r, 0., f32::MAX).expect("c_hit missed");
-            let s_hit = s.hit(r, 0., f32::MAX).expect("s_hit missed");
+            let c_hit = c
+                .hit(r, 0., f32::MAX)
+                .expect(&format!("c_hit missed {i}: {r:?}"));
+            let s_hit = s
+                .hit(r, 0., f32::MAX)
+                .expect(&format!("s_hit missed {i}: {r:?}"));
             assert_eq!(
                 c_hit.t, s_hit.t,
                 "{i}: [t] c_hit: {c_hit:?}, s_hit: {s_hit:?}"