Fix bugs for pbrt bilinear patch

ray-tracing-tev/src/main.rs

@@ -230,7 +230,7 @@ fn main() {
             Pos3::new(3.0, 4.0, 1.5),
             Pos3::new(0.5, 0.5, 0.0),
             Dir3::new(0.0, 0.0, 1.0),
-            Float::to_radians(45.0),
+            Float::to_radians(90.0),
         );
 
         let s = &pbrt.scene;