1 files changed, 15 insertions, 50 deletions

diff --git a/src/sphere.rs b/src/sphere.rs
index 59ca498..573f891 100644
--- a/src/sphere.rs
+++ b/src/sphere.rs
@@ -6,7 +6,10 @@ use cgmath::{dot, Vector3};
 use core::borrow::Borrow;
 
 pub struct Sphere {
-    center: Vector3<f64>,
+    center0: Vector3<f64>,
+    center1: Vector3<f64>,
+    time0: f64,
+    time1: f64,
     radius: f64,
     material: Box<dyn Material + std::marker::Sync>,
 }
@@ -14,68 +17,30 @@ pub struct Sphere {
 impl Sphere {
     pub fn new(
         center: Vector3<f64>,
+        time0: f64,
+        time1: f64,
         radius: f64,
         material: Box<dyn Material + std::marker::Sync>,
     ) -> Sphere {
         Sphere {
-            center,
+            center0: center,
+            center1: center,
+            time0,
+            time1,
             radius,
             material,
         }
     }
-}
-
-impl Hittable for Sphere {
-    fn is_hit(&self, ray: &Ray, t_min: f64, t_max: f64) -> Option<Hit> {
-        let oc = ray.orig - self.center;
-        let a = ray.dir.magnitude2();
-        let b = dot(oc, ray.dir);
-        let c = oc.magnitude2() - self.radius * self.radius;
-        let discriminant = b * b - a * c;
-
-        if discriminant > 0.0 {
-            let soln = (-b - discriminant.sqrt()) / a;
-            if soln < t_max && soln > t_min {
-                return Some(Hit::new(
-                    ray,
-                    soln,
-                    (ray.at(soln) - self.center) / self.radius,
-                    self.material.borrow(),
-                ));
-            }
-            let soln = (-b + discriminant.sqrt()) / a;
-            if soln < t_max && soln > t_min {
-                return Some(Hit::new(
-                    ray,
-                    soln,
-                    (ray.at(soln) - self.center) / self.radius,
-                    self.material.borrow(),
-                ));
-            }
-        }
-        None
-    }
-}
 
-struct MovingSphere {
-    center0: Vector3<f64>,
-    center1: Vector3<f64>,
-    time0: f64,
-    time1: f64,
-    radius: f64,
-    material: Box<dyn Material + std::marker::Sync>,
-}
-
-impl MovingSphere {
-    pub fn new(
+    pub fn new_moving(
         center0: Vector3<f64>,
         center1: Vector3<f64>,
         time0: f64,
         time1: f64,
         radius: f64,
         material: Box<dyn Material + std::marker::Sync>,
-    ) -> MovingSphere {
-        MovingSphere {
+    ) -> Sphere {
+        Sphere {
             center0,
             center1,
             time0,
@@ -87,11 +52,11 @@ impl MovingSphere {
 
     pub fn center(&self, time: f64) -> Vector3<f64> {
         self.center0
-            + ((time + self.time0) / (self.time0 + self.time1)) * (self.center1 - self.center0)
+            + ((time - self.time0) / (self.time1 - self.time0)) * (self.center1 - self.center0)
     }
 }
 
-impl Hittable for MovingSphere {
+impl Hittable for Sphere {
     fn is_hit(&self, ray: &Ray, t_min: f64, t_max: f64) -> Option<Hit> {
         let oc = ray.orig - self.center(ray.time);
         let a = ray.dir.magnitude2();