Viel Stuff, hittable objects auslagern

.gitignore

@@ -1 +1,2 @@
 /target
+*.ppm

src/hittable.rs

@@ -0,0 +1,57 @@
+use super::Point3;
+use super::Ray;
+use super::Vec3;
+
+pub struct HitRecord {
+    p: Point3,
+    normal: Vec3,
+    t: f64,
+}
+
+pub struct Sphere {
+    center: Point3,
+    radius: f64,
+}
+
+pub trait Hittable {
+    fn hit(&self, r: Ray, t_min: f64, t_max: f64, rec: &mut HitRecord) -> bool;
+}
+
+impl Sphere {
+    fn new(cen: Point3, r: f64) -> Self {
+        Sphere {
+            center: cen,
+            radius: r,
+        }
+    }
+}
+
+impl Hittable for Sphere {
+    fn hit(&self, r: Ray, t_min: f64, t_max: f64, rec: &mut HitRecord) -> bool {
+        let oc = r.origin() - self.center;
+        let a = r.direction().length_squared(); // gleiches Ergebnis wie Skalarprodukt
+        let b = 2.0 * Vec3::dot(oc, r.direction());
+        let c = oc.length_squared() - self.radius * self.radius;
+
+        let discriminant = b * b - 4.0 * a * c;
+        if discriminant < 0.0 {
+            return false;
+        }
+
+        let sqrtd = discriminant.sqrt();
+
+        let root = (-b / 2.0 - sqrtd) / a;
+        if root < t_min || t_max < root {
+            let root2 = (-b / 2.0 + sqrtd) / a;
+            if root2 < t_min || t_max < root {
+                return false;
+            }
+        }
+
+        rec.t = root;
+        rec.p = r.at(rec.t);
+        rec.normal = (rec.p - self.center) / self.radius;
+
+        return true;
+    }
+}

src/main.rs

@@ -1,4 +1,5 @@
 mod color;
+mod hittable;
 mod ray;
 mod vec3;
 use ray::Ray;
@@ -12,9 +13,9 @@ use vec3::Vec3;
 
 fn hit_sphere(center: &Point3, radius: f64, r: &Ray) -> f64 {
     let oc = r.origin() - *center;
-    let a = Vec3::dot(r.direction(), r.direction());
+    let a = r.direction().length_squared(); // gleiches Ergebnis wie Skalarprodukt
     let b = 2.0 * Vec3::dot(oc, r.direction());
-    let c = Vec3::dot(oc, oc) - radius * radius;
+    let c = oc.length_squared() - radius * radius;
     let discriminant = b * b - 4.0 * a * c;
 
     if discriminant < 0.0 {
@@ -42,7 +43,7 @@ fn main() {
 
     // Image
     let aspect_ratio = 16.0 / 9.0;
-    let image_width = 400;
+    let image_width = 2000;
     let image_height = (image_width as f64 / aspect_ratio) as u64;
 
     // Camera