Add Scene type and Sphere intersect

8 files changed, 128 insertions, 22 deletions

diff --git a/src/core/ray.rs b/src/core/ray.rs
index 7d73b93..54af639 100644
--- a/src/core/ray.rs
+++ b/src/core/ray.rs
@@ -1,6 +1,7 @@
 use crate::core::Vector3f;
 
 pub struct Ray {
-    origin: Vector3f,
-    direction: Vector3f,
+    pub origin: Vector3f,
+    pub direction: Vector3f,
 }
+
diff --git a/src/core/vector3.rs b/src/core/vector3.rs
index da09ceb..e3aa9a6 100644
--- a/src/core/vector3.rs
+++ b/src/core/vector3.rs
@@ -1,5 +1,5 @@
 use crate::{Float, Number};
-use std::ops::{Sub, Add};
+use std::ops::{Sub, Add, DivAssign};
 
 #[derive(Clone, Copy)]
 pub struct Vector3<T: Number> {
@@ -19,7 +19,7 @@ impl<T: Number> Vector3<T> {
         }
     }
 
-    pub fn new_xy(x: T, y: T, z: T) -> Vector3<T> {
+    pub fn new_xyz(x: T, y: T, z: T) -> Vector3<T> {
         Vector3 { x, y, z}
     }
 }
@@ -27,7 +27,7 @@ impl<T: Number> Vector3<T> {
 impl<T: Number> Sub for Vector3<T> {
     type Output = Self;
     fn sub(self, op: Self) -> Self::Output {
-        Self::new_xy(
+        Self::new_xyz(
             self.x - op.x,
             self.y - op.y,
             self.z - op.z,
@@ -38,10 +38,47 @@ impl<T: Number> Sub for Vector3<T> {
 impl<T: Number> Add for Vector3<T> {
     type Output = Self;
     fn add(self, op: Self) -> Self::Output {
-        Self::new_xy(
+        Self::new_xyz(
             self.x + op.x,
             self.y + op.y,
             self.z + op.z,
         )
     }
 }
+
+impl<T: Number> DivAssign<T> for Vector3<T> {
+    fn div_assign(&mut self, op: T) {
+        self.x /= op;
+        self.y /= op;
+        self.z /= op;
+    }
+}
+
+impl Vector3f {
+    pub fn len_squared(&self) -> Float {
+        self.x * self.x + self.y * self.y + self.z * self.z
+    }
+
+    pub fn len(&self) -> Float {
+        self.len_squared().sqrt()
+    }
+
+    pub fn dot(&self, op: &Self) -> Float {
+        self.x * op.x + self.y * op.y + self.z * op.z
+    }
+
+    pub fn norm_in(&mut self) {
+        let len = self.len();
+        if len == 0.0 {
+            *self = Self::new(0.0);
+        }
+
+        *self /= len;
+    }
+
+    pub fn norm(&self) -> Self {
+        let mut new = self.clone();
+        new.norm_in();
+        new
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index c78c51e..a120f0d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,8 +1,9 @@
 pub mod core;
 pub mod camera;
 mod scene;
+mod render;
 
-use std::ops::{Add, Sub, Mul};
+use std::ops::{Add, Sub, Mul, DivAssign};
 use std::cmp;
 
 pub trait Number:
@@ -10,7 +11,8 @@ pub trait Number:
     cmp::PartialOrd +
     Sub<Output = Self> +
     Add<Output = Self> +
-    Mul<Output = Self>
+    Mul<Output = Self> +
+    DivAssign
 {}
 
 impl Number for usize {}
diff --git a/src/main.rs b/src/main.rs
index c984176..524f613 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,12 +1,4 @@
-use pathtrace::camera::film::Film;
-use pathtrace::vector::{Vector2i};
-use pathtrace::bound::Bound2i;
 
 
 fn main() {
-
-    let film = Film::new(Vector2i::new(100));
-    let tile = film.get_tile(&Bound2i::new_xyxy(10, 10, 100, 100));
-
-    //println!("Yo {}", tile.bounds.min.x);
 }
diff --git a/src/scene/mod.rs b/src/scene/mod.rs
index 3482bb6..13c5e23 100644
--- a/src/scene/mod.rs
+++ b/src/scene/mod.rs
@@ -1,3 +1,4 @@
-mod shapes;
-
+pub mod shapes;
 
+mod scene;
+pub use scene::*;
diff --git a/src/scene/scene.rs b/src/scene/scene.rs
new file mode 100644
index 0000000..a2f5b88
--- /dev/null
+++ b/src/scene/scene.rs
@@ -0,0 +1,38 @@
+use super::shapes::Shape;
+use crate::Float;
+use crate::core::Ray;
+
+pub struct Scene {
+    shps: Vec<Box<dyn Shape>>,
+}
+
+pub struct Intersection<'a> {
+    pub shp: &'a dyn Shape,
+    pub t: Float,
+}
+
+impl Scene {
+    pub fn new() -> Self {
+        Self {
+            shps: Vec::new(),
+        }
+    }
+
+    pub fn add_shape(&mut self, shp: Box<dyn Shape>) {
+        self.shps.push(shp);
+    }
+
+    pub fn intersect(&self, ray: Ray) -> Option<Intersection> {
+        for shp in self.shps.iter() {
+            if let Some(t) = shp.intersect(&ray) {
+                return Some(Intersection {
+                    shp: shp.as_ref(),
+                    t,
+                })
+            }
+        }
+
+        None
+    }
+}
+
diff --git a/src/scene/shapes/mod.rs b/src/scene/shapes/mod.rs
index 76fb6f2..7fbb8db 100644
--- a/src/scene/shapes/mod.rs
+++ b/src/scene/shapes/mod.rs
@@ -5,8 +5,6 @@ pub use sphere::Sphere;
 use crate::core::Ray;
 use crate::Float;
 
-trait Shape {
-    // 
-    fn intersect(ray: Ray) -> Float;
-    fn intersect_
+pub trait Shape {
+    fn intersect(&self, ray: &Ray) -> Option<Float>;
 }
diff --git a/src/scene/shapes/sphere.rs b/src/scene/shapes/sphere.rs
index 9598422..f8ae11e 100644
--- a/src/scene/shapes/sphere.rs
+++ b/src/scene/shapes/sphere.rs
@@ -1,5 +1,6 @@
 use crate::Float;
 use crate::core::{Ray, Vector3f};
+use super::Shape;
 
 pub struct Sphere {
     radius: Float,
@@ -14,3 +15,39 @@ impl Sphere {
         }
     }
 }
+
+impl Shape for Sphere {
+    // Implementation from ray tracing in a weekend
+    fn intersect(&self, ray: &Ray) -> Option<Float> {
+        let oc = ray.origin - self.center;
+        let a = ray.direction.len_squared();
+        let half_b = oc.dot(&ray.direction);
+        let c = oc.len_squared() - self.radius * self.radius;
+        let disc = half_b*half_b - a*c;
+
+        if disc < 0.0 {
+            None
+        } else {
+            Some( (-half_b - disc.sqrt()) / a)
+        }
+
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn sphere_intersect() {
+        let sph = Sphere::new(2.0, Vector3f::new_xyz(2.0, 3.0, 4.0));
+
+        let ray = Ray {
+            origin: Vector3f::new_xyz(1.0, 0.0, 0.0),
+            direction: Vector3f::new_xyz(0.0, 1.0, 1.5).norm(),
+        };
+
+        let dist = sph.intersect(&ray);
+        assert!((dist.unwrap() - 3.28).abs() < 0.01);
+    }
+}