From 2156e0ce68e2da9099fbc212665f69aafdf0e91c Mon Sep 17 00:00:00 2001
From: maddiebaka <madeline@cray.lgbt>
Date: Wed, 14 Jun 2023 11:07:11 -0400
Subject: [PATCH] Fix sphere intersection calculation error

---
 src/main.rs | 57 +++++++++++++++++++++++++++--------------------------
 1 file changed, 29 insertions(+), 28 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 4588479..e6d26eb 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,4 +1,4 @@
-use std::mem;
+use std::f32;
 use std::ops::{Add,Mul};
 
 #[macro_use]
@@ -217,10 +217,10 @@ impl Intersectable for Sphere {
 
     if t0 < 0.0 && t1 < 0.0 {
       None
-    //} else if t0 < 0.0 {
-    //  Some(t1)
-    //} else if t1 < 0.0 {
-    //  Some(t0)
+    } else if t0 < 0.0 {
+      Some(t1)
+    } else if t1 < 0.0 {
+      Some(t0)
     } else {
       let distance = if t0 < t1 { t0 } else { t1 };
       Some(distance)
@@ -281,7 +281,7 @@ impl Intersectable for Element {
 
 fn create_reflection(normal: Vec3<f64>, incident: Vec3<f64>, hit_point: Vec3<f64>, bias: f64) -> Ray {
     Ray {
-        pos: hit_point + (normal.normalize() * bias),
+        pos: hit_point + (normal.normalize()),
         dir: incident - (2.0 * incident.dot(&normal) * normal),
     }
 }
@@ -327,8 +327,9 @@ fn shade_diffuse(camera: &OrthoCamera, object: &Element, hit_point: Vec3<f64>, s
     let light_intensity = if in_light { camera.light.intensity } else { 0.0 };
 
     let light_power = (surface_normal.normalize().dot(&direction_to_light.normalize()) as f32).max(0.0);
+    let light_reflected = material.albedo / f32::consts::PI;
 
-    let light_color = light_intensity * light_power;
+    let light_color = light_intensity * light_power * light_reflected;
     color = color + (material.coloration * light_color);
 
     return color;
@@ -356,24 +357,24 @@ fn main() {
 //  camera.spheres.push(Sphere::new(Vec3::new(125.0, 75.0, 100.0), 20.0));
 //  camera.spheres.push(Sphere::new(Vec3::new(115.0, 175.0, 100.0), 60.0));
 //  camera.spheres.push(Sphere::new(Vec3::new(0.0, 0.0, 100.0), 10.0));
-  //for i in 0..2 {
-  //  let mut rng = rand::thread_rng();
-  //  let x: f64 = rng.gen::<f64>() * 250.0 * 10.0;
-  //  let y: f64 = rng.gen::<f64>() * 250.0 * 10.0;
-  //  let z: f64 = rng.gen::<f64>() * 250.0 * 10.0;
-  //  let radius: f64 = rng.gen::<f64>() * 40.0 * 10.0;
-  //  let red: f32 = rng.gen::<f32>() * 100.0;
-  //  let green: f32 = rng.gen::<f32>() * 100.0;
-  //  let blue: f32 = rng.gen::<f32>() * 100.0;
-  //  let sphere = Sphere {
-  //    pos: Vec3::new(x, y, 100.0),
-  //    radius: radius,
-  //    //material: Material::new(Color::new(red, green, blue), 2.0, SurfaceType::Reflective { reflectivity: 0.2 })
-  //    material: Material::new(Color::new(red, green, blue), 2.0, SurfaceType::Diffuse),
-  //  };
-  //  camera.elements.push(Element::Sphere(sphere));
-  //  //camera.spheres.push(Sphere::new(Vec3::new(x, y, 100.0), radius));
-  //}
+  for i in 0..15 {
+    let mut rng = rand::thread_rng();
+    let x: f64 = rng.gen::<f64>() * 250.0 * 10.0;
+    let y: f64 = rng.gen::<f64>() * 250.0 * 10.0;
+    let z: f64 = rng.gen::<f64>() * 250.0 * 10.0;
+    let radius: f64 = rng.gen::<f64>() * 40.0 * 10.0;
+    let red: f32 = rng.gen::<f32>() * 100.0;
+    let green: f32 = rng.gen::<f32>() * 100.0;
+    let blue: f32 = rng.gen::<f32>() * 100.0;
+    let sphere = Sphere {
+      pos: Vec3::new(x, y, 100.0),
+      radius: radius,
+      material: Material::new(Color::new(red, green, blue), 2.0, SurfaceType::Reflective { reflectivity: rng.gen::<f32>() }),
+      //material: Material::new(Color::new(red, green, blue), 2.0, SurfaceType::Diffuse),
+    };
+    camera.elements.push(Element::Sphere(sphere));
+    //camera.spheres.push(Sphere::new(Vec3::new(x, y, 100.0), radius));
+  }
 
   let back_plane = Plane {
     //pos: Vec3::new(0.0, 0.0, 100.0),
@@ -396,15 +397,15 @@ fn main() {
     pos: Vec3::new(1280.0, 1290.0, 1000.0),
     radius: 300.0,
     //material: Material::new(Color::new(20.0, 20.0, 20.0), 2.0, SurfaceType::Diffuse),
-    material: Material::new(Color::new(255.0, 255.0, 255.0), 2.0, SurfaceType::Reflective { reflectivity: 0.9 }),
+    material: Material::new(Color::new(255.0, 255.0, 255.0), 2.0, SurfaceType::Reflective { reflectivity: 0.8 }),
   };
   camera.elements.push(Element::Sphere(center_sphere));
 
   let left_sphere = Sphere {
     pos: Vec3::new(200.0, 1800.0, 500.0),
     radius: 200.0,
-    //material: Material::new(Color::new(255.0, 20.0, 20.0), 2.0, SurfaceType::Reflective { reflectivity: 0.1 })
-    material: Material::new(Color::new(20.0, 20.0, 200.0), 2.0, SurfaceType::Diffuse),
+    material: Material::new(Color::new(255.0, 20.0, 20.0), 2.0, SurfaceType::Reflective { reflectivity: 0.1 }),
+    //material: Material::new(Color::new(20.0, 20.0, 200.0), 2.0, SurfaceType::Diffuse),
   };
   camera.elements.push(Element::Sphere(left_sphere));