Merge branch 'dev-minor' into subchapters

Author: hollasch

CHANGELOG.md

@@ -5,14 +5,17 @@ Change Log -- Ray Tracing in One Weekend
 # v3.1.0 (in progress)
 
 ### Common
+- Change: Minor change to use new `point3` and `color` type aliases for `vec3` (#422)
 - New: subchapters throughout all three books (#267)
+- Fix: Scattered improvements to the text.
 
 ### _In One Weekend_
 - Fix: Update image and size for first PPM image
 - Fix: Update image and size for blue-to-white gradient image
 - Fix: Update image and size for simple red sphere render
 - Fix: Update image and size for sphere with normal-vector coloring
 - Fix: Improve image size and aspect ratio calculation to make size changes easier
+- Fix: Added `t` parameter back into `hit_record` at correct place
 
 
 ----------------------------------------------------------------------------------------------------

books/RayTracingInOneWeekend.html

@@ -17,7 +17,7 @@
 class material;
 
 struct hit_record {
-    vec3 p;
+    point3 p;
     vec3 normal;
     shared_ptr<material> mat_ptr;
     double t;
@@ -29,6 +29,7 @@ struct hit_record {
     }
 };
 
+
 class hittable {
     public:
         virtual bool hit(const ray& r, double t_min, double t_max, hit_record& rec) const = 0;

books/RayTracingTheNextWeek.html

@@ -19,48 +19,49 @@
 #include <iostream>
 
 
-vec3 ray_color(const ray& r, const hittable& world, int depth) {
+color ray_color(const ray& r, const hittable& world, int depth) {
     hit_record rec;
 
     // If we've exceeded the ray bounce limit, no more light is gathered.
     if (depth <= 0)
-        return vec3(0,0,0);
+        return color(0,0,0);
 
     if (world.hit(r, 0.001, infinity, rec)) {
         ray scattered;
-        vec3 attenuation;
+        color attenuation;
         if (rec.mat_ptr->scatter(r, rec, attenuation, scattered))
             return attenuation * ray_color(scattered, world, depth-1);
-        return vec3(0,0,0);
+        return color(0,0,0);
     }
 
     vec3 unit_direction = unit_vector(r.direction());
     auto t = 0.5*(unit_direction.y() + 1.0);
-    return (1.0-t)*vec3(1.0, 1.0, 1.0) + t*vec3(0.5, 0.7, 1.0);
+    return (1.0-t)*color(1.0, 1.0, 1.0) + t*color(0.5, 0.7, 1.0);
 }
 
 
 hittable_list random_scene() {
     hittable_list world;
 
     world.add(
-        make_shared<sphere>(vec3(0,-1000,0), 1000, make_shared<lambertian>(vec3(0.5, 0.5, 0.5)))
+        make_shared<sphere>(
+            point3(0,-1000,0), 1000, make_shared<lambertian>(color(0.5, 0.5, 0.5)))
     );
 
     int i = 1;
     for (int a = -11; a < 11; a++) {
         for (int b = -11; b < 11; b++) {
             auto choose_mat = random_double();
-            vec3 center(a + 0.9*random_double(), 0.2, b + 0.9*random_double());
+            point3 center(a + 0.9*random_double(), 0.2, b + 0.9*random_double());
             if ((center - vec3(4, 0.2, 0)).length() > 0.9) {
                 if (choose_mat < 0.8) {
                     // diffuse
-                    auto albedo = vec3::random() * vec3::random();
+                    auto albedo = color::random() * color::random();
                     world.add(
                         make_shared<sphere>(center, 0.2, make_shared<lambertian>(albedo)));
                 } else if (choose_mat < 0.95) {
                     // metal
-                    auto albedo = vec3::random(.5, 1);
+                    auto albedo = color::random(.5, 1);
                     auto fuzz = random_double(0, .5);
                     world.add(
                         make_shared<sphere>(center, 0.2, make_shared<metal>(albedo, fuzz)));
@@ -73,11 +74,16 @@ hittable_list random_scene() {
     }
 
     world.add(
-        make_shared<sphere>(vec3(0, 1, 0), 1.0, make_shared<dielectric>(1.5)));
+        make_shared<sphere>(
+            point3(0, 1, 0), 1.0, make_shared<dielectric>(1.5)));
+
     world.add(
-        make_shared<sphere>(vec3(-4, 1, 0), 1.0, make_shared<lambertian>(vec3(0.4, 0.2, 0.1))));
+        make_shared<sphere>(
+            point3(-4, 1, 0), 1.0, make_shared<lambertian>(color(0.4, 0.2, 0.1))));
+
     world.add(
-        make_shared<sphere>(vec3(4, 1, 0), 1.0, make_shared<metal>(vec3(0.7, 0.6, 0.5), 0.0)));
+        make_shared<sphere>(
+            point3(4, 1, 0), 1.0, make_shared<metal>(color(0.7, 0.6, 0.5), 0.0)));
 
     return world;
 }
@@ -94,8 +100,8 @@ int main() {
 
     auto world = random_scene();
 
-    vec3 lookfrom(13,2,3);
-    vec3 lookat(0,0,0);
+    point3 lookfrom(13,2,3);
+    point3 lookat(0,0,0);
     vec3 vup(0,1,0);
     auto dist_to_focus = 10.0;
     auto aperture = 0.1;
@@ -105,14 +111,14 @@ int main() {
     for (int j = image_height-1; j >= 0; --j) {
         std::cerr << "\rScanlines remaining: " << j << ' ' << std::flush;
         for (int i = 0; i < image_width; ++i) {
-            vec3 color;
+            color pixel_color;
             for (int s = 0; s < samples_per_pixel; ++s) {
                 auto u = (i + random_double()) / image_width;
                 auto v = (j + random_double()) / image_height;
                 ray r = cam.get_ray(u, v);
-                color += ray_color(r, world, max_depth);
+                pixel_color += ray_color(r, world, max_depth);
             }
-            color.write_color(std::cout, samples_per_pixel);
+            pixel_color.write_color(std::cout, samples_per_pixel);
         }
     }
 

books/RayTracingTheRestOfYourLife.html

@@ -27,7 +27,7 @@ double schlick(double cosine, double ref_idx) {
 class material  {
     public:
         virtual bool scatter(
-            const ray& r_in, const hit_record& rec, vec3& attenuation, ray& scattered
+            const ray& r_in, const hit_record& rec, color& attenuation, ray& scattered
         ) const = 0;
 };
 
@@ -37,9 +37,9 @@ class dielectric : public material {
         dielectric(double ri) : ref_idx(ri) {}
 
         virtual bool scatter(
-            const ray& r_in, const hit_record& rec, vec3& attenuation, ray& scattered
+            const ray& r_in, const hit_record& rec, color& attenuation, ray& scattered
         ) const {
-            attenuation = vec3(1.0, 1.0, 1.0);
+            attenuation = color(1.0, 1.0, 1.0);
             double etai_over_etat = (rec.front_face) ? (1.0 / ref_idx) : (ref_idx);
 
             vec3 unit_direction = unit_vector(r_in.direction());
@@ -71,10 +71,10 @@ class dielectric : public material {
 
 class lambertian : public material {
     public:
-        lambertian(const vec3& a) : albedo(a) {}
+        lambertian(const color& a) : albedo(a) {}
 
         virtual bool scatter(
-            const ray& r_in, const hit_record& rec, vec3& attenuation, ray& scattered
+            const ray& r_in, const hit_record& rec, color& attenuation, ray& scattered
         ) const  {
             vec3 scatter_direction = rec.normal + random_unit_vector();
             scattered = ray(rec.p, scatter_direction);
@@ -83,16 +83,16 @@ class lambertian : public material {
         }
 
     public:
-        vec3 albedo;
+        color albedo;
 };
 
 
 class metal : public material {
     public:
-        metal(const vec3& a, double f) : albedo(a), fuzz(f < 1 ? f : 1) {}
+        metal(const color& a, double f) : albedo(a), fuzz(f < 1 ? f : 1) {}
 
         virtual bool scatter(
-            const ray& r_in, const hit_record& rec, vec3& attenuation, ray& scattered
+            const ray& r_in, const hit_record& rec, color& attenuation, ray& scattered
         ) const  {
             vec3 reflected = reflect(unit_vector(r_in.direction()), rec.normal);
             scattered = ray(rec.p, reflected + fuzz*random_in_unit_sphere());
@@ -101,7 +101,7 @@ class metal : public material {
         }
 
     public:
-        vec3 albedo;
+        color albedo;
         double fuzz;
 };
 

src/InOneWeekend/hittable.h

@@ -20,13 +20,13 @@ class sphere: public hittable  {
     public:
         sphere() {}
 
-        sphere(vec3 cen, double r, shared_ptr<material> m)
+        sphere(point3 cen, double r, shared_ptr<material> m)
             : center(cen), radius(r), mat_ptr(m) {};
 
         virtual bool hit(const ray& r, double tmin, double tmax, hit_record& rec) const;
 
     public:
-        vec3 center;
+        point3 center;
         double radius;
         shared_ptr<material> mat_ptr;
 };

src/InOneWeekend/main.cc

@@ -27,7 +27,7 @@ class xy_rect: public hittable {
         virtual bool hit(const ray& r, double t0, double t1, hit_record& rec) const;
 
         virtual bool bounding_box(double t0, double t1, aabb& output_box) const {
-            output_box = aabb(vec3(x0,y0, k-0.0001), vec3(x1, y1, k+0.0001));
+            output_box = aabb(point3(x0,y0, k-0.0001), point3(x1, y1, k+0.0001));
             return true;
         }
 
@@ -47,7 +47,7 @@ class xz_rect: public hittable {
         virtual bool hit(const ray& r, double t0, double t1, hit_record& rec) const;
 
         virtual bool bounding_box(double t0, double t1, aabb& output_box) const {
-            output_box = aabb(vec3(x0,k-0.0001,z0), vec3(x1, k+0.0001, z1));
+            output_box = aabb(point3(x0,k-0.0001,z0), point3(x1, k+0.0001, z1));
             return true;
         }
 
@@ -67,7 +67,7 @@ class yz_rect: public hittable {
         virtual bool hit(const ray& r, double t0, double t1, hit_record& rec) const;
 
         virtual bool bounding_box(double t0, double t1, aabb& output_box) const {
-            output_box = aabb(vec3(k-0.0001, y0, z0), vec3(k+0.0001, y1, z1));
+            output_box = aabb(point3(k-0.0001, y0, z0), point3(k+0.0001, y1, z1));
             return true;
         }
 
@@ -89,7 +89,7 @@ bool xy_rect::hit(const ray& r, double t0, double t1, hit_record& rec) const {
     rec.u = (x-x0)/(x1-x0);
     rec.v = (y-y0)/(y1-y0);
     rec.t = t;
-    vec3 outward_normal = vec3(0, 0, 1);
+    auto outward_normal = vec3(0, 0, 1);
     rec.set_face_normal(r, outward_normal);
     rec.mat_ptr = mp;
     rec.p = r.at(t);
@@ -110,7 +110,7 @@ bool xz_rect::hit(const ray& r, double t0, double t1, hit_record& rec) const {
     rec.u = (x-x0)/(x1-x0);
     rec.v = (z-z0)/(z1-z0);
     rec.t = t;
-    vec3 outward_normal = vec3(0, 1, 0);
+    auto outward_normal = vec3(0, 1, 0);
     rec.set_face_normal(r, outward_normal);
     rec.mat_ptr = mp;
     rec.p = r.at(t);
@@ -131,7 +131,7 @@ bool yz_rect::hit(const ray& r, double t0, double t1, hit_record& rec) const {
     rec.u = (y-y0)/(y1-y0);
     rec.v = (z-z0)/(z1-z0);
     rec.t = t;
-    vec3 outward_normal = vec3(1, 0, 0);
+    auto outward_normal = vec3(1, 0, 0);
     rec.set_face_normal(r, outward_normal);
     rec.mat_ptr = mp;
     rec.p = r.at(t);

src/InOneWeekend/material.h

@@ -20,7 +20,7 @@
 class box: public hittable  {
     public:
         box() {}
-        box(const vec3& p0, const vec3& p1, shared_ptr<material> ptr);
+        box(const point3& p0, const point3& p1, shared_ptr<material> ptr);
 
         virtual bool hit(const ray& r, double t0, double t1, hit_record& rec) const;
 
@@ -30,13 +30,13 @@ class box: public hittable  {
         }
 
     public:
-        vec3 box_min;
-        vec3 box_max;
+        point3 box_min;
+        point3 box_max;
         hittable_list sides;
 };
 
 
-box::box(const vec3& p0, const vec3& p1, shared_ptr<material> ptr) {
+box::box(const point3& p0, const point3& p1, shared_ptr<material> ptr) {
     box_min = p0;
     box_max = p1;