update todo

README.md

@@ -13,9 +13,10 @@ https://www.linuxhowtos.org/C_C++/socket.htm
 * [x] waits for connection
 * [x] send a message to the client
 * [x] move core rendering out of main.cpp
-* [ ] combine 'hittable' 'hittable_list' and 'scene' into 'world'
+* [x] combine 'hittable' 'hittable_list' and 'scene' in 'world'
 * [x] send rendered image data to client
 * [x] form image file on client
+* [ ] extract netcode from main
 * [ ] specify protocol format
 * [ ] receive imaging command
 * [x] render image

include/colour.h

@@ -1,6 +1,7 @@
 #pragma once
 
-#include "rtweekend.h"
+#include "error.h"
+#include "vec3.h"
 
 // for writing to stdout
 #include <iostream>
@@ -8,59 +9,21 @@
 // for writing to socket
 #include <unistd.h>
 
+class colour : public vec3
+{
+    using vec3::vec3;
+
+public:
+    friend colour operator*(const colour& u, const colour& v);
+    friend colour lerp(const colour& a, const colour& b, double t);
+
+    colour correct_gamma(int samples);
+
+    friend void write_colour_to_socket(int sockfd, colour pixel_colour, int samples_per_pixel);
+    friend void write_colour_to_stream(std::ostream &out, colour pixel_colour, int samples_per_pixel);
+    friend int format_component(double component);
+};
+
 const colour pink(254.0/255.0, 226.0/255.0, 170.0/255.0);
 const colour grey(0.133, 0.133, 0.133);
 
-void correct_gamma(colour& pixel_colour, int samples)
-{
-    double r = pixel_colour.x();
-    double g = pixel_colour.y();
-    double b = pixel_colour.z();
-
-    // divide the colour total by the number of samples and gamma-correct for gamma=2.0
-    auto scale = 1.0 / samples;
-    r = sqrt(scale * r);
-    g = sqrt(scale * g);
-    b = sqrt(scale * b);
-
-    pixel_colour = colour(r, g, b);
-}
-
-int format_component(double component)
-{
-    return int(256 * math::clamp(component, 0.0, 0.999));
-}
-
-void write_colour_to_stream(std::ostream &out, colour pixel_colour, int samples_per_pixel)
-{
-    correct_gamma(pixel_colour, samples_per_pixel);
-
-    auto r = pixel_colour.x();
-    auto g = pixel_colour.y();
-    auto b = pixel_colour.z();
-    
-    // write the translated [0,255] value of each colour component.
-    out << format_component(r) << ' '
-        << format_component(g) << ' '
-        << format_component(b) << '\n';
-}
-
-void write_colour_to_socket(int sockfd, colour pixel_colour, int samples_per_pixel)
-{
-    correct_gamma(pixel_colour, samples_per_pixel);
-
-    int r = format_component(pixel_colour.x());
-    int g = format_component(pixel_colour.y());
-    int b = format_component(pixel_colour.z());
-
-    // pack values
-    int len = 3;
-    char s[len];
-    sprintf(s, "%c%c%c", r, g, b);
-
-    int written = write(sockfd, s, len);
-    if (written < 0)
-    {
-        error("ERROR writing colour to socket");
-    }
-}

include/error.h

@@ -1,7 +1,5 @@
+#pragma once
+
 #include <iostream>
 
-void error(const char* message)
-{
-    perror(message);
-    exit(1);
-}
+void error(const char* message);

include/hit_record.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <cmath>
+#include <cstdlib>
+#include <limits>
+#include <memory>
+
+class material;
+
+struct hit_record
+{
+    point3                      p;
+    vec3                        normal;
+    std::shared_ptr<material>   mat_ptr;
+    double                      t;
+    bool                        front_face;
+
+    inline void set_face_normal(const ray& r, const vec3& outward_normal)
+    {
+        front_face = dot(r.direction(), outward_normal) < 0;
+        normal = front_face ? outward_normal : -outward_normal;
+    }
+};

include/hittable.h

@@ -1,27 +1,10 @@
 #pragma once
 
-#include "rtweekend.h"
 #include "ray.h"
-
-class material;
-
-struct hit_record
-{
-    point3                  p;
-    vec3                    normal;
-    shared_ptr<material>    mat_ptr;
-    double                  t;
-    bool                    front_face;
-
-    inline void set_face_normal(const ray& r, const vec3& outward_normal)
-    {
-        front_face = dot(r.direction(), outward_normal) < 0;
-        normal = front_face ? outward_normal : -outward_normal;
-    }
-};
+#include "hit_record.h"
 
 class hittable
 {
-    public:
+public:
     virtual bool hit(const ray& r, double tMin, double tMax, hit_record& rec) const = 0;
 };

include/hittable_list.h

@@ -20,21 +20,3 @@ class hittable_list : public hittable
         std::vector<std::shared_ptr<hittable>> objects_;
 };
 
-bool hittable_list::hit(const ray& r, double t_min, double t_max, hit_record& rec) const
-{
-    hit_record temp_rec;
-    bool hit_anything = false;
-    auto closest_so_far = t_max;
-
-    for (const auto& object : objects_)
-    {
-        if (object->hit(r, t_min, closest_so_far, temp_rec))
-        {
-            hit_anything = true;
-            closest_so_far = temp_rec.t;
-            rec = temp_rec;
-        }
-    }
-
-    return hit_anything;
-}

include/material.h

@@ -1,7 +1,7 @@
 #pragma once
 
-#include "rtweekend.h"
 #include "hittable.h"
+#include "hit_record.h"
 
 class material
 {
@@ -13,13 +13,6 @@ class material
             ray& scattered) const = 0;
 };
 
-double schlick(double cosine, double refraction_index)
-{
-    auto r0 = (1-refraction_index) / (1+refraction_index);
-    r0 = r0*r0;
-    return r0 + (1-r0)*pow(1-cosine, 5);
-}
-
 class lambertian : public material
 {
     public:
@@ -106,4 +99,11 @@ class dielectric : public material
 
     private:
         double refraction_index_;
+
+        double schlick(double cosine, double refraction_index) const
+        {
+            auto r0 = (1-refraction_index) / (1+refraction_index);
+            r0 = r0*r0;
+            return r0 + (1-r0)*pow(1-cosine, 5);
+        }
 };

include/rtweekend.h

@@ -1,18 +0,0 @@
-#pragma once
-
-#include <cmath>
-#include <cstdlib>
-#include <limits>
-#include <memory>
-
-// usings
-
-using std::shared_ptr;
-using std::make_shared;
-using std::sqrt;
-
-// common headers
-
-#include "error.h"
-#include "ray.h"
-#include "vec3.h"

include/scene.h

@@ -1,100 +0,0 @@
-#pragma once
-
-#include "math.h"
-#include "sphere.h"
-#include "colour.h"
-#include "material.h"
-#include "hittable.h"
-#include "hittable_list.h"
-
-colour ray_colour(const ray& r, const hittable& world, int depth)
-{
-    hit_record rec;
-    if (depth <= 0)
-    {
-        return grey;
-    }
-
-    if (world.hit(r, 0.001, math::infinity, rec))
-    {
-        ray     scattered;
-        colour  attenuation;
-
-        if (rec.mat_ptr->scatter(r, rec, attenuation, scattered))
-        {
-            return attenuation * ray_colour(scattered, world, depth-1);
-        }
-
-        return grey;
-    }
-
-    vec3 unit_direction = normalize(r.direction());
-    auto t = 0.5 * (unit_direction.y() + 1.0) + 0.5;
-
-    return lerp(grey, pink, t);
-}
-
-hittable_list random_scene()
-{
-    hittable_list world;
-
-
-    //auto ground_material = make_shared<lambertian>(pink);
-    //world.add(make_shared<sphere>(point3(0,-1000,0), 1000, ground_material));
-
-    //for (int a = -11; a < 11; a++)
-    //{
-    //    for (int b = -11; b < 11; b++)
-    //    {
-    //        auto choose_mat = random_double();
-    //        point3 centre(a + 0.9*random_double(), 0.2, b + 0.9*random_double());
-
-    //        if ((centre - point3(4, 0.2, 0)).length() > 0.9)
-    //        {
-    //            shared_ptr<material> sphere_material;
-
-    //            if (choose_mat < 0.8)
-    //            {
-    //                // diffuse
-    //                //auto albedo = colour::random() * colour::random();
-    //                sphere_material = make_shared<lambertian>(pink);
-    //                world.add(make_shared<sphere>(centre, 0.2, sphere_material));
-    //            }
-    //            else if (choose_mat < 0.95)
-    //            {
-    //                // metal
-    //                auto fuzz = random_double(0, 0.5);
-    //                sphere_material = make_shared<metal>(pink, fuzz);
-    //                world.add(make_shared<sphere>(centre, 0.2, sphere_material));
-    //            }
-    //            else
-    //            {
-    //                // glass
-    //                sphere_material = make_shared<dielectric>(1.5);
-    //                world.add(make_shared<sphere>(centre,0.2, sphere_material));
-    //            }
-    //        }
-    //    }
-    //}
-
-    auto material1 = make_shared<dielectric>(1.5);
-    world.add(make_shared<sphere>(point3(0, 0, 0), 3.0, material1));
-
-    //auto material2 = make_shared<lambertian>(pink);
-    //world.add(make_shared<sphere>(point3(-4, 1, 0), 1.0, material2));
-    
-    auto material3 = make_shared<metal>(pink, 0.5);
-    int sphere_count = 10;
-    for (int i = 0; i < sphere_count; i++)
-    {
-        float a = 6.28 * (float)i/sphere_count - 100.0;
-        float r = 8.0;
-        float x = r*sin(a);
-        float y = 2.0*cos(a);
-        float z = r*cos(a);
-        point3 pos(x,y,z);
-        world.add(make_shared<sphere>(pos, 2.0, material3));
-    }
-
-    return world;
-}

include/sphere.h

@@ -7,7 +7,7 @@ class sphere : public hittable
 {
     public:
         sphere() {}
-        sphere(point3 centre, double r, shared_ptr<material> m) : 
+        sphere(point3 centre, double r, std::shared_ptr<material> m) : 
             centre_(centre), 
             radius_(r),
             mat_ptr_(m)
@@ -18,47 +18,6 @@ class sphere : public hittable
     private:
         point3                      centre_;
         double                      radius_;
-        shared_ptr<material>    mat_ptr_;
+        std::shared_ptr<material>   mat_ptr_;
 };
 
-bool sphere::hit(const ray& r, double t_min, double t_max, hit_record& rec) const 
-{
-    vec3 oc = r.origin() - centre_;
-    auto a = r.direction().length_squared();
-    auto half_b = dot(oc, r.direction());
-    auto c = oc.length_squared() - radius_*radius_;
-    auto discriminant = half_b*half_b - a*c;
-
-    if (discriminant > 0)
-    {
-        auto root = sqrt(discriminant);
-
-        auto temp = (-half_b - root)/a;
-        if (temp < t_max && temp > t_min)
-        {
-            rec.t = temp;
-            rec.p = r.at(rec.t);
-
-            vec3 outward_normal = (rec.p - centre_) / radius_;
-            rec.set_face_normal(r, outward_normal);
-            rec.mat_ptr = mat_ptr_;
-
-            return true;
-        }
-
-        temp = (-half_b + root) / a;
-        if (temp < t_max && temp > t_min)
-        {
-            rec.t = temp;
-            rec.p = r.at(rec.t);
-            
-            vec3 outward_normal = (rec.p - centre_) / radius_;
-            rec.set_face_normal(r, outward_normal);
-            rec.mat_ptr = mat_ptr_;
-            
-            return true;
-        }
-    }
-
-    return false;
-}

include/vec3.h

@@ -52,5 +52,4 @@ private:
 
 // type aliases for vec3
 using point3 = vec3; // 3D point
-using colour = vec3; // RGB colour
 

include/world.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include "math.h"
+#include "sphere.h"
+#include "colour.h"
+#include "material.h"
+#include "hittable_list.h"
+
+class world : public hittable_list
+{
+public:
+    static world* close_glass_sphere();
+    static world* orb_field();
+
+    friend colour trace(const world& world, const ray& ray, int depth);
+};
+

src/colour.cpp

@@ -0,0 +1,67 @@
+#include "colour.h"
+
+colour colour::correct_gamma(int samples)
+{
+    double r = x();
+    double g = y();
+    double b = z();
+
+    // divide the colour total by the number of samples and gamma-correct for gamma=2.0
+    auto scale = 1.0 / samples;
+    r = sqrt(scale * r);
+    g = sqrt(scale * g);
+    b = sqrt(scale * b);
+
+    return colour(r, g, b);
+}
+
+int format_component(double component)
+{
+    return int(256 * math::clamp(component, 0.0, 0.999));
+}
+
+void write_colour_to_socket(int sockfd, colour pixel_colour, int samples_per_pixel)
+{
+    pixel_colour = pixel_colour.correct_gamma(samples_per_pixel);
+
+    int r = format_component(pixel_colour.x());
+    int g = format_component(pixel_colour.y());
+    int b = format_component(pixel_colour.z());
+
+    // pack values
+    int len = 3;
+    char s[len];
+    sprintf(s, "%c%c%c", r, g, b);
+
+    int written = write(sockfd, s, len);
+    if (written < 0)
+    {
+        error("ERROR writing colour to socket");
+    }
+}
+
+void write_colour_to_stream(std::ostream &out, colour pixel_colour, int samples_per_pixel)
+{
+    pixel_colour = pixel_colour.correct_gamma(samples_per_pixel);
+
+    auto r = pixel_colour.x();
+    auto g = pixel_colour.y();
+    auto b = pixel_colour.z();
+    
+    // write the translated [0,255] value of each colour component.
+    out << format_component(r) << ' '
+        << format_component(g) << ' '
+        << format_component(b) << '\n';
+}
+
+colour operator*(const colour& u, const colour& v)
+{
+    vec3 value = (vec3)u * (vec3)v;
+    return colour(value.x(), value.y(), value.z());
+}
+
+colour lerp(const colour& a, const colour& b, double t)
+{
+    vec3 value = lerp((vec3)a, (vec3)b, t);
+    return colour(value.x(), value.y(), value.z());
+}

src/error.cpp

@@ -0,0 +1,7 @@
+#include "error.h"
+
+void error(const char* message)
+{
+    perror(message);
+    exit(1);
+}

src/foo.cpp

@@ -1 +0,0 @@
-#include "foo.h"

src/hittable_list.cpp

@@ -0,0 +1,20 @@
+#include "hittable_list.h"
+
+bool hittable_list::hit(const ray& r, double t_min, double t_max, hit_record& rec) const
+{
+    hit_record temp_rec;
+    bool hit_anything = false;
+    auto closest_so_far = t_max;
+
+    for (const auto& object : objects_)
+    {
+        if (object->hit(r, t_min, closest_so_far, temp_rec))
+        {
+            hit_anything = true;
+            closest_so_far = temp_rec.t;
+            rec = temp_rec;
+        }
+    }
+
+    return hit_anything;
+}

src/main.cpp

@@ -1,14 +1,10 @@
-#include "rtweekend.h"
-
-#include "scene.h"
-
 #include "colour.h"
 #include "camera.h"
 #include "material.h"
 #include "image.h"
+#include "world.h"
 
 #include <iostream>
-
 #include <string.h>
 
 #include <unistd.h>
@@ -106,7 +102,7 @@ void send_image_dimensions(int sock, unsigned int width, unsigned int height)
     }
 }
 
-void render(camera& cam, hittable_list& world, int client_sock)
+void render(camera& cam, const world& world, int client_sock)
 {
     for (int j = HEIGHT - 1; j >= 0; --j)
     {
@@ -120,7 +116,7 @@ void render(camera& cam, hittable_list& world, int client_sock)
                 auto u = (i + math::random_double()) / (WIDTH-1);
                 auto v = (j + math::random_double()) / (HEIGHT-1);
                 ray r = cam.get_ray(u, v);
-                pixel_colour += ray_colour(r, world, MAX_DEPTH);
+                pixel_colour += trace(world, r, MAX_DEPTH);
             }
 
             // TODO: we should instead write our output to some buffer in memory
@@ -142,8 +138,6 @@ int main()
 
     //std::cout << "P3\n" << WIDTH << ' ' << HEIGHT << "\n255\n";
 
-    hittable_list world = random_scene();
-
     auto dist_to_target = 10.0;
     auto dist_to_focus = dist_to_target + 1.0;
     auto cam_y = 1.0;
@@ -154,7 +148,9 @@ int main()
 
     camera cam(lookfrom, lookat, vup, 47, ASPECT_RATIO, aperture, dist_to_focus);
 
-    render(cam, world, newsockfd);
+    const world* world = world::close_glass_sphere();
+
+    render(cam, *world, newsockfd);
 
     // close client socket
     close(newsockfd);

src/sphere.cpp

@@ -0,0 +1,43 @@
+#include "sphere.h"
+
+bool sphere::hit(const ray& r, double t_min, double t_max, hit_record& rec) const 
+{
+    vec3 oc = r.origin() - centre_;
+    auto a = r.direction().length_squared();
+    auto half_b = dot(oc, r.direction());
+    auto c = oc.length_squared() - radius_*radius_;
+    auto discriminant = half_b*half_b - a*c;
+
+    if (discriminant > 0)
+    {
+        auto root = sqrt(discriminant);
+
+        auto temp = (-half_b - root)/a;
+        if (temp < t_max && temp > t_min)
+        {
+            rec.t = temp;
+            rec.p = r.at(rec.t);
+
+            vec3 outward_normal = (rec.p - centre_) / radius_;
+            rec.set_face_normal(r, outward_normal);
+            rec.mat_ptr = mat_ptr_;
+
+            return true;
+        }
+
+        temp = (-half_b + root) / a;
+        if (temp < t_max && temp > t_min)
+        {
+            rec.t = temp;
+            rec.p = r.at(rec.t);
+            
+            vec3 outward_normal = (rec.p - centre_) / radius_;
+            rec.set_face_normal(r, outward_normal);
+            rec.mat_ptr = mat_ptr_;
+            
+            return true;
+        }
+    }
+
+    return false;
+}

src/world.cpp

@@ -0,0 +1,54 @@
+#include "world.h"
+
+colour trace(const world& world, const ray& r, int depth)
+{
+    hit_record rec;
+    if (depth <= 0)
+    {
+        return grey;
+    }
+
+    if (world.hit(r, 0.001, math::infinity, rec))
+    {
+        ray     scattered;
+        colour  attenuation;
+
+        if (rec.mat_ptr->scatter(r, rec, attenuation, scattered))
+        {
+            return attenuation * trace(world, scattered, depth-1);
+        }
+
+        return grey;
+    }
+
+    vec3 unit_direction = normalize(r.direction());
+    auto t = 0.5 * (unit_direction.y() + 1.0) + 0.5;
+
+    return lerp(grey, pink, t);
+}
+
+world* world::close_glass_sphere()
+{
+    world* w = new world();
+
+    auto material1 = std::make_shared<dielectric>(1.5);
+    w->add(std::make_shared<sphere>(point3(0, 0, 0), 3.0, material1));
+
+    //auto material2 = make_shared<lambertian>(pink);
+    //world.add(make_shared<sphere>(point3(-4, 1, 0), 1.0, material2));
+    
+    auto material3 = std::make_shared<metal>(pink, 0.5);
+    int sphere_count = 10;
+    for (int i = 0; i < sphere_count; i++)
+    {
+        float a = 6.28 * (float)i/sphere_count - 100.0;
+        float r = 8.0;
+        float x = r*sin(a);
+        float y = 2.0*cos(a);
+        float z = r*cos(a);
+        point3 pos(x,y,z);
+        w->add(std::make_shared<sphere>(pos, 2.0, material3));
+    }
+
+    return w;
+}