RayTracing/RayTracer.cpp at master · EsteBran/RayTracing · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
// RayTracer.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include "utility.h"
#include "color.h"
#include "hittable_list.h"
#include "sphere.h"
#include "camera.h"
#include "material.h"
#include <iostream>

using namespace std;


//returns color of ray (colour of pixel)
color ray_color(const ray& r, const hittable& world, int depth) {
    hit_record rec;

    //defines how many times ray_color function will recurse
    if (depth <= 0) {
        return color(0, 0, 0);
    }

    //return normal vector as colour
    if (world.hit(r, 0.001, infinity, rec)) {
        ray scattered;
        color attenuation;
        if (rec.mat_ptr->scatter(r, rec, attenuation, scattered)) {
            return attenuation * ray_color(scattered, world, depth - 1);
        }
        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) * color(1.0, 1.0, 1.0) + t * color(0.5, 0.7, 1.0); //lerp for sky
}


int main()
{
   //Image
    const auto aspect_ratio = 16.0 / 9.0;
    const int image_width = 800;
    const int image_height = static_cast<int>(image_width / aspect_ratio);
    const int samples_per_pixel = 100;
    const int max_depth = 50;

    //world
    auto R = cos(pi / 4);
    hittable_list world;
    auto material_ground = make_shared<lambertian>(color(0.8, 0.8, 0.0));
    auto material_center = make_shared<lambertian>(color(0.1, 0.2, 0.5));
    auto material_left = make_shared<refract>(1.5);
    auto material_right = make_shared<metal>(color(0.8, 0.6, 0.2), 0.0);

    world.add(make_shared<sphere>(point3(0.0, -100.5, -1.0), 100.0, material_ground));
    world.add(make_shared<sphere>(point3(0.0, 0.0, -1.0), 0.5, material_center));
    world.add(make_shared<sphere>(point3(-1.0, 0.0, -1.0), 0.5, material_left));
    world.add(make_shared<sphere>(point3(-1.0, 0.0, -1.0), -0.45, material_left));
    world.add(make_shared<sphere>(point3(1.0, 0.0, -1.0), 0.5, material_right));


    //Camera
    point3 lookfrom(3, 3, 2);
    point3 lookat(0, 0, -1);
    vec3 vup(0, 1, 0);
    auto dist_to_focus = 5.1;
    auto aperture = 0.1;

    camera cam(lookfrom, lookat, vup, 20, aspect_ratio, aperture, dist_to_focus);


    // Render
    cout << "P3\n" << image_width << ' ' << image_height << "\n255\n";
    for (int j = image_height - 1; j >= 0; --j) {
        cerr << "\rscanlines remaining: " << j << ' ' << flush;
        for (int i = 0; i < image_width; ++i) {
            color pixel_color(0, 0, 0);
            for (int s = 0; s < samples_per_pixel; ++s) {
                //jitters ray by random amount to get antialiasing
                auto u = (i + random_double()) / (image_width - 1);
                auto v = (j + random_double()) / (image_height - 1);
                ray r = cam.get_ray(u, v);
                pixel_color += ray_color(r, world, max_depth);
            }
            write_color(std::cout, pixel_color, samples_per_pixel);
        }
    }

    cerr << "\ndone.\n";
}