aboutsummaryrefslogtreecommitdiffstats
path: root/main.cpp
blob: 034aefa2ec85a655fc450fb208b0f4116659ffd9 (plain)
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
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
constexpr unsigned Width = 1000;
constexpr double   Aspect = 16.0 / 9.0;
constexpr unsigned Height = Width / Aspect;
constexpr unsigned Threads = 8;

#include "color.h"
#include "ray.h"
#include "renderer.h"
#include "sphere.h"
#include "vec3.h"
#include "view.h"
#include "world.h"

#include "imgui.h"
#include "imgui_impl_sdl2.h"
#include "imgui_impl_sdlrenderer2.h"
#include <SDL2/SDL.h>

#include <algorithm>
#include <chrono>
#include <cstring>
#include <iostream>
#include <ranges>
#include <thread>

static World world;

static View Camera;
static int SamplesPerPixel = 20;
static std::unique_ptr<Renderer<Threads>> renderer;
static std::chrono::time_point<std::chrono::high_resolution_clock> renderStart;
static std::chrono::duration<double> renderTime;

static color ray_color(const ray& r, int depth = 50);
static void initiateRender(SDL_Surface *canvas);

int main()
{
    SDL_Init(SDL_INIT_VIDEO);
    auto window = SDL_CreateWindow("raytrace", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, Width, Height, SDL_WINDOW_RESIZABLE);
    auto canvas = SDL_CreateRGBSurfaceWithFormat(0, Width, Height, 32, SDL_PIXELFORMAT_RGBA8888);
    auto painter = SDL_CreateRenderer(window, -1, SDL_RENDERER_PRESENTVSYNC /*| SDL_RENDERER_ACCELERATED*/);

    ImGui::CreateContext();
    ImGui_ImplSDL2_InitForSDLRenderer(window, painter);
    ImGui_ImplSDLRenderer2_Init(painter);

    world.add(point3( 0.00, -100.50, -1.0), 100.0, Material::Lambertian, color(0.5, 1.0, 0.5));
    world.add(point3(-0.50,    0.00, -1.2),   0.5, Material::Dielectric, color(1.0, 0.8, 0.8));
    world.add(point3( 0.50,    0.00, -1.0),   0.5, Material::Metal,      color(0.5, 0.5, 0.5));
    world.add(point3(-0.05,   -0.35, -0.7),   0.1, Material::Metal,      color(0.8, 0.6, 0.0));

    std::cout << "Spawning threads..." << std::endl;
    initiateRender(canvas);

    std::cout << "Entering render..." << std::endl;
    bool run = true;
    for (SDL_Event event; run;) {
        while (SDL_PollEvent(&event)) {
            ImGui_ImplSDL2_ProcessEvent(&event);
            if (event.type == SDL_QUIT) {
                renderer->stop();
                run = false;
            }
        }

        ImGui_ImplSDLRenderer2_NewFrame();
        ImGui_ImplSDL2_NewFrame();
        ImGui::NewFrame();

        ImGui::Begin("settings", nullptr, ImGuiWindowFlags_AlwaysAutoResize);
        ImGui::SliderFloat("fov", &Camera.fieldOfView, 10, 160);
        ImGui::SetNextItemWidth(100); ImGui::InputDouble("X", &Camera.camera.x(), 0.1, 0.05, "%.2lf");
        ImGui::SameLine(); ImGui::SetNextItemWidth(100); ImGui::InputDouble("Y", &Camera.camera.y(), 0.1, 0.05, "%.2lf");
        ImGui::SameLine(); ImGui::SetNextItemWidth(100); ImGui::InputDouble("Z", &Camera.camera.z(), 0.1, 0.05, "%.2lf");
        ImGui::SliderInt("samples", &SamplesPerPixel, 1, 200);
        if (ImGui::Button("recalculate")) {
            initiateRender(canvas);
        }
        ImGui::SameLine();
        if (ImGui::Button("exit")) {
            renderer->stop();
            run = false;
        }
        if (*renderer) {
            ImGui::SameLine();
            if (ImGui::Button("stop")) {
                renderer->stop();
            }
            ImGui::Text("wait... %u%%", renderer->progress());
        } else if (renderTime == std::chrono::duration<double>::zero()) {
            renderTime = std::chrono::high_resolution_clock::now() - renderStart;
        } else {
            ImGui::Text("%0.6lfs", renderTime.count());
        }
        ImGui::End();

        ImGui::Begin("balls", nullptr, ImGuiWindowFlags_AlwaysAutoResize); {
            char radius[] = "radius 0";
            char mat[] = "mat 0";
            char xpos[] = "x 0";
            char ypos[] = "y 0";
            char zpos[] = "z 0";
            for (auto& o : std::views::drop(world.objects, 1)) {
                ImGui::Combo(mat, reinterpret_cast<int *>(&o.M), "Lambertian\0Metal\0Dielectric\0");
                ImGui::SameLine(); ImGui::SetNextItemWidth(100); ImGui::InputDouble(radius, &o.radius, 0.1, 0.05, "%.2lf");
                ImGui::SetNextItemWidth(100); ImGui::InputDouble(xpos, &o.center.x(), 0.05, 0.05, "%.2lf");
                ImGui::SameLine(); ImGui::SetNextItemWidth(100); ImGui::InputDouble(ypos, &o.center.y(), 0.1, 0.05, "%.2lf");
                ImGui::SameLine(); ImGui::SetNextItemWidth(100); ImGui::InputDouble(zpos, &o.center.z(), 0.1, 0.05, "%.2lf");
                radius[7]++;
                mat[4]++;
                xpos[2]++;
                ypos[2]++;
                zpos[2]++;
            }
        } ImGui::End();

        auto tex = SDL_CreateTextureFromSurface(painter, canvas);

        ImGui::Render();
        SDL_RenderClear(painter);
        SDL_RenderCopy(painter, tex, nullptr, nullptr);
        ImGui_ImplSDLRenderer2_RenderDrawData(ImGui::GetDrawData());
        SDL_RenderPresent(painter);
        SDL_DestroyTexture(tex);

        std::this_thread::sleep_for(std::chrono::milliseconds(30));
    }

    ImGui_ImplSDLRenderer2_Shutdown();
    ImGui_ImplSDL2_Shutdown();
    ImGui::DestroyContext();

    SDL_FreeSurface(canvas);
    SDL_DestroyRenderer(painter);
    SDL_DestroyWindow(window);
    SDL_Quit();
}

color ray_color(const ray& r, int depth)
{
    if (depth <= 0)
        return {};

    if (auto hit = world.hit(r); hit) {
        const auto& [closest, sphere] = *hit;
        const auto [atten, scat] = sphere.scatter(r, closest);
        return atten * ray_color(scat, depth - 1);
    } else {
        const auto unitDir = r.direction().normalize();
        const auto a = 0.5 * (unitDir.y() + 1.0);
        return (1.0 - a) * color(1.0, 1.0, 1.0) + a * color(0.5, 0.7, 1.0);
    }
}

void initiateRender(SDL_Surface *canvas)
{
    renderStart = std::chrono::high_resolution_clock::now();
    renderTime = std::chrono::duration<double>::zero();

    auto func = [format = canvas->format](auto x, auto y, auto pbuf) {
        auto col = std::ranges::fold_left(std::views::iota(0, SamplesPerPixel), color(),
            [y, x](color c, int i) { return c + ray_color(Camera.getRay(x, y, true)); });

        col = col / SamplesPerPixel * 255;
        pbuf[y * Width + x] = SDL_MapRGBA(format, col.x(), col.y(), col.z(), 255);
    };

    Camera.recalculate();
    renderer.reset(new Renderer<Threads>(func, Width, Height, (uint32_t *)canvas->pixels));
}