RK-4_main

#ifndef MAIN
#define MAIN
#ifdef _WIN32
#include <Windows.h>
#include <GL/GL.h>
#include <GL/GLU.h>
#endif
#ifndef _WIN32
#include <GL/gl.h>
#include <GL/glu.h>
#endif

#include <chrono>

#include "SDL.h"
#include "SDL_opengl.h"
#include "SDL_image.h"
#include "ode.cpp"
#include "thread_pool.cpp"
#define _USE_MATH_DEFINES


#include <SDL_ttf.h>
#include <SDL_image.h>
#pragma comment(lib,"SDL2.lib")
#pragma comment(lib,"SDL2main.lib")
static SDL_Window* window;
static SDL_Renderer* renderer;
#pragma comment(lib,"opengl32.lib")
#pragma comment(lib,"glu32.lib")
#include <shellapi.h>
#pragma comment(lib, "shell32.lib")


static int const screen_size[2] = { 1000, 800 };

using glf = GLfloat;
using point3d = std::array<glf, N>;
using method = RungeKutta; // для выбора численного метода достаточно изменить значение method

double cameraX = 0.0;
double cameraY = 0.0;
const double cameraZ = 20.0;
const double R = 10.0;
double t;
const int number_of_points = 300000;
double dt = 20.0 / 100.0;

// переменные для создания потоков
const int number_of_cores = std::thread::hardware_concurrency();
std::vector<method> attractors;

std::array<point3d, number_of_points> points;
ThreadPool thread_pool(number_of_cores);

int b_val_index = 0;
// красивые формы аттрактора получаются при данных коэффициентах
const int len = 5;
std::array<double, len> b_values = { 0.11, 0.15, 0.215, 0.265, 0.32899 };

double red = 1.0f;
double blue = 1.0f;
double green = 1.0f;

double step_red = 0.05;
double step_blue = 0.025;
double step_green = 0.016;

float x = 16.0;
float y = 16.0;


// для обеспечения работы нескольких потоков, цикл с вызовом численного метода был вынесен в отделтную ф-ию
void process(method& attr, int start, int end, double dt) {
    for (int i = start; i < end; ++i) {
        attr.SetInit({ points[i].at(0), points[i].at(1), points[i].at(2) });
        attr.NextStep(dt);
        points[i] = { static_cast<glf>(attr.getX(0)), static_cast<glf>(attr.getX(1)), static_cast<glf>(attr.getX(2)) };
    }
}

// для каждого потока необходимо создать отдельный объект класса у которого будет вызываться численный метод, в противном случае одна и та же точка может просчитываться в разных потоках
void inittializeAttractors() {
    for (size_t i = 0; i < number_of_cores; ++i)
        attractors.push_back(method());
}


Uint32 callback(Uint32 interval, void* name) {
    //Задаем с период вращения камеры
    std::chrono::time_point<std::chrono::high_resolution_clock> tp = std::chrono::high_resolution_clock::now();
    std::chrono::duration<double, std::micro> dur = tp.time_since_epoch();
    t = dur.count();

    cameraX = R * cos((2 * M_PI) / (60.0 * 1000.0) * (t / 1000.0));
    cameraY = R * sin((2 * M_PI) / (60.0 * 1000.0) * (t / 1000.0));
    // ф-ия enqueue класса ThreadPool отвечает за пробуждение потока при появлении нового запроса на просчет координат точки
    for (size_t i = 0; i < number_of_cores; ++i) {
        thread_pool.enqueue([i] {
            process(std::ref(attractors[i]), i * number_of_points / number_of_cores,
            (i + 1) * number_of_points / number_of_cores, dt);
            });
    }
    return interval;
}

Uint32 colorChange(Uint32 interval, void* name) {
    red += step_red;
    blue += step_blue;
    green += step_green;
    step_red = (red >= 1 || red <= 0) ? -step_red : step_red;
    step_blue = (blue >= 1 || blue <= 0) ? -step_blue : step_blue;
    step_green = (green >= 1 || green <= 0) ? -step_green : step_green;
    return interval;
}

static bool get_input(void) {
    SDL_Event event;
    while (SDL_PollEvent(&event)) {
        switch (event.type) {
        case SDL_QUIT: return false; //The little X in the window got pressed
        case SDL_KEYDOWN:
            if (event.key.keysym.sym == SDLK_ESCAPE) {
                return false;
            }
            if (event.key.keysym.sym == SDLK_w) {
                b_val_index = (b_val_index + 1) % len;
                for (size_t i = 0; i < number_of_cores; ++i)
                    attractors[i].b = b_values[b_val_index];

            }
            if (event.key.keysym.sym == SDLK_s) {
                b_val_index = (b_val_index - 1) % len >= 0 ? (b_val_index - 1) % len : len + (b_val_index - 1) % len;
                for (size_t i = 0; i < number_of_cores; ++i)
                    attractors[i].b = b_values[b_val_index];

            }
            std::cout << b_values[b_val_index] << '\n';
            break;
        }
    }
    return true;
}




static void draw(void) {
    //Clear the screen's color and depth (default color is black, but can change with glClearColor(...))
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    //Drawing to an area starting at the bottom left, screen_size[0] wide, and screen_size[1] high.
    glViewport(0, 0, screen_size[0], screen_size[1]);
    //OpenGL is a state machine.  Tell it that future commands changing the matrix are to change OpenGL's projection matrix
    glMatrixMode(GL_PROJECTION);
    //Reset the projection matrix
    glLoadIdentity();
    //Multiply a perspective projection matrix into OpenGL's projection matrix
    gluPerspective(45.0, (double)(screen_size[0]) / (double)(screen_size[1]), 0.1, 100.0);

    //Tell OpenGL that future commands changing the matrix are to change the modelview matrix
    glMatrixMode(GL_MODELVIEW);
    //Reset the modelview matrix
    glLoadIdentity();
    //Multiply OpenGL's modelview matrix with a transform matrix that simulates a camera at (2,3,4) looking towards the location (0,0,0) with up defined to be (0,1,0)

    gluLookAt(cameraX, cameraY, cameraZ, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0);
    //gluLookAt(-20.0f, -15.0f, 20.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glColor3f(red, blue, green); // Set the color to white
    //int ind = 6;
    //glColor3f(colors[ind].at(0), colors[ind].at(1), colors[ind].at(2)); // Set the color to white
    glBegin(GL_POINTS);

    for (size_t i = 0; i < number_of_points; i++) {
        glVertex3f(points[i].at(0), points[i].at(1), points[i].at(2));
    }

    glEnd();

    //OpenGL works best double-buffered.  SDL automatically sets that up for us.  This will draw what we have
    //  just drawn to the screen so that we can see it.
    SDL_GL_SwapWindow(window);
}

int main(int argc, char* argv[]) {
    //TTF_Init();
    inittializeAttractors();
    //считываем заготовленные точки из файла
    std::ifstream in("prep.txt");
    if (in.is_open()) {
        glf x, y, z;
        int check = 0;
        while (in >> x >> y >> z && check < number_of_points) {
            points[check] = { x, y, z };
            check++;
        }
    }
    in.close();
    //Initialize everything, but don't catch fatal signals; give them to the OS.
    SDL_Init(SDL_INIT_EVERYTHING | SDL_INIT_NOPARACHUTE);



    //Creates the window
    window = SDL_CreateWindow("Thomas' cyclically symmetric attractor", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, screen_size[0], screen_size[1], SDL_WINDOW_OPENGL | SDL_WINDOW_ALLOW_HIGHDPI);
    //Create an OpenGL context.  In SDL 1, this was done automatically.
    SDL_GLContext context = SDL_GL_CreateContext(window);

    //We now have an OpenGL context, and can call OpenGL functions.



    //Objects need to test each other to see which one is in front.  If you don't do this, you'll "see through" things!
    glEnable(GL_DEPTH_TEST);

    SDL_TimerID timerID = SDL_AddTimer(20, callback, const_cast<char*>("SDL"));
    SDL_TimerID timerID_color = SDL_AddTimer(1000, colorChange, const_cast<char*>("SDL"));
    // Clean up

    //Main application loop
    while (true) {
        if (!get_input()) break;
        draw();

    }
    //Мы можем отрисовать наш текст, как и любую другую текстуру, так как
    //он был отрендерен в текстуру


    SDL_RemoveTimer(timerID);
    SDL_RemoveTimer(timerID_color);

    //Clean up


    SDL_GL_DeleteContext(context);
    SDL_DestroyWindow(window);
    //TTF_Quit();
    SDL_Quit();

    //Return success; program exits
    return 0;
}

#endif // !MAIN