Slime-Simulation/src/main.cpp

#include <SDL2/SDL.h>

#include <iostream>
#include <vector>
#include <chrono>
#include <math.h>
#include <stdlib.h>
#include <time.h>

#include "Field.hpp"
#include "Agent.hpp"

unsigned long long SYS_TIME_US()
{
    return (unsigned long long)(std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::system_clock::now().time_since_epoch()).count());
}

int main(int argc, char* argv[])
{
    srand(time(0));
    int width, height;

    if (argc == 1)
    {
        width = height = 300;
    }
    else
    {
        width = atoi(argv[1]);
        height = atoi(argv[2]);
    }

    if (SDL_Init(SDL_INIT_VIDEO) < 0)
    {
        std::cout << "Video Init Error." << std::endl;
    }

    SDL_Window* window = SDL_CreateWindow("Slime Mold Simulator", SDL_WINDOWPOS_CENTERED-width/2, SDL_WINDOWPOS_CENTERED-height/2, width, height, SDL_WINDOW_SHOWN);

    SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_TARGETTEXTURE);


    SDL_Texture* field_texture = SDL_CreateTexture(renderer, SDL_GetWindowPixelFormat(window), SDL_TEXTUREACCESS_TARGET, width, height);

    Field field(width, height, 1.0f);

    std::vector<Agent*> agents;

    bool* start_positions = new bool[width*height];
    for(int i = 0; i < width*height; i++)
    {
        start_positions[i] = false;
    }

    int created = 0;
    int index = 0;
    int max_count = (int)sqrt(width*height)*10;
    while(created < max_count)
    {
        int rng_cur = rand()%(width*height/max_count);
        if (rng_cur == 0 && !start_positions[index])
        {
            start_positions[index] = true;
            created++;
        }

        index = (index+1)%(width*height);
    }

    for(int i = 0; i < width*height; i++)
    {
        if (start_positions[i])
        {
            Agent* next_agent = new Agent((float)(i%width), (float)(i/width), (float)width, (float)height, 2.0f*M_PI*((float)(rand()%100)/100.0f), 0.8f, 0.1f,3.0f);
            agents.push_back(next_agent);

            field.add_pheromone((float)(i%width),(float)(i/width), 0.8f);
        }
    }

    delete[] start_positions;

    SDL_Rect screen_rect = {0,0,width,height};

    unsigned long long time_old, time_now;
    time_now = time_old = SYS_TIME_US();

    int iteration_duration = 16666/10;
    int max_loops = 10000000/iteration_duration;
    bool pause = true;

    while(true)
    {
        SDL_Event event;
        if (1 == SDL_PollEvent(&event))
        {
            if (event.type == SDL_KEYDOWN)
            {
                if (event.key.keysym.scancode == SDL_SCANCODE_Q)
                {
                    break;
                }
                else if (event.key.keysym.scancode == SDL_SCANCODE_P)
                {
                    pause = !pause;
                }
            }
        }

        time_now = SYS_TIME_US();
        if (time_now >= time_old + iteration_duration)
        {
            time_old = time_now;
            if (pause)
            {
                continue;
            }

            field.tick();
            for(unsigned int i = 0; i < agents.size(); i++)
            {
                agents[i]->tick(&field);
            }

            SDL_SetRenderTarget(renderer, field_texture);
            SDL_SetRenderDrawColor(renderer, 0,0,0,0);
            SDL_RenderClear(renderer);

            float max_strength = field.get_pheromone_max();

            for (int x = 0; x < width; x++)
            {
                for (int y = 0; y < height; y++)
                {
                    float cur_strength = field.get_pheromone_strength(x, y);
    
                    int color_val = std::max(0,std::min(255,(int)(255.0f * cur_strength / max_strength)));
                    SDL_SetRenderDrawColor(renderer, color_val, color_val, color_val, 0xFF);

                    SDL_RenderDrawPoint(renderer, x, y);
                }
            }

            SDL_SetRenderTarget(renderer, NULL);
            SDL_SetRenderDrawColor(renderer, 0,0,0,0);
            SDL_RenderClear(renderer);

            SDL_RenderCopy(renderer, field_texture, &screen_rect, &screen_rect);

            SDL_RenderPresent(renderer);
        }
    }

    SDL_DestroyRenderer(renderer);
    SDL_DestroyWindow(window);

    SDL_Quit();

    for (unsigned int i = 0; i < agents.size(); i++)
    {
        delete agents[i];
    }

    return 0;
}