random walk ant

#include <iostream>
#include <SDL2/SDL.h>
#include <stdlib.h>
#include <time.h>



int energy = 16;
const int UPDATE_RATE = 0;
const int SCREEN_WIDTH = 1024;
const int SCREEN_HEIGHT = 1024;
const int GRID_SIZE = 4;  // Size of each grid cell
const int GRID_ROWS = SCREEN_HEIGHT / GRID_SIZE;
const int GRID_COLS = SCREEN_WIDTH / GRID_SIZE;

int antPos[2] = {GRID_ROWS/2,GRID_COLS/2};
int antCol[3] = {64,64,255};
int gridCell[GRID_ROWS][GRID_COLS];

int antDir=0;

void renderWholeGrid(SDL_Renderer* renderer) {
    // Clear the renderer
    SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);

    // Set a different color for each cell
    for (int i = 0; i < GRID_ROWS; ++i) {
        for (int j = 0; j < GRID_COLS; ++j) {
            int red   = gridCell[i][j]*32;
            int green = gridCell[i][j]*32;
            int blue  = gridCell[i][j]*32;

            SDL_SetRenderDrawColor(renderer, red, green, blue, 255);

            SDL_Rect cell = {j * GRID_SIZE, i * GRID_SIZE, GRID_SIZE, GRID_SIZE};
            SDL_RenderFillRect(renderer, &cell);
        }
    }

    SDL_SetRenderDrawColor(renderer, antCol[0], antCol[1], antCol[2], 255);


    SDL_Rect antCell = {antPos[0] * GRID_SIZE, antPos[1] * GRID_SIZE, GRID_SIZE, GRID_SIZE};
    SDL_RenderFillRect(renderer, &antCell);

    // Present the renderer
    SDL_RenderPresent(renderer);
}

void updateAnt(SDL_Renderer* renderer){


    //draw ant old position
        int red   = gridCell[antPos[1]][antPos[0]]*32;
        int green = gridCell[antPos[1]][antPos[0]]*32;
        int blue  = gridCell[antPos[1]][antPos[0]]*32;

        SDL_SetRenderDrawColor(renderer, red, green, blue, 255);

        SDL_Rect cell = {antPos[0] * GRID_SIZE, antPos[1] * GRID_SIZE, GRID_SIZE, GRID_SIZE};
        SDL_RenderFillRect(renderer, &cell);

    //move ant
        if(gridCell[antPos[1]][antPos[0]]){
            antDir+=1;
        }else{
            antDir-=1;
        }
        antDir=(antDir+4)%4;

        int deltay[] = {0,1,0,-1};
        int deltax[] = {-1,0,1,0};

        antPos[0]+=deltax[antDir];
        antPos[1]+=deltay[antDir];

        antPos[0] = (antPos[0] + GRID_ROWS) % GRID_ROWS;
        antPos[1] = (antPos[1] + GRID_COLS) % GRID_COLS;

    //update cell
        gridCell[antPos[1]][antPos[0]]=!gridCell[antPos[1]][antPos[0]];


    //draw ant
        SDL_SetRenderDrawColor(renderer, antCol[0], antCol[1], antCol[2], 255);
        SDL_Rect antCell = {antPos[0] * GRID_SIZE, antPos[1] * GRID_SIZE, GRID_SIZE, GRID_SIZE};
        SDL_RenderFillRect(renderer, &antCell);

    // Present the renderer
        SDL_RenderPresent(renderer);

    printf("x: %d ",antPos[0]);
    printf("y: %d   ",antPos[1]);
    printf("%d\n",gridCell[antPos[0]][antPos[1]]);
}


int main() {
    srand(time(NULL));

    for (int i = 0; i < GRID_ROWS; ++i) {
        for (int j = 0; j < GRID_COLS; ++j) {
            gridCell[i][j] = ((i+4) / 8 + (j+3) / 8) % 2;
        }
    }


    // Initialize SDL
    if (SDL_Init(SDL_INIT_VIDEO) < 0) {
        std::cerr << "SDL could not initialize! SDL_Error: " << SDL_GetError() << std::endl;
        return 1;
    }

    // Create a window
    SDL_Window* window = SDL_CreateWindow("Grid Renderer", 3400, 600, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN);
    if (window == nullptr) {
        std::cerr << "Window could not be created! SDL_Error: " << SDL_GetError() << std::endl;
        return 2;
    }

    // Create a renderer for the window
    SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
    if (renderer == nullptr) {
        std::cerr << "Renderer could not be created! SDL_Error: " << SDL_GetError() << std::endl;
        return 3;
    }

    bool quit = false;
    SDL_Event e;

    renderWholeGrid(renderer);

    Uint32 startTime = SDL_GetTicks();
    startTime+=UPDATE_RATE;
    int updateWholeRate=1000; //update whole screen per x frames
    int frameNum=0;

    while (!quit) {
        frameNum++;
        if(frameNum>updateWholeRate){
            frameNum=0;
            renderWholeGrid(renderer);
        }

        while (SDL_PollEvent(&e) != 0) {
            if (e.type == SDL_QUIT) {
                quit = true;
            }
            if (e.type == SDL_KEYDOWN && e.key.keysym.sym == SDLK_ESCAPE) {
                quit = true;
            }
        }

        // Calculate the time to render a frame
        Uint32 frameTime = SDL_GetTicks() - startTime;

        // Wait for the remainder of the 1-second frame
        if (frameTime < UPDATE_RATE) {
            SDL_Delay(UPDATE_RATE - frameTime);
        }

        startTime = SDL_GetTicks();

        updateAnt(renderer);
    }

    // Clean up and exit
    SDL_DestroyRenderer(renderer);
    SDL_DestroyWindow(window);
    SDL_Quit();

    return 0;
}