Chaos Game

Data de publicació: Mar 16, 2018 8:3:35 PM

#include <SDL2/SDL.h>

#include <math.h>

#define true     1

#define false    0

//Screen dimension in pixels

#define _W 800

#define _H 800

//Polygon type and radius dimension

#define N_POL 4

#define RADI ( _H / 2 )

//Predefined operation, divide by 2

#define DIV 2

//N_PLACES 0, Next vertex selected not the same vertex, 1: Not the next vertex in order, and so on ...

#define N_PLACES 2

//Cancel N_PLACES. ALL 1, all vertex possible selected

#define ALL 0

typedef struct punt{

    int x;

    int y;

} t_punt;

//Global pixel map

Uint32 pixels[_W * _H * sizeof(Uint32)];

void   _init_aleat();

int    _aleat(int n);

int    _aleat_diff(int n_pol, int vertex);

int    _nplaces_away_from_vertex(int vertex, int n_places, int n_pol);

int    _genera_poligon(t_punt POLIGON[], int n, int r);

int    _kaos( t_punt POLIGON[], t_punt *punt, int *vertex);

int main(int argc, char ** argv)

{

    int quit = false;

    SDL_Event event;

    t_punt POLIGON[N_POL], punt;

    int vertex;

    SDL_Init(SDL_INIT_VIDEO);

    SDL_Window * window = SDL_CreateWindow("SDL2 Chaos Game", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, _W, _H, 0);

    SDL_Renderer * renderer = SDL_CreateRenderer(window, -1, 0);

    SDL_Texture * texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STATIC, _W, _H);

    memset(pixels, 255, _W * _H * sizeof(Uint32));

    _init_aleat();

    punt.x = _aleat(_W);

    punt.y = _aleat(_H);

    _genera_poligon(POLIGON, N_POL, RADI);

    vertex = _aleat(N_POL);

    while (!quit)

    {

        SDL_UpdateTexture(texture, NULL, pixels, _W * sizeof(Uint32));

          if (( SDL_PollEvent(&event) ) && (event.type == SDL_QUIT )) quit = true;

          _kaos(POLIGON, &punt, &vertex);

          pixels[punt.y * _W + punt.x] = 1;

        SDL_RenderClear(renderer);

        SDL_RenderCopy(renderer, texture, NULL, NULL);

        SDL_RenderPresent(renderer);

    }

    SDL_DestroyTexture(texture);

    SDL_DestroyRenderer(renderer);

    SDL_DestroyWindow(window);

    SDL_Quit();

    return 0;

}

int _kaos( t_punt POLIGON[], t_punt *punt, int *vertex){

   switch ( ALL ){

        case 1:     *vertex = _aleat( N_POL );

                    break;

        case 0:    *vertex = _aleat_diff(N_POL, _nplaces_away_from_vertex(*vertex, N_PLACES, N_POL));

                    break;

        default:    break;

    }

    punt->x = punt->x + (POLIGON[*vertex].x - punt->x) / DIV;

    punt->y = punt->y + (POLIGON[*vertex].y - punt->y) / DIV;

}

void   _init_aleat(){srand(time(NULL));}

int    _aleat(int n){return rand() % n;}

int    _aleat_diff(int n_pol, int vertex){

        int v;

        v = _aleat(n_pol);

        while ( v == vertex ) v = _aleat(N_POL);

        return v;

}

int _nplaces_away_from_vertex(int vertex, int n_places, int n_pol){return ( (vertex + n_places) % n_pol );}

int _genera_poligon(t_punt POLIGON[], int n, int r){

int i;

for (i = 0; i < n; i++) {

    POLIGON[i].x = (int)(r - r * sinf(2 * M_PI * i / n));

    POLIGON[i].y = (int)(r - r * cosf(2 * M_PI * i / n));

}

}

gcc kaos.c -lm -lSDL2 -lSDL2main -o kaos

https://wiki.libsdl.org/APIByCategory