Une implémentation du jeu de la vie en C avec la SDL

main.c

#include <stdio.h>
#include <stdbool.h>
#include <time.h>
#include <stdint.h>
#include <stdlib.h>

#include <SDL.h>

#define GRID_WIDTH 500
#define GRID_HEIGHT 500

#define ALIVE 0
#define DEAD 255

void applyConway (uint8_t * cells);
void applyRandom(uint8_t * cells);
void copyCellsToTexture(uint8_t * cells, SDL_Texture * gridTexture);

int main(int argc, char ** argv) {
  SDL_Window * window;
  SDL_Renderer * renderer;
  SDL_Texture * gridTexture;
  SDL_PixelFormatEnum format = SDL_PIXELFORMAT_RGB332;

  uint8_t cells[GRID_HEIGHT * GRID_WIDTH];

  SDL_Init(SDL_INIT_VIDEO);
  SDL_CreateWindowAndRenderer(1000, 1000, 0, &window, &renderer);
  SDL_SetWindowTitle(window, "Jeu de la vie");

  gridTexture = SDL_CreateTexture(renderer, format, SDL_TEXTUREACCESS_STREAMING, GRID_WIDTH, GRID_HEIGHT);

  applyRandom(cells);
  copyCellsToTexture(cells, gridTexture);

  SDL_RenderCopy(renderer, gridTexture, NULL, NULL);
  SDL_RenderPresent(renderer);

  while (true) {
    SDL_Event event;
    while (SDL_PollEvent(&event)) {
      if (event.type == SDL_QUIT) {
        SDL_DestroyWindow(window);
        SDL_DestroyRenderer(renderer);
        SDL_Quit();
        return EXIT_SUCCESS;
      }

      if (event.type == SDL_MOUSEBUTTONDOWN) {
        applyConway(cells);
        copyCellsToTexture(cells, gridTexture);

        SDL_RenderCopy(renderer, gridTexture, NULL, NULL);
        SDL_RenderPresent(renderer);
      }
    }
  }
  return EXIT_SUCCESS;
}

void applyConway (uint8_t * cells) {
  uint8_t * born[GRID_WIDTH*GRID_HEIGHT];
  uint8_t * dead[GRID_WIDTH*GRID_HEIGHT];
  int birthCount = 0, deathCount = 0;
  for (int y=0; y<GRID_HEIGHT; y++) for (int x=0; x<GRID_WIDTH; x++) {
    int neightboorsCount = 0;
    for (int yn = y-1; yn <= y+1; yn++) for (int xn = x-1; xn <= x+1; xn++) {
      if (x==xn && y==yn) continue;
      if (xn < 0 || xn >= GRID_WIDTH) continue;
      if (yn < 0 || yn >= GRID_HEIGHT) continue;
      neightboorsCount += cells[yn * GRID_WIDTH + xn] == ALIVE;
    }

    if (cells[y * GRID_WIDTH + x] == DEAD &&  neightboorsCount == 3) {
      born[birthCount] = cells + y * GRID_WIDTH + x;
      birthCount++;
    }
    if (cells[y * GRID_WIDTH + x] == ALIVE && (neightboorsCount < 2 || neightboorsCount > 3)) {
      dead[deathCount] = cells + y * GRID_WIDTH + x;
      deathCount++;
    }
  }

  for (int i = 0; i<deathCount; i++) *(dead[i]) = DEAD;
  for (int i = 0; i<birthCount; i++) *(born[i]) = ALIVE;
}

void applyRandom(uint8_t * cells) {
  srand(time(0));
  for (int y=0; y<GRID_HEIGHT; y++) for (int x=0; x<GRID_WIDTH; x++) {
    cells[y * GRID_WIDTH + x] = (random() % 2) ? ALIVE: DEAD;
  }
}

void copyCellsToTexture(uint8_t * cells, SDL_Texture * gridTexture) {
  uint8_t * pixels;
  int pitch;
  SDL_LockTexture(gridTexture, NULL, (void**)&pixels, &pitch);
    for (int y=0; y<GRID_HEIGHT; y++) for (int x=0; x<GRID_WIDTH; x++) {
      pixels[y * pitch + x] = cells[y * GRID_WIDTH + x];
    }
  SDL_UnlockTexture(gridTexture);
}

Makefile

main: main.c
	gcc -o $@ $^ `sdl2-config --cflags --libs`