Windows SDL wrapper for https://github.com/harieamjari/raytracer

wmain_sdl.c

/* gcc wmain2.c tracer.c utils.c math.c -fopenmp -lm -lmingw32 -lSDL2main -lSDL2
 * -mwindows -Dmain=SDL_main -o wmain2 */
#include "common.h"
#include <SDL2/SDL.h>
#include <assert.h>
#include <process.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

typedef struct rgbai_t rgbai_t;
struct rgbai_t {
  uint8_t r, g, b, a;
};
rgbai_t **img_buf;

extern rgba_t get_pixel(int, int, uint64_t *);

int image_width, image_height;
scene3D scene = {0};
void putpixel(SDL_Surface *surface, int x, int y, uint8_t r, uint8_t g,
              uint8_t b) {
  /* Here p is the address to the pixel we want to set */
  uint32_t *p = (uint32_t *)surface->pixels + y * surface->w + x;
  *p = SDL_MapRGB(surface->format, r, g, b);
}

char render_finished = 0;
void render_scene(void *p) {
#pragma omp parallel for
  for (int y = 0; y < image_height; y++) {
    uint64_t rng = y;
    for (int x = 0; x < image_width; x++) {
      rgba_t rgba =
          get_pixel(x - (image_width / 2), (image_height / 2) - y, &rng);
      img_buf[y][x].r = (uint8_t)(rgba.r * 255.0);
      img_buf[y][x].g = (uint8_t)(rgba.g * 255.0);
      img_buf[y][x].b = (uint8_t)(rgba.b * 255.0);
      img_buf[y][x].a = (uint8_t)(rgba.a * 255.0);
    }
  }

  render_finished = 1;
}
int main(int argc, char *argv[]) {
  if (argc == 3) {
    image_width = atoi(argv[1]);
    image_height = atoi(argv[2]);
  } else {
    image_width = 640;
    image_height = 480;
  }
  // Initialize SDL
  if (SDL_Init(SDL_INIT_VIDEO) < 0) {
    fprintf(stderr,
            "SDL could not be initialized!\n"
            "SDL_Error: %s\n",
            SDL_GetError());
    return 0;
  }
  SDL_Window *window = NULL;
  SDL_Surface *surface = NULL;

  window = SDL_CreateWindow("Raytracer", SDL_WINDOWPOS_UNDEFINED,
                            SDL_WINDOWPOS_UNDEFINED, image_width, image_height,
                            SDL_WINDOW_SHOWN);

  if (window == NULL) {
    fprintf(stderr, "Window could not be created: %s\n", SDL_GetError());
    return 1;
  }
  surface = SDL_GetWindowSurface(window);
  SDL_Event event;

  img_buf = malloc(sizeof(rgbai_t *) * image_height);
  assert(img_buf != NULL);
  for (int y = 0; y < image_height; y++)
    img_buf[y] = calloc(sizeof(rgbai_t), image_width);
    // srand(time(NULL));

#include "scene.c"

  _beginthread(render_scene, 1024 * 1024 * 20, NULL);

  /* while render is not finished */
  while (!render_finished) {
    if (SDL_PollEvent(&event) && event.type == SDL_QUIT)
      break;
    //SDL_Delay(1500);
    //SDL_LockSurface(surface);
    for (int y = 0; y < image_height; y++)
      for (int x = 0; x < image_width; x++) {
        putpixel(surface, x, y, img_buf[y][x].r, img_buf[y][x].g,
                 img_buf[y][x].b);
      }

    //SDL_UnlockSurface(surface);
    SDL_UpdateWindowSurface(window);
  }
  for (int y = 0; y < image_height; y++)
    free(img_buf[y]);

  free(img_buf);

  while (1) {
    if (SDL_PollEvent(&event) && event.type == SDL_QUIT)
      break;
  }
  SDL_FreeSurface(surface);
  SDL_DestroyWindow(window);
  SDL_Quit();

  return 0;
}