simple.c

#include <assert.h> /* assert */
#include <stddef.h> /* ptrdiff_t */
#include <stdint.h> /* UINT64_C, etc */
#include <stdio.h> /* printf */
#include <stdlib.h> /* EXIT_FAILURE, etc */
#include <string.h> /* memset */

#define TPH_POISSON_IMPLEMENTATION
#include "thinks/tph_poisson.h"

static_assert(sizeof(tph_poisson_real) == sizeof(float), "");

int main(int argc, char *argv[])
{
  (void)argc;
  (void)argv;

  /* clang-format off */
  const tph_poisson_real bounds_min[2] = { 
    (tph_poisson_real)-10, (tph_poisson_real)-10 };
  const tph_poisson_real bounds_max[2] = { 
    (tph_poisson_real)10, (tph_poisson_real)10 };
  /* clang-format on */

  /* Configure arguments. */
  const tph_poisson_args args = { .bounds_min = bounds_min,
    .bounds_max = bounds_max,
    .radius = (tph_poisson_real)3,
    .ndims = INT32_C(2),
    .max_sample_attempts = UINT32_C(30),
    .seed = UINT64_C(1981) };

  /* Using default allocator (libc malloc). */
  const tph_poisson_allocator *alloc = NULL;

  /* Initialize empty sampling. */
  tph_poisson_sampling sampling;
  memset(&sampling, 0, sizeof(tph_poisson_sampling));

  /* Populate sampling with points. */
  const int ret = tph_poisson_create(&args, alloc, &sampling);
  if (ret != TPH_POISSON_SUCCESS) {
    /* No need to destroy sampling here! */
    printf("Failed creating Poisson sampling! Error code: %d\n", ret);
    return EXIT_FAILURE;
  }

  /* Retrieve sampling points. */
  const tph_poisson_real *samples = tph_poisson_get_samples(&sampling);
  if (samples == NULL) {
    /* Shouldn't happen since we check the return value from tph_poisson_create! */
    printf("Bad samples!\n");
    tph_poisson_destroy(&sampling);
    return EXIT_FAILURE;
  }

  /* Print first and last sample positions. */
  /* clang-format off */
  assert(sampling.nsamples >= 2);
  printf("\n%s:\n"
         "samples[%td] = ( %.3f, %.3f )\n"
         "...\n"
         "samples[%td] = ( %.3f, %.3f )\n\n", 
    "simple (C)",
    (ptrdiff_t)0, 
    (double)samples[0], 
    (double)samples[1],
    (ptrdiff_t)(sampling.nsamples - 1),
    (double)samples[(sampling.nsamples - 1) * sampling.ndims],
    (double)samples[(sampling.nsamples - 1) * sampling.ndims + 1]);
  /* clang-format on */

  /* Free memory. */
  tph_poisson_destroy(&sampling);

  return EXIT_SUCCESS;
}