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#include <stdint.h> // size_t
#include "util.h"
#include "km.h"

void
km_set_draw(
  const km_set_t * const set,
  uint8_t * const rgb,
  const size_t width,
  const size_t height,
  const uint32_t color
) {
  for (size_t i = 0; i < set->num_rows; i++) {
    const float *row = km_set_get_row(set, i);
    const size_t x = (width - 1) * row[0],
                 y = (height - 1) * row[1],
                 ofs = 3 * (width * y + x);

    if (x >= width || y >= height) {
      die(
        "km_set_draw(): point out of bounds (row: %zu, point: [%0.2f, %0.2f], pixel: %zux%zu, bounds: %zux%zu)",
        i, row[0], row[1], x, y, width, height
      );
    }
                
    rgb[ofs + 0] = (color & 0xff0000) >> 16;
    rgb[ofs + 1] = (color & 0x00ff00) >> 8;
    rgb[ofs + 2] = (color & 0x0000ff);
  }
}