// https://archive.org/details/HAKMEM/page/n73/mode/1up
// articles 149-152

#include <TVout.h>
TVout TV;

void setup() {
  TV.begin(PAL);
}

void loop() {
  for (int16_t radius = 40 << 8; radius > 16 << 8; radius -= 128) {
    int16_t x = radius, y = 0;
    for (uint16_t i = 900; --i; ) {
      x = x - (y >> 7);
      y = y + (x >> 7);
      TV.set_pixel(64 + (x >> 8), 48 + (y >> 8), 1);
    }
  }
}