createStarNames関数

The names of the brightest stars for a sky of your own. It names only stars that have a name (the 335 of the IAU Working Group on Star Names that the catalogue holds), only those inside the view and not behind a body that covers them, never two names on each other, and never a name that runs off the view. count and magnitude limit it: with both, the stars must be bright enough and no more than count are shown. With neither it names nothing.

After the first call nothing is allocated by update, so a page may call it on every frame it moves. At rest there is nothing to call: the labels stay as they are.

import { createStarNames } from "@johnmorrisdotca/hoshi-stars/sky-labels";

function createStarNames(settings?: StarNamesSettings): StarNames

import { createStarNames, discCover } from "@johnmorrisdotca/hoshi-stars/sky-labels";

const names = createStarNames({ count: 6 });
const project = (ra: number, dec: number, out: { x: number; y: number }): boolean => {
  out.x = 640 - ra * 3 + 540;
  out.y = 360 - dec * 3;
  return true;
};
names.update(project, { width: 1280, height: 720 }, discCover(640, 900, 300));
console.log(names.labels.map((label) => label.text));

[ 'Sirius', 'Canopus', 'Arcturus', 'Vega', 'Capella', 'Rigel' ]