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const PRNG = require('./PRNG');
const badwords = require('./badwords');
const utils = require('./utils');
const Star = require('./Star');
const spiral_arms = 2;
const spiral_angle_degrees = 360;
const min_radius = 0.05;
const max_radius = 0.9;
const thickness = 0.1;
const scatter_theta = Math.PI / spiral_arms * 0.2;
const scatter_radius = min_radius * 0.4;
const spiral_b = spiral_angle_degrees / Math.PI * min_radius / max_radius;
const names = [];
const rejects = { badwords: 0, duplicates: 0 };
class Galaxy {
constructor(seed, number_of_stars) {
this.stars = [];
let i;
let position;
let pseudoRandom = new PRNG(seed);
for (i = 0; i < number_of_stars; i++) {
let number_of_syllables = Math.floor(pseudoRandom.value() * 2 + 2);
let new_name;
while (true) {
new_name = PRNG.random_name(pseudoRandom, number_of_syllables);
if (names.indexOf(new_name) >= 0) {
rejects.duplicates++;
}
else if (badwords.indexOf(new_name) >= 0 || badwords.indexContains(new_name) >= 0) {
rejects.badwords++
}
else {
break;
}
}
names.push(new_name);
let r = pseudoRandom.realRange(min_radius, max_radius);
let theta = spiral_b * Math.log(r / max_radius) + pseudoRandom.gaussrandom(scatter_theta);
r += pseudoRandom.gaussrandom(scatter_radius);
theta += pseudoRandom.range(0, spiral_arms - 1) * Math.PI * 2 / spiral_arms;
position = {
x: Math.cos(theta) * r,
y: Math.sin(theta) * r,
z: pseudoRandom.gaussrandom(thickness * 0.5)
};
this.stars.push(new Star(new_name, pseudoRandom.range(1, 100000), position));
}
}
}
module.exports = Galaxy;