asdf-games/lib/utilities/math.js

48 lines
720 B
JavaScript

function angle(a, b) {
const dx = a.x - b.x;
const dy = a.y - b.y;
const angle = Math.atan2(dy, dx);
return angle;
}
function clamp(x, min, max) {
return Math.max(min, Math.min(x, max));
}
function distance (a, b) {
const dx = a.x - b.x;
const dy = a.y - b.y;
return Math.sqrt(dx * dx + dy * dy);
}
function rand(min, max) {
return Math.floor(randf(min, max));
}
function randf(min, max) {
if (max == null) {
max = min || 1;
min = 0;
}
return Math.random() * (max - min) + min;
}
function randOneFrom(items) {
return items[rand(items.length)];
}
function randOneIn(max = 2) {
return rand(0, max) === 0;
}
module.exports = {
angle,
clamp,
distance,
rand,
randf,
randOneFrom,
randOneIn
};