Ideal sprite sheet size resolver

getSheetSize.js

export const getSheetSize = (spriteWidth, spriteHeight, spriteCount) => {
  const a = Math.max(spriteWidth, spriteHeight);
  const b = Math.min(spriteWidth, spriteHeight);
  let sizeA = 1 << (32 - Math.clz32(a));
  let sizeB = 1 << (32 - Math.clz32(b));
  let countA = 1;
  let countB = 1;

  while (spriteCount > countA * countB) {
    if (sizeA < sizeB) {
      sizeA <<= 1;
      countA = Math.floor(sizeA / a);
    } else {
      sizeB <<= 1;
      countB = Math.floor(sizeB / b);
    }
  }

  const bounds = [countA * a, Math.ceil(spriteCount / countA) * b];
  if (spriteWidth < spriteHeight) { bounds.reverse(); }
  const [width, height] = bounds;
  return { width, height };
}