Method set

src/utils/MStack.js:11–16

(m, i)

  }

  set(m, i) {
    if (i === 0) Mat3.set(m, this.mats[0]);
    else Mat3.multiply(this.mats[i - 1], m, this.mats[i]);

    this.size = Math.max(this.size, i + 1);
  }

  push(m) {
    if (this.size === 0) Mat3.set(m, this.mats[0]);