function fromRotation$2(out, rad) {
    var s = Math.sin(rad),
        c = Math.cos(rad);
    out[0] = c;
    out[1] = s;
    out[2] = 0;
    out[3] = -s;
    out[4] = c;
    out[5] = 0;
    out[6] = 0;
    out[7] = 0;
    out[8] = 1;
    return out;
  }
Creates a matrix from a given angle
This is equivalent to (but much faster than):

    mat3.identity(dest);
    mat3.rotate(dest, dest, rad);

@param {mat3} out mat3 receiving operation result
@param {Number} rad the angle to rotate the matrix by
@returns {mat3} out