Function rotate

rotate(
    out: mat3.Mat3,
    a: readonly [
        number,
        number,
        number,
        number,
        number,
        number,
        number,
        number,
        number,
    ],
    rad: number,
): mat3.Mat3
Rotates a mat3 by the given angle
Parameters
- out: mat3.Mat3
  the receiving matrix
- a: readonly [
      number,
      number,
      number,
      number,
      number,
      number,
      number,
      number,
      number,
  ]
  the matrix to rotate
- rad: number
  the angle to rotate the matrix by
Returns mat3.Mat3
out
- Defined in core/mat3.ts:388