setRotationZ method

void setRotationZ (double radians)

Turns the matrix into a rotation of radians around Z

Implementation 

void setRotationZ(double radians) {
  final double c = math.cos(radians);
  final double s = math.sin(radians);
  _m3storage[0] = c;
  _m3storage[1] = s;
  _m3storage[2] = 0.0;
  _m3storage[3] = -s;
  _m3storage[4] = c;
  _m3storage[5] = 0.0;
  _m3storage[6] = 0.0;
  _m3storage[7] = 0.0;
  _m3storage[8] = 1.0;
}