docs: public static DMatrix2x2 transpose( DMatrix2x2 input , DMatrix2x2 output ) {
          if( input == null )
              input = new DMatrix2x2();
  
          output.a11 = input.a11;
          output.a12 = input.a21;
          output.a21 = input.a12;
          output.a22 = input.a22;
  
          return output;
      }