code: public Matrix4d scaling(double x, double y, double z) {
          if ((properties & PROPERTY_IDENTITY) == 0)
              identity();
          m00 = x;
          m11 = y;
          m22 = z;
          boolean one = Math.abs(x) == 1.0 && Math.abs(y) == 1.0 && Math.abs(z) == 1.0;
          properties = PROPERTY_AFFINE | (one ? PROPERTY_ORTHONORMAL : 0);
          return this;
      }
docs: Set this matrix to be a simple scale matrix.
  
  @param x
  the scale in x
  @param y
  the scale in y
  @param z
  the scale in z
  @return this