code: func (a Affine) TransformCenter(dst draw.Image, src image.Image, i interp.Interp) error {
  	if dst == nil {
  		return errors.New("graphics: dst is nil")
  	}
  	if src == nil {
  		return errors.New("graphics: src is nil")
  	}
  
  	return a.CenterFit(dst.Bounds(), src.Bounds()).Transform(dst, src, i)
  }
docs: // TransformCenter applies the affine transform to src and produces dst.
  // Equivalent to
  //   a.CenterFit(dst, src).Transform(dst, src, i).