code: func (g *GeoM) Element(i, j int) float64 {
  	switch {
  	case i == 0 && j == 0:
  		return float64(g.a_1) + 1
  	case i == 0 && j == 1:
  		return float64(g.b)
  	case i == 0 && j == 2:
  		return float64(g.tx)
  	case i == 1 && j == 0:
  		return float64(g.c)
  	case i == 1 && j == 1:
  		return float64(g.d_1) + 1
  	case i == 1 && j == 2:
  		return float64(g.ty)
  	default:
  		panic("ebiten: i or j is out of index")
  	}
  }
docs: // Element returns a value of a matrix at (i, j).