section. y, err := new(field.Element).SetBytes(x) if err != nil { return nil, errors.New("edwards25519: invalid point encoding length") } // -x² + y² = 1 + dx²y² // x² + dx²y² = x²(dy² + 1) = y² - 1 // x² = (y² - 1) / (dy² + 1) // u = y² - 1 y2 := new(field.Element).Square(y) u := new(field.Element).Subtract(y2, feOne) // v = dy² + 1 vv := new(field.Element).Multiply(y2, d) vv = vv.Add(vv, feOne) // x = +√(u/v) xx, wasSquare := new(field.Element).SqrtRatio(u, vv) if wasSquare == 0 { return nil, errors.New("edwards25519:...

pkg image, method (Point) Sub(Point) Point
pkg image, method (Rectangle) Add(Point) Rectangle
pkg image, method (Rectangle) Canon() Rectangle
pkg image, method (Rectangle) Dx() int
pkg image, method (Rectangle) Dy() int
pkg image, method (Rectangle) Empty() bool
pkg image, method (Rectangle) Eq(Rectangle) bool
pkg image, method (Rectangle) In(Rectangle) bool
pkg image, method (Rectangle) Inset(int) Rectangle