func (f *Field) RotatePieceRight(piece *Piece, x, y int, angle Angle) Angle {
	if piece.collides(f, x, y, angle.RotateRight()) {
		return angle
	}
	return angle.RotateRight()
}
func (f *Field) RotatePieceRight(piece *Piece, x, y int, angle Angle) Angle {
	if piece.collides(f, x, y, angle.RotateRight()) {
		return angle
	}
	return angle.RotateRight()
}
// RotatePieceRight tries to rotate the piece to the right
// and returns the piece's next angle.