Ok, i fixed it. I just replaced all the (*show).SetImage with (*show).Rotate.
The piece rotates but 1 second after i press the button. Maybe it is because of this part of the code here:
while (myClock.GetElapsedTime() <= Tetris.GetHeight())
{
while (Tetris.GetEvent(Termino))
{
if (Termino.Type == sf::Event::Closed)
Tetris.Close();
if ((Termino.Type == sf::Event::KeyPressed) && (Termino.Key.Code == sf::Key::Up))
(*show).Rotate(90);
if ((Termino.Type == sf::Event::KeyPressed) && (Termino.Key.Code == sf::Key::Escape))
Tetris.Close();
}
// This is the part I was talking about, I made it for the piece to move down 1 block per second.
Tetris.Clear();
(*show).Move(0, 10);
while (myClock.GetElapsedTime() < 1.f);
myClock.Reset();
Tetris.Draw(*show);
Tetris.Display();
}