c++ - SFML 没有正确移动 Sprite

Question

SFML 不会将 Sprite 移动超过 1 个像素(即使保持)。它还会在松开按住的箭头键时将 Sprite 移回其设定位置。

void Engine::mainLoop() {
     //Loop until window is closed
     while (window->isOpen()) {
          processInput();
          update();
          sf::Sprite test;
          sf::Texture texTest;
          texTest.loadFromFile("img.png");
          test.setTexture(texTest);
          test.setPosition(50, 50);
          if (sf::Keyboard::isKeyPressed(sf::Keyboard::Key::Up))
               test.move(0, -1);
          if (sf::Keyboard::isKeyPressed(sf::Keyboard::Key::Down))
               test.move(0, 1);
          if (sf::Keyboard::isKeyPressed(sf::Keyboard::Key::Left))
               test.move(-1, 0);
          if (sf::Keyboard::isKeyPressed(sf::Keyboard::Key::Right))
               test.move(1, 0);
          window->clear(sf::Color::Black);
          window->draw(test);
          renderFrame();
          window->display();
     }
}

Answer 1

除了提到您始终设置位置的评论之外，您还在每一帧重新创建 Sprite ，因此即使您不调用 setPosition

，它的位置也将始终被重置

附带说明一下，您还在每一帧加载纹理，这是非常低效的!

这应该是你想要的:

void Engine::mainLoop() {
  sf::Sprite test;
  sf::Texture texTest;
  texTest.loadFromFile("img.png");
  test.setTexture(texTest);
  test.setPosition(50, 50);

 //Loop until window is closed
 while (window->isOpen()) {
      processInput();
      update();
      if (sf::Keyboard::isKeyPressed(sf::Keyboard::Key::Up))
           test.move(0, -1);
      if (sf::Keyboard::isKeyPressed(sf::Keyboard::Key::Down))
           test.move(0, 1);
      if (sf::Keyboard::isKeyPressed(sf::Keyboard::Key::Left))
           test.move(-1, 0);
      if (sf::Keyboard::isKeyPressed(sf::Keyboard::Key::Right))
           test.move(1, 0);
      window->clear(sf::Color::Black);
      window->draw(test);
      renderFrame();
      window->display();
 }
}