animation of sfml by using array of objects

问题

How to animate sprite with this code?I know what i should to add time delay,but how do it? I use array of objects to they's fast changing. or is it an irrational way of animating?

#include <SFML/Graphics.hpp>
#include <iostream>
using namespace std;
sf::RenderWindow window(sf::VideoMode(600, 400), "!!!");
void animation()
{
    sf::Texture arrayOfTexture[9];
    sf::Sprite imageOfLamp;
    arrayOfTexture[0].loadFromFile("1.png");
    arrayOfTexture[1].loadFromFile("2.png");
    arrayOfTexture[2].loadFromFile("3.png");
    arrayOfTexture[3].loadFromFile("4.png");
    arrayOfTexture[4].loadFromFile("5.png");
    arrayOfTexture[5].loadFromFile("6.png");
    arrayOfTexture[6].loadFromFile("7.png");
    arrayOfTexture[7].loadFromFile("8.png");
    arrayOfTexture[8].loadFromFile("9.png");
    for(;;)
    {
        for(int i= 0;i <=8;i++)
        {
            imageOfLamp.setTexture(arrayOfTexture[i]);
            window.draw(imageOfLamp);
        }
        for(int i =8;i >=0;i--)
        {
            imageOfLamp.setTexture(arrayOfTexture[i]);
            window.draw(imageOfLamp);
        }
    }
}

回答1:

As said in the comments. For the animation you need to capture the time. Or you will not be able to calculate the duration per frame. And you need to store the current frame in a variable. I put some comment in the example code below. It is not a class anymore because I think we need a running code block here.

An alternative is the sprite sheet, see https://www.gamefromscratch.com/post/2015/10/26/SFML-CPP-Tutorial-Spritesheets-and-Animation.aspx I can re-write the answer with the sprite sheet, but I think you wanted to understand the basic mechanism of an animation first. Please indicate so in a comment to my post.

Btw, if you are not used to game loops, have a look on https://gafferongames.com/post/fix_your_timestep/

#include <SFML/Graphics.hpp>

int main(){
  sf::RenderWindow renderWindow(sf::VideoMode(800, 600), "Color Animation");

  // Duration to control animation speed
  int currentFrame = 1;
  float duration = float();

  sf::Clock clock;
  sf::Event event;

  sf::Texture arrayOfTexture[9];
  arrayOfTexture[0].loadFromFile("1.png");
  arrayOfTexture[1].loadFromFile("2.png");
  arrayOfTexture[2].loadFromFile("3.png");
  arrayOfTexture[3].loadFromFile("4.png");
  arrayOfTexture[4].loadFromFile("5.png");
  arrayOfTexture[5].loadFromFile("6.png");
  arrayOfTexture[6].loadFromFile("7.png");
  arrayOfTexture[7].loadFromFile("8.png");
  arrayOfTexture[8].loadFromFile("9.png");

  // Assign basic texture to sprite
  sf::Sprite imageOfLamp;
  imageOfLamp.setTexture(arrayOfTexture[0]);

  while (renderWindow.isOpen()){
    // How much time since last loop?
    sf::Time dt = clock.restart();
    duration += dt.asSeconds();

    while (renderWindow.pollEvent(event)){
      //Handle events here
      if (event.type == sf::Event::EventType::Closed)
        renderWindow.close();
    }

    // Animation duration per frame (0.1f) reached
    if (duration > 0.1f){
      // Restart calculation of the duration
      duration = 0;

      // Loop through the animation frames
      if (currentFrame < 9){
        currentFrame += 1;
      } else {
        // Start from first frame if last frame reached
        currentFrame = 0;
      }
      imageOfLamp.setTexture(arrayOfTexture[currentFrame]);
    }

    // Clear render window and draw sprite
    renderWindow.clear(sf::Color::Black);
    renderWindow.draw(imageOfLamp);
    renderWindow.display();
  }
}

来源：https://stackoverflow.com/questions/52883445/animation-of-sfml-by-using-array-of-objects

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c++

sfml