如何延遲每發子彈？ （Java -Slick2d-游戲）

Question

（事件偵聽器在另一個類中）當Game.render = true時，我會得到源源不斷的子彈，這些子彈看起來更像激光束，我希望兩者之間存在間隙。 我的意思是，我希望生成子彈，就像從機槍發射子彈一樣。 我知道我應該添加一些時間，但是我不確定該怎么做才能獲得想要的效果。 任何幫助將不勝感激，因為我一直在努力使其工作約一個小時。

import java.util.ArrayList;
import org.newdawn.slick.GameContainer;
import org.newdawn.slick.Graphics;
import org.newdawn.slick.SlickException;

public class Bullet {

// ArrayList
@SuppressWarnings("unchecked")
static ArrayList<Bullet> arrL = new ArrayList();

public Bullet(int x , int y) throws SlickException{



}

public static void update(GameContainer gc, int u) throws SlickException{

// when the left mouse button is clicked Game.fire = true, the key listener is in   another class
    if(Game.fire){

        Bullet b = new Bullet(5,5);
        arrL.add(b);
        reloaded = false;

    }   if(!reloaded){



    }           
}

public static void renderBullets(GameContainer gc, Graphics g, int x, int y) {

         // draws a new bullet for every 'bullet object' in  the ArrayList called arrL
        for(Bullet b : arrL){

            g.drawRect(x,y,10,10);
            x++;

        }
    }
}

Answer 1

在這種情況下，我最常做的事情是添加一個時間變量，該變量會從每次更新中減去增量（您具有u的變量），直到其降至0以下，此時我將其重置：

// Set this to whatever feels right for the effect you're trying to achieve.
// A larger number will mean a longer delay.
private static int default_bullet_delay = 500;

private static int time = 0;

public static void update (GameContainer gc, int u) throws SlickException {
    time -= u;
    if (time <= 0 && Game.fire) {
        fireBullet();                 // Replace this with your code for firing the bullet
        time = default_bullet_delay;  // Reset the timer
    }

    // The rest of the update loop...
}

基本上，即使Game.fire是true，在計時器倒數之前，子彈也不會發射。 一旦發生這種情況，便會設置計時器，直到下一次計時器倒數，下一顆子彈才能發射。 如果將其設置為合理的較小值，則每個項目符號之間應存在一定的距離。

Answer 2

這就是我這樣做的方式：

boolean reloaded = false;  // Start with a reload becouse weapon not reload itself
float reloadTime = 100;     // This is the "timer" (the value doesnt matter)
float startReloadTime = 100; // This is the actual reload time

private void shoot(int delta, float screenWidth, float screenHeight) {

    // reload if not reloaded
    if (!reloaded) {
        reloadTime -= 0.5f * delta; // As I said, this is the timer

        // If the reload finished, set the timer back to the reload time
        if (reloadTime <= 0) {
            reloaded = true; // reloaded, we can shoot
            reloadTime = startReloadTime;
        }
    }

    // Shoot only if reloaded
    if (reloaded) {

        // This is some direction calculating, ignore for now
        float mouseWorldX = (x + (mouseX - screenWidth / 2));
        float mouseWorldY = (y + (mouseY - screenHeight / 2));

        float randomX = (float) Math.random() * (2000 / mouseWorldX);
        float randomY = (float) Math.random() * (2000 / mouseWorldY);

        mouseWorldX += randomX;
        mouseWorldY += randomY;

        // Add a new bullet element to the world (where will be rendered)
        world.add(new Shot(world, camera, x + width / 2, y + height / 2, mouseWorldX - 2.5f, mouseWorldY - 2.5f, 5, 5, new Color(1, 0, 0, 1f)));

        // We need to reload
        reloaded = false;
    }
}