Question

因此，对于我在Java课程中的最后一个，我们正在制作一个小行星游戏（除了官方版本的简单版本，因为时间不够）。

问题是当我们的船发射一个镜头（空格键）时我们添加（镜头，x，y），但是当我们再次点击空格键时它只需要拍摄并将其放回原始的x，y。所以现在我们只能在屏幕上一次开枪。我们希望能够发射多个镜头并让它们全部可见并且充实。

不知道如何做到这一点。欢迎任何帮助，谢谢。

P.S。如果需要，我将添加我们的代码。 P.S.S.很抱歉再次发布这个我以为我可以稍后编辑帖子，这就是为什么我没有包含代码但显然没有。

package week7Homework;
import acm.program.GraphicsProgram;
import java.util.*;
import java.awt.event.*;


import acm.graphics.*;
import java.awt.Color;
import java.awt.Image;

public class space8bit extends GraphicsProgram
{
    /* Initialize everything that is needed */
      final int WIN_HEIGHT = 800;
      final int WIN_WIDTH = 1900;
      GImage space = new GImage("/College/IT219/Week7/src/week7Homework/outerspace.png");
      GImage ship = new GImage("/College/IT219/Week7/src/week7Homework/ship.png");
      GImage explosion = new GImage("/College/IT219/Week7/src/week7Homework/explosion.png");
      GImage [] ast = new GImage[6];
      Random rand = new Random();
      pewpew shots = new pewpew();
      int shipx;
      int shipy;



public void init()
{
      setSize(WIN_WIDTH, WIN_HEIGHT);
      add(space);
      ship.setLocation(50,330);
      ship.scale(.8);
      add(ship);
      addKeyListeners( );

      //scale explosion
      explosion.scale(.5);

}
public void keyPressed(KeyEvent e)
{
int key = e.getKeyCode( );
if (key == KeyEvent.VK_UP)
{ ship.move(0, -15); }
/*else if (key == KeyEvent.VK_SPACE)
{ xMove = MV_AMT; }*/
else if (key == KeyEvent.VK_DOWN)
{ ship.move(0, 15); }
else if (key == KeyEvent.VK_SPACE)
{shipx =  (int)ship.getX()+195;
shipy = (int)ship.getY() + 80;
    add(shots,shipx,shipy);
}

}
public void asteriods()
{
    GImage ast1 = new GImage("/College/IT219/Week7/src/week7Homework/asteriod.png",1300,100);
    GImage ast2 = new GImage("/College/IT219/Week7/src/week7Homework/asteriod.png",1750,250);
    GImage ast3 = new GImage("/College/IT219/Week7/src/week7Homework/asteriod.png",1650,350);
    GImage ast4 = new GImage("/College/IT219/Week7/src/week7Homework/asteriod.png",1550,650);
    GImage ast5 = new GImage("/College/IT219/Week7/src/week7Homework/asteriod.png",1450,600);
    GImage ast6 = new GImage("/College/IT219/Week7/src/week7Homework/asteriod.png",1350,750);
    ast [0] =  ast1;
    ast [1] =  ast2;
    ast [2] =  ast3;
    ast [3] =  ast4;
    ast [4] =  ast5;
    ast [5] =  ast6;

    add(ast[0]);
    add(ast[1]);
    add(ast[2]);
    add(ast[3]);
    add(ast[4]);
    add(ast[5]);


}

public void run()
{
    asteriods();
    while(true)
    {
        pause(120);

        int random1x = rand.nextInt(-1+1+6)-9;
        int random2x = rand.nextInt(-1+1+6)-15;
        int random3x = rand.nextInt(-1+1+6)-25;
        int random4x = rand.nextInt(-1+1+6)-16;
        int random5x = rand.nextInt(-1+1+6)-8;
        int random6x = rand.nextInt(-1+1+6)-13;

        ast[0].move(random1x, 0);
        ast[1].move(random2x, 0);
        ast[2].move(random3x, 0);
        ast[3].move(random4x, 0);
        ast[4].move(random5x, 0);
        ast[5].move(random6x, 0);

        shots.move(50, 0);

        for (int i = 0; i < ast.length; i++)
        {
            //integer that gets bounds of all rectangles and ovals in the arrays. 
            GRectangle asteroidBounds = ast[i].getBounds();

            //check for collision with other objects
            if (shots.getBounds().intersects(asteroidBounds))
            {
                int shotX = (int)shots.getX();
                int shotY = (int)shots.getY();

                pause(10);
                remove(ast[i]);
                add(explosion, shotX-100, shotY - 50);
                remove(shots);
                pause(25);
                remove(explosion);


            }

            else if (ship.getY() <= 0)
            {
                ship.move(0, 15);
            }
            else if (ship.getY() >= WIN_HEIGHT - 168)
            {
                ship.move(0, -15);
            }
        }
    }
}

}

这里也是一个示例代码，更短，但做同样的事情。只需按空格键，您就会看到我在说什么。

package week7Homework;

import acm.graphics.*;
import acm.program.*;

import java.awt.*;
import java.awt.event.*;

public class collisionTry extends GraphicsProgram 
{

    final int WIN_WIDTH = 500;
    final int WIN_HEIGHT = 500;


    GOval ship = new GOval(100, 250, 50, 50);

    GImage bullet = new GImage("/College/IT219/Week7/src/week7Homework/bullet.gif", 50, 50);

    GImage bullet2;


    boolean bulletFired;


    public void init()
    {
        setSize(WIN_WIDTH, WIN_HEIGHT);

        addKeyListeners();

    }



    public void run()
    {
        GRect rect = new GRect(400, 200, 50, 150);


        add(rect);
        rect.setColor(Color.BLACK);
        rect.setFilled(true);

        add(ship);
        ship.setColor(Color.BLACK);
        ship.setFilled(true);

        while (true)
        {
            pause(50);
            rect.move(-1, 0);

            //bullet.move(5, 0);

            if (bulletFired == true)
            {
                bullet.move(5, 0);

            }

            if (bullet.getBounds().intersects(rect.getBounds()))
            {
                remove(rect);
                remove(bullet);
            }
        }

    }//run

    public void keyPressed(KeyEvent e)
    {
        int key = e.getKeyCode();
        if(key == KeyEvent.VK_SPACE)
        {

            int shipX = (int)ship.getX();
            int shipY = (int)ship.getY();
            add(bullet, shipX+50, shipY+25);
            bulletFired = true;

        }
        else if (key == KeyEvent.VK_UP){
            ship.move(0, -5);
        }
    }





}

Answer 1

这是因为你在整场比赛中只有1个子弹

if (bulletFired == true) {
    bullet.move(5, 0);
}

你告诉一个子弹回到（5,0）

每次按空格键时，您需要找到一种制作新子弹对象的方法：

if (key == KeyEvent.VK_SPACE) {
    int shipX = (int)ship.getX();
    int shipY = (int)ship.getY();

    Bullet firedBullet = new Bullet(/* params if any, x? y? */);

    add(firedBullet, shipX+50, shipY+25);
    bulletFired = true;
}

虽然这是我对自己如何做事的看法，但这可能不适用于你的游戏（我不知道你有什么课程，他们的角色等）。但希望你能看到我所得到的并适应它。

现在因为你有多个子弹，你还必须照顾他们的一生。你在游戏开始时发射了1000枚子弹，它们就会离开屏幕。你不想浪费时间在游戏的其他部分画出它们。因此，无论您使用什么列表/数组来跟踪要绘制的对象，您都必须定期查找并删除那些已经脱离屏幕的对象。

Java Asteroids游戏如何能够在没有第一次射击消失的情况下发射多次射击？

1 个答案: