向它所面对的方向移动一个对象: java

Question

因此，我试图使一个小型测试游戏的基础引擎，是一个自上而下的射手。我大部分时间都在旋转，但我不能让它朝着它所面对的方向正确地移动。套餐游戏；

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.geom.AffineTransform;
import javax.swing.JFrame;
import javax.swing.JPanel;


public class Rotation extends JPanel implements KeyListener{
    private static double i = 0, inc = 0.1, iBase, speed = 0;
    private static int xPos = 0, yPos = 0, width = 100, height = 50;

    static boolean pressedA = false, pressedD = false, slowdown = false;
    public static void main(String[] args) throws InterruptedException {
        System.out.println(i);
        JFrame f = new JFrame();
        Rotation r = new Rotation();
        f.add(new Rotation());
        f.setSize(600, 600);
        f.setVisible(true);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.addKeyListener(r);


        while(true){
            move();
            accelerate();
            f.repaint();
            Thread.sleep(10);

        }

    }
public static void move(){
        xPos += speed * Math.cos(-1*Math.PI*i/180);
        yPos -= speed * Math.sin(-1*Math.PI*i/180);
        System.out.println(i);
    }

    public static void accelerate(){
        if(i>= 360)
            i=0;
        if(pressedA)
            i-=inc;

        if(pressedD)
            i+=inc;

        if(inc<2 && !slowdown && (pressedA || pressedD))
            inc+= 0.01;

        if(slowdown && inc>=0.02) {
            inc-=0.2;
            if(inc <= 0.02){
                slowdown = false;
                pressedA = false;
                pressedD = false;
            }
            if(pressedA)
                i-=inc;

            if(pressedD)
                i+=inc;
        }

        //i = Math.round10(i, -2);
        System.out.println(inc);
    }

    public void paint(Graphics g) {

        Graphics2D g2d = (Graphics2D) g.create();

        g2d.setPaint(new Color(150, 150, 150));
        g2d.fillRect(20, 20, 80, 50);
        g2d.translate(180, -50);
        g2d.rotate(Math.toRadians(i), xPos+width/2, yPos+height/2);


        g2d.fillRect(xPos, yPos, width, height);

        g2d.dispose();

        //System.out.println("repainted");
    }


    public void keyPressed(KeyEvent e) {
        int keyCode = e.getKeyCode();

        if (keyCode == KeyEvent.VK_W) {
            System.out.println("W is pressed");
            speed = 2;
            //slowdown = false;
        }
        if (keyCode == KeyEvent.VK_S) {
            System.out.println("S is pressed");
            speed = -2;
            //slowdown = false;
        }
        if (keyCode == KeyEvent.VK_A) {
            System.out.println("A is pressed");
            slowdown = false;


            pressedA = true;
        }
        if (keyCode == KeyEvent.VK_D) {
            System.out.println("D is pressed");


            slowdown = false;
            pressedD = true;
        }
        this.i=i;
        }

    @Override
    public void keyTyped(KeyEvent e) {
     }

    @Override
    public void keyReleased(KeyEvent e) {
        speed = 0;
        slowdown = true;

    }

-编辑-所以我认为这可能与旋转发生的地点有关。

Answer 1

sin和cos函数的角度值必须以弧度表示。做这样的事：

xPos += speed * Math.cos(-1*Math.PI*i/180);

这可能会解决你的问题