Java2D Platformer敌人运动

Question

嗯，具体而言我确实让敌人的运动正确，但我想实施一种让敌人不会从悬崖上掉下来的方式。 我尝试了几件事，但它只是不起作用： 以下是我发现与问题相关的代码：

实体超级班：

 package com.cutthedamntree.main.entity;

import java.awt.Graphics;
import java.awt.Rectangle;

import com.cutthedamntree.main.Id;
import com.cutthedamntree.main.handlers.Handler;

public abstract class Entity {

    protected int x, y, width, height, velX, velY;
    protected boolean solid;
    protected Id id;
    protected Handler handler;

    public boolean jumping = false;
    public boolean falling = true;
    public double gravity = 0.0;

    public int direction = 0; // 0 is right , 1 is left

    public Entity(int x, int y, int width, int height, boolean solid, Id id, Handler handler){
        this.x = x;
        this.y = y;
        this.width = width;
        this.height = height;
        this.solid = solid;
        this.id = id;
        this.handler = handler;
    }

    public abstract void render(Graphics g);
    public abstract void tick();

    public void die(){
            handler.removeEntity(this);
    }

    public int getX() {
        return x;
    }

    public void setX(int x) {
        this.x = x;
    }

    public int getY() {
        return y;
    }

    public void setY(int y) {
        this.y = y;
    }

    public int getWidth() {
        return width;
    }

    public void setWidth(int width) {
        this.width = width;
    }

    public int getHeight() {
        return height;
    }

    public void setHeight(int height) {
        this.height = height;
    }

    public int getVelX() {
        return velX;
    }

    public void setVelX(int velX) {
        this.velX = velX;
    }

    public int getVelY() {
        return velY;
    }

    public void setVelY(int velY) {
        this.velY = velY;
    }

    public boolean isSolid() {
        return solid;
    }

    public void setSolid(boolean solid) {
        this.solid = solid;
    }

    public Id getId() {
        return id;
    }

    public void setId(Id id) {
        this.id = id;
    }
    public Rectangle getBounds(){
        return new Rectangle(getX(), getY(), width, height);
    }

    public Rectangle getBoundsLeft() {
        return new Rectangle(getX(), getY()+3, 3, height-6);
    }

    public Rectangle getBoundsRight() {
        return new Rectangle(getX()+width-3, getY()+3, 3, height-6);
    }

    public Rectangle getBoundsTop() {
        return new Rectangle(getX()+3, getY(), width-6, 3);
    }

    public Rectangle getBoundsBottom() {
        return new Rectangle(getX()+3, getY()+height-3, width-6, 3);
    }
}

敌人类：

public class SimpleEnemy extends Entity {

    private Random r = new Random();

    public SimpleEnemy(int x, int y, int width, int height, boolean solid, Id id, Handler handler) {
        super(x, y, width, height, solid, id, handler);
        int random = r.nextInt((int)1);
        if(random == 0){
            velX = 3;
        }else if(random == 1){
            velX = -3;
        }

    }

    @Override
    public void render(Graphics g) {
        g.drawImage(Game.simplenemy.getBufferedImage(), x, y, width, height, null);

    }

    @Override
    public void tick() {
        x+=velX;
        y+=velY;

        for(int i=0;i<handler.tile.size();i++) {
            Tile t = handler.tile.get(i);
            if(t.isSolid()) {
                if(getBoundsTop().intersects(t.getBounds())) {
                    setVelY(0);

                }
                if(getBoundsBottom().intersects(t.getBounds()) == false && velX  > 0){
                    System.out.println("RIGHT");
                }if(getBoundsBottom().intersects(t.getBounds()) == false && velX < 0){
                    System.out.println("LEFT");
                }
                else{
                    setVelY(0);
                    if(falling) falling = false;
                    y = t.getY() - getHeight();
                    System.out.println("SOMETHNI");
                } 
                if(getBoundsLeft().intersects(t.getBounds())) 
                    velX *= -1;

                if(getBoundsRight().intersects(t.getBounds()))
                    velX *= -1;
            }
        }


        if(jumping){
            gravity-=0.4;
            setVelY((int)-gravity);
            if(gravity <= 0.5){
                jumping = false;
                falling = true;
            }
        }
            if(falling) {
                gravity += 0.4;
                setVelY((int)gravity);
    }

    }

    }

编辑： 处理程序类我称之为简单类：

int w = image.getWidth();
        int h = image.getHeight();
        for(int x = 0; x < w;x++ ){
            for(int y = 0; y < h;y++){
                int pixel = image.getRGB(x, y);
                int red = (pixel >> 16)& 0xff;
                int green = (pixel >> 8)& 0xff;
                int blue = (pixel)& 0xff;

                if(red==0&&green==0&&blue==0)addTile(new Wall(x * 64, y * 64, 64, 64, true, Id.Wall, this));
                if(red==0&&green==0&&blue==255)addEntity(new Player(x * 64, y * 64, 64, 64, true, Id.Player, this));
                if(red==255&&green==0&&blue==0)addEntity(new Mushroom(x*64, y*64, 64, 64, true, Id.Mushroom, this));
                if(red==100&&green==100&&blue==0)addEntity(new SimpleEnemy(x*64,y*64,64,64,true,Id.SimpleEnemy,this));
            }
        }