基于easyx的c++贪吃蛇

本代码来自于easyx讨论群的分享

先上效果图，其实也只是画了简单的圈圈代表蛇和食物，背景就是黑色的。

#include "stdafx.h"
#include <iostream>
#include <stdlib.h>
#include <time.h>
#include <conio.h>
#include <graphics.h>

#define N 100

using namespace std;

enum moved { UP, DOWN, LEFT, RIGHT };
class Snake {
private:
	struct {      //整条蛇的信息
		int x;
		int y;
	}snake[100];
	struct {
		int life;   //为1代表还活着，为0代表已经死了
		int length; //代表蛇的长度，初始值为3
		enum moved direction;   //前进方向
	}snake_head;
	struct {       //食物的信息
		int x;
		int y;
	}food;
public:
	void display();    //显示界面
	void initSnake(); //随机生成蛇
	void move();//蛇移动
	void boundary_check();//边界判断
	void _food();//生成食物
	int food_eatcheck();//检查是否吃到食物,吃到则返回1，否则返回0
	int snake_eat();//判断贪吃蛇是否咬到自己，咬到则返回1，否则返回0
	void run();     //主要运行函数
};
void Snake::display() {
	initgraph(800, 600);
	setbkcolor(WHITE);   //设置背景颜色为白色
	cleardevice();       //将背景颜色刷新到窗口上
	setfillcolor(BLACK); //设置填充的颜色为黑色，之后话填充的图形都是这个颜色
	solidrectangle(20, 560, 560, 20);//这个区域每20*20为一个单位，一共有27*27个单位
}
//构造函数
void Snake::initSnake() {
	srand((unsigned)time(NULL));
	//因为一开始蛇是向右走的，所以不能让蛇初始化在太靠右边的地方
	int x = rand() % 22 + 3;  //范围是3-24
	int y = rand() % 22 + 3;  //加三是因为初始的长度是3，必须让整条蛇都在范围内
	this->snake[0].x = x * 20 + 10;//加十是因为要确定圆心的位置
	this->snake[0].y = y * 20 + 10;
	//默认蛇一开始是横着的所以三段的y坐标相同
	this->snake[1].y = this->snake[2].y = this->snake[0].y;
	this->snake[1].x = this->snake[0].x - 20;
	this->snake[2].x = this->snake[0].x - 40;
	setfillcolor(GREEN);   //设置填充色为绿色
	solidcircle(this->snake[0].x, this->snake[0].y, 10); //画圆
	solidcircle(this->snake[1].x, this->snake[1].y, 10);
	solidcircle(this->snake[2].x, this->snake[2].y, 10);
	this->snake_head.length = 3;
	this->snake_head.life = 1;
	this->snake_head.direction = RIGHT;
}
void Snake::move() {
	char ch;
	if (_kbhit()) {   //如果有输入的话就返回1，没有输入的话就返回0
		ch = _getch();//获取输入的字符
		switch (ch) {
			case 'w' :if (this->snake_head.direction != DOWN) this->snake_head.direction = UP; break;
			case 'W':if (this->snake_head.direction != DOWN) this->snake_head.direction = UP; break;
			case 's' :if (this->snake_head.direction != UP) this->snake_head.direction = DOWN; break;
			case 'S':if (this->snake_head.direction != UP) this->snake_head.direction = DOWN; break;
			case 'a':if (this->snake_head.direction != RIGHT) this->snake_head.direction = LEFT; break;
			case 'A':if (this->snake_head.direction != RIGHT) this->snake_head.direction = LEFT; break;
			case 'd':if (this->snake_head.direction != LEFT) this->snake_head.direction = RIGHT; break;
			case 'D':if (this->snake_head.direction != LEFT) this->snake_head.direction = RIGHT; break;
			default:break;
		}
	}
	//将蛇尾变成黑色
	int i = this->snake_head.length - 1;
	setfillcolor(BLACK);
	solidcircle(snake[i].x, snake[i].y, 10);
	//接下来遍历每个身体，每个身体都更新为前一个身体，蛇头除外
	for (; i > 0; i--) {
		this->snake[i].x = this->snake[i - 1].x;
		this->snake[i].y = this->snake[i - 1].y;
	}
	switch (this->snake_head.direction) {
		case RIGHT:this->snake[0].x += 20; break;
		case LEFT:this->snake[0].x -= 20; break;
		case UP:this->snake[0].y -= 20; break;
		case DOWN:this->snake[0].y += 20; break;
		default:break;
	}
	setfillcolor(GREEN);
	solidcircle(this->snake[0].x, this->snake[0].y, 10);//绘制蛇头
	Sleep(1000);
}
void Snake::boundary_check() {
	if (this->snake[0].x <= 30 || this->snake[0].x >= 550 || this->snake[0].y <= 30 || this->snake[0].y >= 550) {
		this->snake_head.life = 0; 
	}
}
void Snake::_food() {
	srand((unsigned)time(NULL));
	int x = rand() % 21 + 3;   //范围是3-23
	int y = rand() % 21 + 3;
	this->food.x = x * 20 + 10;
	this->food.y = y * 20 + 10;
	setfillcolor(YELLOW);
	solidcircle(this->food.x, this->food.y, 10);
}
int Snake::food_eatcheck() {
	if (this->snake[0].x == this->food.x && this->snake[0].y == this->food.y) {
		//如果满足条件就是吃到食物了
		this->snake_head.length++;//长度加一
		setfillcolor(GREEN);
		solidcircle(food.x, food.y, 10);
		int k = this->snake_head.length;
		//吃到食物之后最后要在尾巴处加一个长度
		switch (this->snake_head.direction) {
			case RIGHT:this->snake[k - 1].x = this->snake[k - 2].x - 20; this->snake[k - 1].y = this->snake[k - 2].y; break;
			case LEFT:this->snake[k - 1].x = this->snake[k - 2].x += 20; this->snake[k - 1].y = this->snake[k - 2].y; break;
			case UP:this->snake[k - 1].x = this->snake[k - 2].x; this->snake[k - 1].y = this->snake[k - 2].y + 20; break;
			case DOWN:this->snake[k - 1].x = this->snake[k - 2].x; this->snake[k - 1].y = this->snake[k - 2].y - 20; break;
			default:break;
		}
		setfillcolor(GREEN);
		solidcircle(this->snake[k - 1].x, this->snake[k - 1].y, 10);
		return 1;
	}
	return 0;
}
int Snake::snake_eat() {
	int i;
	for (i = 1; i < this->snake_head.length; i++) {
		if (this->snake[i].x == this->snake[0].x && this->snake[i].y == this->snake[0].y) {
			return 1;
		}
	}
	return 0;
}
void Snake::run() {
	display();  //显示游戏界面
	initSnake();
	_food();    //生成第一个食物
	while (true) {
		move();   //蛇移动
		if (snake_eat() == 1) {
			//自己吃到自己了，游戏失败
			cout << "自己吃到自己了，游戏失败" << endl;
			break;
		}
		boundary_check();//判断是否撞墙
		if (this->snake_head.life == 0) {
			//撞墙了
			cout << "撞墙了，游戏结束" << endl;
			break;
		}
		if (food_eatcheck() == 1) {
			_food();  //吃到食物就重新生成一个食物
		}
	}
}

int main() {
	Snake s;
	s.run();
	return 0;
}