C++实现简单贪吃蛇游戏-编程知识

文章目录

- 1 开发历程
- 2 开发思路
- 3 使用介绍
- 4 源文件代码
- 5 游戏截图
- 6 小结

1 开发历程

游戏使用C++语言开发，是博主某个下午心血来潮的结果，后面又花了点时间加了计分，记录历史得分的功能。

2 开发思路

其实贪吃蛇主要难在蛇身的移动上，想像着蛇移动的模样，不禁让人想起链表这种数据结构，蛇的头带动蛇身的第二节，第二节带动第三节，每一节的移动方向会遗传给下一节，把握住这一点，难点就迎刃而解了。

3 使用介绍

由于整个项目只有一个文件，使用g++ -o snake main.cpp命令编译源文件，就可以得到一个名为snake的exe可运行程序，接着在exe同目录下打开cmd使用下面两个命令来执行程序：

snake start，开始游戏，w、s、a、d四个按键（不分大小写）控制蛇的移动方向，若蛇碰到墙壁或者自身，则游戏结束，并将计分存入名为rank.txt的文件中。
snake rank，查看历史前五得分记录。

4 源文件代码

#include <iostream>
#include <cstring>
#include <fstream>
#include <set>
#include <windows.h>
#include <conio.h>
#include <time.h>
#define HEIGHT 15
#define WIDTH 35
#define INIT_FLUSHRATE 200
#define INIT_SCORE 0
#define BODY '@'
#define EMPTY ' '
#define FOOD '*'
#define EDGE '#'
#define RANKFILE "rank.txt"
using namespace std;
bool keyIsput = false;enum class Orient {UP, DOWN, LEFT, RIGHT};typedef struct node {int row;int col;Orient direction;struct node* next;
} Node;typedef struct {int frow;int fcol;
} Food;bool FoodInSnake(const int& r, const int& c, Node* q) {while (q != NULL) {if (q->row == r && q->col == c)return true;q = q->next;}return false;
}void printRank(){ifstream fin(RANKFILE);if(!fin){cerr << RANKFILE << " does not exit or open file error!!";exit(1);}if(fin.peek()==ifstream::traits_type::eof()){cout << "file is empty";exit(1);}for(int i=0; i<5; ++i){int tmp;if(fin.eof())break;fin >> tmp;cout << "No." << i+1 << ": " << tmp << '\n';}
}class Snake {
private:Node* snakeHead;public:static Orient tmp_1, tmp_2;Snake(int r, int c, Orient ori) {snakeHead = new Node;snakeHead->row = r;snakeHead->col = c;snakeHead->direction = ori;snakeHead->next = NULL;}Node* getHead() {return snakeHead;}void setOrient(Orient ori) {tmp_1 = snakeHead->direction;snakeHead->direction = ori;}void move() {Node* p = snakeHead;while (p != NULL) {if (p == snakeHead) {if(keyIsput==false)tmp_1 = p->direction;}else if (p != snakeHead) {tmp_2 = p->direction;p->direction = tmp_1;tmp_1 = tmp_2;}switch (p->direction) {case Orient::UP:(p->row)--; break;case Orient::DOWN:(p->row)++; break;case Orient::LEFT:(p->col)--; break;case Orient::RIGHT:(p->col)++; break;default:break;}p = p->next;}keyIsput = false;}void longer(int row, int col, Orient direction) {Node* newbody = new Node;newbody->row = row;newbody->col = col;newbody->direction = direction;newbody->next = snakeHead;snakeHead = newbody;}virtual ~Snake() {Node *p = snakeHead, *q=NULL;while (p != NULL) {q = p->next;delete p;p = q;}}
};class Board {
private:Snake* s;int playground[HEIGHT][WIDTH] = {0};Food* food;bool foodIsEaten;bool gameOver;int score;int flushRate;public:Board(int sr=HEIGHT/2, int sc=WIDTH/2, Orient sori=Orient::RIGHT):gameOver(false),foodIsEaten(false),score(INIT_SCORE),flushRate(INIT_FLUSHRATE){s = new Snake(sr, sc, sori);playground[sr][sc] = 1;food = new Food;while ((food->frow = rand() % HEIGHT) == sr);while ((food->fcol = rand() % WIDTH) == sc);playground[food->frow][food->fcol] = 2;}void refresh() {s->move();Node* shead = s->getHead();if((gameOver = isCollision(shead)))return;if (shead->row == food->frow && shead->col == food->fcol) {foodIsEaten = true;switch (shead->direction){case Orient::UP: s->longer(shead->row - 1, shead->col, shead->direction); break;case Orient::DOWN: s->longer(shead->row + 1, shead->col, shead->direction); break;case Orient::LEFT: s->longer(shead->row, shead->col - 1, shead->direction); break;case Orient::RIGHT: s->longer(shead->row, shead->col + 1, shead->direction); break;default:break;}}if (foodIsEaten)refreshFood();memset(playground, 0, sizeof(playground));Node* p = s->getHead();while (p != NULL) {playground[p->row][p->col] = 1;p = p->next;}if(!foodIsEaten)playground[food->frow][food->fcol] = 2;}void printBoard() {for (int i = 0; i < HEIGHT; ++i) {for (int j = 0; j < WIDTH; ++j)playground[i][j] == 1 ? cout << BODY : (playground[i][j]==2? cout << FOOD:cout << EMPTY);i==0?cout << EDGE << "  Your score: " << score << '\n':cout << EDGE << '\n';}for (int k = 0; k < WIDTH; ++k)cout << EDGE;}void setSnakeOrient(Orient ori) {s->setOrient(ori);}void refreshFood() {score++;if(flushRate>50)flushRate-=5;Node* p = s->getHead();while (FoodInSnake(food->frow = rand() % HEIGHT, food->fcol = rand() % WIDTH, p));foodIsEaten = false;}void keyCheck() {if (_kbhit()) {keyIsput = true;char key = _getch();switch (key){case 'w':case'W':setSnakeOrient(Orient::UP); break;case 'a':case'A':setSnakeOrient(Orient::LEFT); break;case 's':case'S':setSnakeOrient(Orient::DOWN); break;case 'd':case'D':setSnakeOrient(Orient::RIGHT); break;default:break;}}}bool isCollision(Node*& head){if(head->row<0 || head->row>=HEIGHT)return true;if(head->col<0 || head->col>=WIDTH)return true;Node* p = head;while(p!=NULL){if(p!=head && p->row==head->row && p->col==head->col)return true;p = p->next;}return false;}int getFlushRate() const{return flushRate;}bool isGameOver(){return gameOver;}void printEnd(){ifstream fin(RANKFILE);if(!fin){fin.close();ofstream fout(RANKFILE);fout << score;fout.close();}else{set<int> r;int tmp;r.insert(score);while(!fin.eof()){fin >> tmp;r.insert(tmp);}fin.close();ofstream fout(RANKFILE);for(auto i=r.rbegin();i!=r.rend();++i)++i==r.rend()?fout << *(--i):fout << *(--i) << '\n';fout.close();}cout << "Game Over!!\n";cout << "Your score is " << score << ".\n";}~Board() {delete s;delete food;}
};Orient Snake::tmp_1 = Orient::RIGHT, Snake::tmp_2 = Orient::RIGHT;int main(int argc, char* argv[]) {if(argc!=2 || (strcmp(argv[1], "start")!=0 && strcmp(argv[1], "rank")!=0)){cerr << "Usage: \"snake start\" to begin game.\n";cerr << "       \"snake rank\" to look rank(1-5).";return 1;}if(strcmp(argv[1], "rank")==0){printRank();return 0;}srand((unsigned)time(NULL));Board* gameboard = new Board();while (!gameboard->isGameOver()) {gameboard->printBoard();Sleep(gameboard->getFlushRate());system("cls");gameboard->keyCheck();gameboard->refresh();}gameboard->printEnd();delete gameboard;return 0;
}