用C语言写个最简单的贪吃蛇

Posted 2021-08-30 landaliming

一、思路

1. 定义二维数组window表示窗口；
2. 定义BLANK、BORDER、SNAKE、FOOD 分别表示：空白、边框、蛇身、食物；
3. 定义并初始化: 蛇头，蛇尾，食物；
4. 显示初始窗口；
5. 循环getchar，确定move方向，并使用fifo保存move方向，用于移动蛇尾；
6. 计算新的蛇头，判断新蛇头为空白则移动蛇尾；为食物则不移动蛇尾，并重新生成食物；其他情况则直接结束游戏；
7. 显示蛇头；
8. 显示窗口。

二、最终效果

lim@TIM:~/code/game$ ./main 
OOOOOOOOOOOOOOOO
O          *   O
O    DDD       O
O      D       O
O      D       O
O      D  D    O
O      DDDD    O
O              O
O              O
O              O
O              O
O              O
O              O
O              O
O              O
OOOOOOOOOOOOOOOO

三、代码

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <memory.h>

#define XLEN 16
#define YLEN 16

enum {
    BLANK = ' ',    // 空白
    BORDER = 'O',   // 边框
    SNAKE = 'D',    // 蛇身
    FOOD = '*',     // 食物
};

typedef struct point {
    int x;
    int y;
}point;

typedef struct queue
{
    char buf[256];
    char in;
    char out;
}queue;

void queue_init(queue *q)
{
    q->in = 0;
    q->out = 0;
}

void queue_push(queue *q, char c)
{
    q->buf[q->in++] = c;
}

char queue_pop(queue *q)
{
    return q->buf[q->out++];
}

static char window[XLEN][YLEN] = {0};
static point head;
static point tail;
static point food;
static queue action_queue;


point get_rand_point() {
    struct point node;
    do
    {
        node.x = rand() % (XLEN - 2) + 1;
        node.y = rand() % (YLEN - 2) + 1;
    } while (window[node.x][node.y] != BLANK);
    
    return node;
}

void window_init()
{
    memset(window, BLANK, sizeof(window));

    for (int x = 0; x < XLEN; ++x) {
        window[x][0] = BORDER;
        window[x][YLEN - 1] = BORDER;
    }

    for (int y = 0; y < YLEN; ++y) {
        window[0][y] = BORDER;
        window[XLEN - 1][y] = BORDER;
    }

    head = get_rand_point();
    tail = head;
    food = get_rand_point();
    window[head.x][head.y] = SNAKE;
    window[food.x][food.y] = FOOD;
}

void window_show()
{
    for (int y = 0; y < YLEN; ++y) {
        for (int x = 0; x < XLEN; ++x) {
            printf("%c", window[x][y]);
        }        
        printf("\\n");
    }    
}

int move(point *node, char c) 
{
    switch (c) {
    case 'a':
        node->x -= 1;
        break;
    case 'd':
        node->x += 1;
        break;
    case 'w':
        node->y -= 1;
        break;
    case 's':
        node->y += 1;
        break;

    default:
        return -1;
    }

    return 0; 
}

int main(int argc, char *argv[])
{
    srand((unsigned int)time(0));
    window_init();
    window_show(window, XLEN, YLEN);

    queue_init(&action_queue);
    char c = 0;
    while ((c = getchar()) != EOF) {
        if (move(&head, c))
            continue;  
        
        queue_push(&action_queue, c);

        switch (window[head.x][head.y]) {
        case BORDER:
        case SNAKE:
            goto gameover;
        case FOOD:
            food = get_rand_point();
            window[food.x][food.y] = FOOD;
            break;
         case BLANK:
            window[tail.x][tail.y]= BLANK;
            move(&tail, queue_pop(&action_queue));
            break;
        }
        
        window[head.x][head.y]= SNAKE;

        printf("\\r\\033[%dA", YLEN + 1);
        window_show((int **)window, XLEN, YLEN); 
    }

gameover:
    printf("game over\\n");
}