贪吃蛇|双人贪吃蛇游戏设计
1.设计物体结构
蛇结构:
struct SnakePlayer
{
int size;
int r;
int dir;
int speed;
POINT pos[SNAKE_SIZE];
bool live;
int score;
}snake;
食物结构:
struct Food
{
int x;
int y;
int r;
bool flag;
DWORD color;
}food,foodtest[FOOD_SIZE];
2.游戏初始化
void GameInit()
{
//播放背景音乐
mciSendString(_T("open ./res/Snake_BGM.mp3 alias BGM"), 0, 0, 0);
mciSendString(_T("play BGM repeat"), 0, 0, 0);
//创建一个窗口,控制窗口台是自动创建的,图形窗口是需要自己手动创建的(后加 SHOWCONSOLE)
initgraph(WIN_WIDTH, WIN_HEIGHT);
//加载开始界面
loadimage(&bg, _T("./res/Snake_Background.jpg"));
putimage(0, 0, &bg);
//让随机数每次进入时都不同,只调用一次!!!
srand(GetTickCount());
//开始界面
setbkmode(TRANSPARENT);//设置透明背景
settextcolor(GREEN);
settextstyle(60, 0, _T("黑体"));
outtextxy(WIDTH / 2, HEIGHT / 2 - 70,_T("贪吃蛇" ));
settextstyle(20, 0, _T("黑体"));
outtextxy(WIDTH / 2 + 30, HEIGHT / 2 + 20, _T("按'C'开始游戏" ));
while (!GetAsyncKeyState('C'));
//蛇初始状态
snake.size = SIZE_BEGIN;
snake.r = R_BEGIN;
snake.dir = RIGHT;
snake.speed=SPEED_MIN;
snake.live = true;
snake.score = 0;
for (int i = 0; i < snake.size; i++)
{
snake.pos[i].x = X_BEGIN - 10 * i;
snake.pos[i].y = Y_BEGIN;
}
//产生食物
ProduceFood();
}
3.游戏界面加载
void GameDraw()
{
BeginBatchDraw();
setbkcolor(RGB(28, 115, 119));
cleardevice();//是用当前背景色清空屏幕,并将当前点移至 (0, 0),EASYX自带
//游戏外界面
settextcolor(GREEN);
settextstyle(50, 0, _T("黑体"));
outtextxy(WIDTH + 10, 20, _T("贪吃蛇" ));
settextstyle(20, 0, _T("黑体"));
outtextxy(WIDTH + 10, 120, _T("开始/继续游戏——C"));
outtextxy(WIDTH + 10, 150, _T("重新开始——M"));
outtextxy(WIDTH + 10, 180, _T("暂停游戏——空格"));
outtextxy(WIDTH + 10, 210,_T("上——W或↑"));
outtextxy(WIDTH + 10, 240,_T("下——S或↓"));
outtextxy(WIDTH + 10, 270, _T("左——A或←"));
outtextxy(WIDTH + 10, 300,_T("右——D或→"));
outtextxy(WIDTH + 10, 330, _T("加速——B"));
//line(0, HEIGHT, WIDTH, HEIGHT);//画直线
rectangle(0, 0, WIDTH, HEIGHT);//画矩形边框
settextcolor(BLACK);
settextstyle(20, 0, _T("黑体"));
outtextxy(10, HEIGHT + 5,_T("当前分数:"));
char t[SNAKE_SIZE];
sprintf_s(t, "%d", snake.score);
outtextxy(140, HEIGHT + 5, *t);
for (int i = 0; i < snake.size; i++)
{
setfillcolor(RED);
solidcircle(snake.pos[i].x, snake.pos[i].y, snake.r);
}
if (food.flag)
{
setfillcolor(food.color);
solidcircle(food.x, food.y, food.r);
}
/*//测试用
for (int j = 0; j < FOOD_SIZE; j++)
{
if (foodtest[j].flag)
{
setfillcolor(foodtest[j].color);
solidcircle(foodtest[j].x, foodtest[j].y, foodtest[j].r);
}
}*/
EndBatchDraw();
}
4.随机生成一个食物
void ProduceFood()
{
food.r = rand() % 3 + 7;
//随机生成食物位置,不能在蛇的身体上
food.x = rand() % (WIDTH - 30) + food.r;
food.y = rand() % (HEIGHT - 30) + food.r;
while(1)
{
int i = 0;
for(; i < snake.size; i++)
{
if (snake.pos[i].x + snake.r >= food.x - food.r && snake.pos[i].x - snake.r <= food.x + food.r
&& snake.pos[i].y + snake.r >= food.y - food.r && snake.pos[i].y - snake.r <= food.y + food.r)
{
food.x = rand() % (WIDTH - 30) + food.r;
food.y = rand() % (HEIGHT - 30) + food.r;
break;
}
}
if (i == snake.size)
break;
}
//随机生成食物颜色,不能与背景相同
food.color = RGB(rand() % 256, rand() % 256, rand() % 256);
while (food.color == RGB(28, 115, 119))
{
food.color = RGB(rand() % 256, rand() % 256, rand() % 256);
}
food.flag = true;
}
5.蛇吃食物机制
void EatFood()
{
if (food.flag && snake.pos[0].x+snake.r > food.x - food.r && snake.pos[0].x - snake.r < food.x + food.r
&& snake.pos[0].y + snake.r > food.y - food.r && snake.pos[0].y - snake.r < food.y + food.r)
{
food.flag = false;
snake.size++;
snake.score++;
}
if (!food.flag)
{
ProduceFood();
}
}
6.控制蛇移动
蛇移动机制:
void SnakeMove()
{
//蛇的身体移动
for (int i = snake.size - 1; i > 0; i--)
{
//Sleep(1);
snake.pos[i] = snake.pos[i - 1];
}
//碰墙死亡机制
switch (snake.dir)
{
case UP:
snake.pos[0].y -= snake.speed;
break;
case DOWN:
snake.pos[0].y += snake.speed;
break;
case LEFT:
snake.pos[0].x -= snake.speed;
break;
case RIGHT:
snake.pos[0].x += snake.speed;
break;
}
//穿墙所需机制
/*
switch (snake.dir)
{
case UP:
snake.pos[0].y -= speed;
if (snake.pos[0].y < 0)
{
snake.pos[0].y = HEIGHT;
}
break;
case DOWN:
snake.pos[0].y += speed;
if (snake.pos[0].y > HEIGHT)
{
snake.pos[0].y = 0;
}
break;
case LEFT:
snake.pos[0].x -= speed;
if (snake.pos[0].x < 0)
{
snake.pos[0].x = WIDTH;
}
break;
case RIGHT:
snake.pos[0].x += speed;
if (snake.pos[0].x > WIDTH)
{
snake.pos[0].x = 0;
}
break;
}*/
}
按键控制:
void KeyCtrl()
{
//Windows函数, 非阻塞
//按键大写可检测到大小写,小写都检测不到
//按键需要顺序+else if,这样目前检测连续按不能往回走
if (GetAsyncKeyState(VK_UP) || GetAsyncKeyState('W'))
{
if (snake.dir != DOWN)
{
snake.dir = UP;
}
}
else if (GetAsyncKeyState(VK_LEFT) || GetAsyncKeyState('A'))
{
if (snake.dir != RIGHT)
{
snake.dir = LEFT;
}
}
else if (GetAsyncKeyState(VK_DOWN) || GetAsyncKeyState('S'))
{
if (snake.dir != UP)
{
snake.dir = DOWN;
}
}
else if (GetAsyncKeyState(VK_RIGHT) || GetAsyncKeyState('D'))
{
if (snake.dir != LEFT)
{
snake.dir = RIGHT;
}
}
if (GetAsyncKeyState('B'))
{
snake.speed += SPEED_GAP;
if (snake.speed>= SPEED_MAX)
{
snake.speed = SPEED_MIN;
}
}
if (GetAsyncKeyState(VK_SPACE))
{
while (!GetAsyncKeyState('C'));
}
}
7.蛇碰撞死亡机制
bool Bump()
{
//碰身体死亡
for (int i = 4; i < snake.size; i++) //最小情况为4
{
if (snake.pos[0].x == snake.pos[i].x && snake.pos[0].y == snake.pos[i].y)
{
//snake.live = false;
return false;
}
}
//碰墙死亡
if (snake.dir == LEFT && snake.pos[0].x - snake.r<0 || snake.dir == RIGHT && snake.pos[0].x + snake.r>WIDTH
|| snake.dir == UP && snake.pos[0].y - snake.r<0 || snake.dir == DOWN && snake.pos[0].y + snake.r>HEIGHT)
{
//snake.live = false;
return false;
}
return true; // 默认true,可不写
}
8.执行
int main()
{
while (1)
{
GameInit();
while (1)
{
//Producefoodtest();
GameDraw();
EatFood();
KeyCtrl();
SnakeMove();
FlushBatchDraw();
Sleep(100); //可以让速度更慢
if (!Bump() || GetAsyncKeyState('M'))
break;
}
//播放死亡时的背景音乐
mciSendString(_T("close BGM"), 0, 0, 0);
mciSendString(_T("open ./res/Snake_Dead.mp3"), 0, 0, 0);
mciSendString(_T("play ./res/Snake_Dead.mp3"), 0, 0, 0);
settextcolor(RED);
settextstyle(40, 0, _T("黑体"));
outtextxy(WIDTH + 7, 400, _T("GAME OVER!"));
settextstyle(20, 0, _T("黑体"));
outtextxy(WIDTH + 10, 450, _T("获得总分:"));
settextstyle(30, 0, _T("黑体"));
char t[SNAKE_SIZE];
sprintf_s(t, "%d", snake.score);
outtextxy(WIDTH + 140, 445, *t);
while (!GetAsyncKeyState('M'));
//停住播放。不能和play相邻,它会立即关闭,因为程序执行太快!
mciSendString(_T("close ./res/Snake_Dead.mp3"), 0, 0, 0);
}
return 0;
}
结果演示视频:
可见,我还对游戏画面进行了优化,添加了文字描述,画面较为美观。
基于此设计,我们可以衍生出双人贪吃蛇的游戏设计,这只不过是在贪吃蛇设计上添加一个蛇,再修改一下碰撞机制,比如说双方碰撞检测:
for (int k = 1; k < snake[i].size; k++)
{
if (i + 1 < SNAKE_NUM&&snake[i].live && snake[i+1].live)
{
if (snake[i].pos[0].x - snake[i].r < snake[i + 1].pos[k].x + snake[i].r && snake[i].pos[0].x + snake[i].r > snake[i + 1].pos[k].x - snake[i].r
&& snake[i].pos[0].y - snake[i].r < snake[i + 1].pos[k].y + snake[i].r && snake[i].pos[0].y + snake[i].r > snake[i + 1].pos[k].y - snake[i].r)
{
snake[i].live = false;
DeadFood(i);
}
}
if ((i - 1) >= 0&&snake[i].live && snake[i - 1].live)
{
if (snake[i].pos[0].x - snake[i].r < snake[i - 1].pos[k].x + snake[i].r && snake[i].pos[0].x + snake[i].r > snake[i - 1].pos[k].x - snake[i].r
&& snake[i].pos[0].y - snake[i].r < snake[i - 1].pos[k].y + snake[i].r && snake[i].pos[0].y + snake[i].r > snake[i - 1].pos[k].y - snake[i].r)
{
snake[i].live = false;
DeadFood(i);
}
}
}
还可以添加一些玩法,增加游戏的可玩性。此外,可以设计游戏初始画面和结束画面,添加鼠标控制等。以下是我的双人贪吃蛇设计: