贪吃蛇窗口文字闪烁的问题

Question

#include<stdio.h>
#include <stdlib.h>
#include <graphics.h>
#include<conio.h>

#define SNAKE_NUM 500
enum DIR
{
UP,
DOWN,
LEFT,
RIGHT,
};
struct Snake
{
int size;
int dir;
int speed;
POINT coor[SNAKE_NUM];
}snake;

struct Food
{
int x;
int y;
int r;
int grade;
bool flag;
DWORD color;
}food;
//数据的初始化
void GameInit()
{
// 初始化窗口
initgraph(640,480);
srand(GetTickCount());
snake.size=3;
snake.speed=10;
snake.dir=RIGHT;
for(int i=0;i<snake.size;i++)
{
snake.coor[i].x=40-10*i;
snake.coor[i].y=10;

}

food.x=rand()%640;
food.y=rand()%480;
food.color=RGB(rand()%256,rand()%256,rand()%256);
food.r=rand()%10+5;
food.flag=true;
    

}

void GameDraw()
{

BeginBatchDraw();   
setbkcolor(RGB(211,241,240));   
cleardevice();  
setfillcolor(YELLOW);   
for(int i=0;i<snake.size;i++)
{
    solidcircle(snake.coor[i].x,snake.coor[i].y,5);   
}
if(food.flag)
{
    solidcircle(food.x,food.y,food.r);
}
EndBatchDraw(); 

}
//移动蛇
void snakeMove()
{

for(int i=snake.size-1;i>0;i--)
{
    snake.coor[i]=snake.coor[i-1]; 
}
switch(snake.dir)
{
case UP:
    snake.coor[0].y-=snake.speed;
    if(snake.coor[0].y+10<=0)   
    {
        snake.coor[0].y=480;
    }
    break; 
case DOWN:
    snake.coor[0].y+=snake.speed;
    if(snake.coor[0].y-10>=480)
    {
        snake.coor[0].y=0;
    }
    break; 
case LEFT:
    snake.coor[0].x-=snake.speed;
    if(snake.coor[0].x+10<=0)
    {
        snake.coor[0].x=640;
    }
    break; 
case RIGHT:
    snake.coor[0].x+=snake.speed;
    if(snake.coor[0].x-10>=640)
    {
        snake.coor[0].x=0;
    }
    break; 
}

}

void keyControl()
{

if(_kbhit())
{
    switch (_getch())
    {
    case 'w':
    case 'W':
    case  72:
        
        if(snake.dir!=DOWN)  //防止反向操作 
        {
            snake.dir=UP;
        } 
        break;
    case 's':
    case 'S':
    case  80:
        if(snake.dir!=UP)
        {
            snake.dir=DOWN;
        } 
        break;
    case 'a':
    case 'A':
    case  75:
        if(snake.dir!=RIGHT)
        {
            snake.dir=LEFT;
        } 
        break;
    case 'd':
    case 'D':
    case  77:
        if(snake.dir!=LEFT)
        {
            snake.dir=RIGHT;
        }
        break;
    case ' ':
        while(1)
        {
            if(_getch()==' ')
                return;
        }
        break;
     } 
}

}
void EatFood()
{

if(food.flag && snake.coor[0].x>=food.x-food.r && snake.coor[0].x<=food.x+food.r&&
   snake.coor[0].y>=food.y-food.r && snake.coor[0].y<=food.y+food.r)
{
    food.flag=false;
    snake.size++;
    food.grade+=10;
}

if(!food.flag)
{
    food.x=rand()%640;
    food.y=rand()%480;
    food.color=RGB(rand()%256,rand()%256,rand()%256);
    food.r=rand()%10+5;
    food.flag=true;            
}

}

void showGrade()
{
char grade[20]="";
sprintf(grade,"grade: %d",food.grade);
settextcolor(BLACK);
settextstyle(20,0,"楷体");
outtextxy(550,19,grade);
}

int main()
{
GameInit();
while(1)
{
snakeMove();
GameDraw();
keyControl();
EatFood();
showGrade();
Sleep(50);
}

return 0;

}

Answer 1

showGrade();放到 GameDraw()的EndBatchDraw();前。