[edon1337]

Hi,

I was trying to make a simple snake game with C++ but I'm encountering a problem, there's a spamming _ running around the screen without stopping, I tried an already made code from YouTube which is supposed to work but the same happened.

PHP Code:

#include <iostream>
#include <stdlib.h>
#include <conio.h>
#include <ctime>

using namespace std;

int MapX = 20;
int MapY = 20;

int SnakeX;
int SnakeY;

int FruitX;
int FruitY;

int Score;

bool gameOver;

// Map Over-view
/*
012345678911234567892
0: ########################### --> X
1: #                         #
2: #                         #
3: #                         #
4: #                         #
5: #                         #
6: #                         #
7: #                         # Y
8: ###########################*/

enum eDirections
{
    STOP = 0,
    UP,
    DOWN,
    LEFT,
    RIGHT
};

eDirections dir;

void Setup( )
{
    srand( time ( 0 ) );

    dir = STOP;

    SnakeX = MapX / 2;
    SnakeY = MapY / 2;

    FruitX = rand( ) % MapX;
    FruitY = rand( ) % MapY;

    Score = 0;
}

void DrawMap( )
{
    system( "cls" );

    int x, y;
    for( y = 0; y < MapY; y++ )
    {
        if( ( y == 0 || y == MapY - 1 ) ) // first or last row
        {
            for( x = 0; x < MapX; x++ ) // print X 10 times
            {
                cout << "#";
            }
        }

        else // 1-9 row
        {
            cout << "#"; // # which goes to the first space of the line

            int spaces;
            spaces = 0;

            while( spaces != MapX - 1 ) // keep putting spaces till we reach the end of the line - 1
            {
                if( spaces == SnakeX && y == SnakeY )
                {
                    cout << "O";
                }

                else if( spaces == FruitX && y == FruitY )
                {
                    cout << "F";
                }

                else
                {
                    cout << " ";
                }
                spaces++;
            }
            cout << "#"; // finally print # at the end of the line
        }
        cout << endl;
    }
}

void Input( )
{
    if( _kbhit( ) ) // keyboard key was used
    {
        switch( _getch( ) )
        {
        case 'a':
            {
                dir = LEFT;
                break;
            }

        case 'd':
            {
                dir = RIGHT;
                break;
            }

        case 'w':
            {
                dir = UP;
                break;
            }

        case 's':
            {
                dir = DOWN;
                break;
            }

        case 'x':
            {
                gameOver = true;
                break;
            }

        default:
            {
                break;
            }
        }
    }
}

void Logic( )
{
    switch( dir )
    {
    case LEFT:
        {
            SnakeX--;
        }

    case RIGHT:
        {
            SnakeX++;
        }

    case UP:
        {
            SnakeY--;
        }

    case DOWN:
        {
            SnakeY++;
        }
    }
}

int main( )
{
    Setup( );
    while( ! gameOver )
    {
        Input();
        Logic();
        DrawMap();
    }

    return 0;
} 


[Bacardi]

Interesting , I want to try also... you have YouTube link ?

Here one way hide console line
https://stackoverflow.com/questions/...=votes#tab-top

[edon1337]

Originally Posted by Bacardi Interesting , I want to try also... you have YouTube link ? Here one way hide console line https://stackoverflow.com/questions/...=votes#tab-top

The so called cursor isn't the problem, but it's constant movement around the screen is.

[klippy]

I don't really understand what's happening. Can you record it? I can't try out the code, there's no conio.h on Linux.

[HamletEagle]

Not the ideal place to get help with your homework, but w/e.

Now, you have some big crystal clear issues, wondering how you didn't catch them:
1.In Logic() you are not using break; in any switch case, meaning that moving up and left is going to do nothing, while moving down and right is working because of how you ordered the switch cases.
2.But you will quickly notice that if you fix the above mistake once you press one key the cursor will not move only one position, but it will move until it gets out of the board.
3.2 (and also your weird cursor movement) happens because you are always redrawing the map, while redrawing should be done only when you actually got some input.

(also _kbhit is not needed, _getch already waits for input)

[edon1337]

Originally Posted by HamletEagle Not the ideal place to get help with your homework, but w/e. Now, you have some big crystal clear issues, wondering how you didn't catch them: 1.In Logic() you are not using break; in any switch case, meaning that moving up and left is going to do nothing, while moving down and right is working because of how you ordered the switch cases. 2.But you will quickly notice that if you fix the above mistake once you press one key the cursor will not move only one position, but it will move until it gets out of the board. 3.2 (and also your weird cursor movement) happens because you are always redrawing the map, while redrawing should be done only when you actually got some input. (also _kbhit is not needed, _getch already waits for input)

Not homework, simply trying to learn new languages. Also most of the scripters here are also experienced C++ programmers.

My apologies, I haven't ever coded in C++ so that's why there's lots of mistakes. I'm going to fix the moving out of the map logic later.

I did as you told me and now it's okay, but I still don't get why it worked for the guy in the video but doesn't work when I use his code.

Video Link: https://www.youtube.com/watch?v=W1e5wO7XR2w&t=446s
Code:

PHP Code:

#include <iostream>
#include <conio.h>
#include <windows.h>
using namespace std;
bool gameOver;
const int width = 20;
const int height = 20;
int x, y, fruitX, fruitY, score;
int tailX[100], tailY[100];
int nTail;
enum eDirecton { STOP = 0, LEFT, RIGHT, UP, DOWN};
eDirecton dir;
void Setup()
{
    gameOver = false;
    dir = STOP;
    x = width / 2;
    y = height / 2;
    fruitX = rand() % width;
    fruitY = rand() % height;
    score = 0;
}
void Draw()
{
    system("cls"); //system("clear");
    for (int i = 0; i < width+2; i++)
        cout << "#";
    cout << endl;
 
    for (int i = 0; i < height; i++)
    {
        for (int j = 0; j < width; j++)
        {
            if (j == 0)
                cout << "#";
            if (i == y && j == x)
                cout << "O";
            else if (i == fruitY && j == fruitX)
                cout << "F";
            else
            {
                bool print = false;
                for (int k = 0; k < nTail; k++)
                {
                    if (tailX[k] == j && tailY[k] == i)
                    {
                        cout << "o";
                        print = true;
                    }
                }
                if (!print)
                    cout << " ";
            }
                 
 
            if (j == width - 1)
                cout << "#";
        }
        cout << endl;
    }
 
    for (int i = 0; i < width+2; i++)
        cout << "#";
    cout << endl;
    cout << "Score:" << score << endl;
}
void Input()
{
    if (_kbhit())
    {
        switch (_getch())
        {
        case 'a':
            dir = LEFT;
            break;
        case 'd':
            dir = RIGHT;
            break;
        case 'w':
            dir = UP;
            break;
        case 's':
            dir = DOWN;
            break;
        case 'x':
            gameOver = true;
            break;
        }
    }
}
void Logic()
{
    int prevX = tailX[0];
    int prevY = tailY[0];
    int prev2X, prev2Y;
    tailX[0] = x;
    tailY[0] = y;
    for (int i = 1; i < nTail; i++)
    {
        prev2X = tailX[i];
        prev2Y = tailY[i];
        tailX[i] = prevX;
        tailY[i] = prevY;
        prevX = prev2X;
        prevY = prev2Y;
    }
    switch (dir)
    {
    case LEFT:
        x--;
        break;
    case RIGHT:
        x++;
        break;
    case UP:
        y--;
        break;
    case DOWN:
        y++;
        break;
    default:
        break;
    }
    //if (x > width || x < 0 || y > height || y < 0)
    //  gameOver = true;
    if (x >= width) x = 0; else if (x < 0) x = width - 1;
    if (y >= height) y = 0; else if (y < 0) y = height - 1;
 
    for (int i = 0; i < nTail; i++)
        if (tailX[i] == x && tailY[i] == y)
            gameOver = true;
 
    if (x == fruitX && y == fruitY)
    {
        score += 10;
        fruitX = rand() % width;
        fruitY = rand() % height;
        nTail++;
    }
}
int main()
{
    Setup();
    while (!gameOver)
    {
        Draw();
        Input();
        Logic();
        Sleep(10); //sleep(10);
    }
    return 0;
} 


Besides from that, I managed to fix the spamming cursor, but now I'm trying to slow down the process of moving by using Sleep() but I'm not sure why it's not slowing it down

PHP Code:

#include <iostream>
#include <stdlib.h>
#include <conio.h>
#include <ctime>
#include <Windows.h>

using namespace std;

int MapX = 20;
int MapY = 20;

int SnakeX;
int SnakeY;

int FruitX;
int FruitY;

int Score;

bool gameOver;

// Map Over-view
/*
012345678911234567892
0: ########################### --> X
1: #                         #
2: #                         #
3: #                         #
4: #                         #
5: #                         #
6: #                         #
7: #                         # Y
8: ###########################*/

enum eDirections
{
    STOP = 0,
    UP,
    DOWN,
    LEFT,
    RIGHT
};

eDirections dir;

void Setup( )
{
    srand( time ( 0 ) );

    dir = STOP;

    SnakeX = MapX / 2;
    SnakeY = MapY / 2;

    FruitX = rand( ) % MapX;
    FruitY = rand( ) % MapY;

    Score = 0;
}

void DrawMap( )
{
    system( "cls" );

    int x, y;
    for( y = 0; y < MapY; y++ )
    {
        if( ( y == 0 || y == MapY - 1 ) ) // first or last row
        {
            for( x = 0; x < MapX; x++ ) // print X 10 times
            {
                cout << "#";
            }
        }

        else // 1-9 row
        {
            cout << "#"; // # which goes to the first space of the line

            int spaces;
            spaces = 0;

            while( spaces != MapX - 1 ) // keep putting spaces till we reach the end of the line - 1
            {
                if( spaces == SnakeX && y == SnakeY )
                {
                    cout << "O";
                }

                else if( spaces == FruitX && y == FruitY )
                {
                    cout << "F";
                }

                else
                {
                    cout << " ";
                }
                spaces++;
            }
            cout << "#"; // finally print # at the end of the line
        }
        cout << endl;
    }
}

void Logic( )
{
    switch( dir )
    {
    case LEFT:
        {
            SnakeX--;
            break;
        }

    case RIGHT:
        {
            SnakeX++;
            break;
        }

    case UP:
        {
            SnakeY--;
            break;
        }

    case DOWN:
        {
            SnakeY++;
            break;
        }
    }
}

int Input( )
{
    switch( _getch( ) )
    {
    case 'a':
        {
            dir = LEFT;
            break;
        }

    case 'd':
        {
            dir = RIGHT;
            break;
        }

    case 'w':
        {
            dir = UP;
            break;
        }

    case 's':
        {
            dir = DOWN;
            break;
        }

    case 'x':
        {
            gameOver = true;
            dir = STOP;

            break;
        }
    }
    Logic();
    return 1;
}

int main( )
{
    Setup( );
    while( ! gameOver )
    {
        if( Input( ) == 1 )
            DrawMap( );
    }

    return 0;
} 


[HamletEagle]

Now your Input() function never returns 0. It is working however because you moved Logic() after _getch which waits for input.

A better approach:

PHP Code:

int main()
{
    Setup();
    DrawMap();
    while (!gameOver)
    {
        if (Input() == 1)
        {
            Logic();
            DrawMap();
            Sleep(60 * 60);
        }
    }

    return 0;
} 


And

PHP Code:

int Input()
{
    switch (_getch())
    {
        case 'a':
        {
            dir = LEFT;
            return 1;
        }

        case 'd':
        {
            dir = RIGHT;
            return 1;
        }

        case 'w':
        {
            dir = UP;
            return 1;
        }

        case 's':
        {
            dir = DOWN;
            return 1;
        }

        case 'x':
        {
            gameOver = true;
            dir = STOP;

            return 1;
        }
    }
    
    return 0;
} 


Sleep takes the input in miliseconds. 10 miliseconds is nothing

[edon1337]

Originally Posted by HamletEagle Now your Input() function never returns 0. It is working however because you moved Logic() after _getch which waits for input. A better approach: PHP Code: int main() {     Setup();     DrawMap();     while (!gameOver)     {         if (Input() == 1)         {             Logic();             DrawMap();             Sleep(60 * 60);         }     }     return 0; }  And PHP Code: int Input() {     switch (_getch())     {         case 'a':         {             dir = LEFT;             return 1;         }         case 'd':         {             dir = RIGHT;             return 1;         }         case 'w':         {             dir = UP;             return 1;         }         case 's':         {             dir = DOWN;             return 1;         }         case 'x':         {             gameOver = true;             dir = STOP;             return 1;         }     }          return 0; }  Sleep takes the input in miliseconds. 10 miliseconds is nothing

Thanks a bunch! I'm on my way to perfecting it now by adding more logic and options to it.

[HamletEagle]

As a side note, you should avoid to use global variables when they are not really needed.
You may need them when writing plugins because we are working with external events so we can't pass whatever variables we may need to them, but in most other cases you work only with functions you created so you have control over what arguments they take.

[edon1337]

Originally Posted by HamletEagle As a side note, you should avoid to use global variables when they are not really needed. You may need them when writing plugins because we are working with external events so we can't pass whatever variables we may need to them, but in most other cases you work only with functions you created so you have control over what arguments they take.

By 'external events' you mean the private functions? I'm sure all of the variables I've created must be global (score, gameOver, coordinates)