constant movement using arrow keys

Hi everyone. My name is Zvjezdan Veselinovic and I am studying Game and Simulation Programming at Rasmussen College over in New Port Richey, Florida. My question pertains to a "Tron-like" game that I am creating. It is called "Colors and Explosions". For my game, I have arrow key movement and a moving object. My question is: "How do I make it so that when I press an arrow key, my object will constantly move until I press another arrow key?" I need help on this. Any help would be appreciated, really.

Code:

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// My "Things_in_background.h" header file code

#include <iostream>
#include <string>
#include <windows.h> // resize the screen, gotoxy, delay, and so on.
#include <iomanip> // GetAsyncKeyState(), GetKeyState(), and so on.
#include <ctime>
#include <conio.h> // _getch(), _kbhit()

using namespace std;


int gotoxy(int x, int y) // used to place things anywhere in the window
{ 
    HANDLE hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
    COORD point;
      point.X = x-1;
    point.Y = y-1;   
      SetConsoleCursorPosition(hConsole, point);
      return SetConsoleCursorPosition(hConsole, point);
}


void Continue_() { cout << "Press any key to continue... "; _getch(); }
void Space_() { cout << "Press SPACE to continue... "; _getch(); }
void Clear_Line() { gotoxy(5,35); cout << "                                                            " << endl; }

void Up_arrow() { printf("%c", 30); }
void Down_arrow() { printf("%c", 31); }
void Left_arrow() { printf("%c", 17); }
void Right_arrow() { printf("%c", 16); }

void Object() { cout << "&" << endl; }

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Code:

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// my main_program.cpp file code

#include "Things_in_background.h"

struct Player_Presses
{
    char up_arrow, down_arrow, left_arrow, right_arrow;
};

int main()
{
    Player_Presses player1;

    char movement;

    int objectx = 2, objecty = 2;



    cout << "Press the Up arrow: "; player1.up_arrow = _getch();

    if(_kbhit())
    {
        player1.up_arrow = _getch(); Up_arrow();

        if(player1.up_arrow == GetAsyncKeyState(VK_UP))
        {
            player1.up_arrow = VK_UP;
        }
    } cout << endl << endl;



    cout << "Press the Down arrow: "; player1.down_arrow = _getch();

    if(_kbhit())
    {
        player1.down_arrow = _getch(); Down_arrow();

        if(player1.down_arrow == GetAsyncKeyState(VK_DOWN))
        {
            player1.down_arrow = VK_DOWN;
        }
    } cout << endl << endl;



    cout << "Press the Left arrow: "; player1.left_arrow = _getch();

    if(_kbhit())
    {
        player1.left_arrow = _getch(); Left_arrow();

        if(player1.left_arrow == GetAsyncKeyState(VK_LEFT))
        {
            player1.left_arrow = VK_LEFT;
        }
    } cout << endl << endl;



    cout << "Press the Right arrow: "; player1.right_arrow = _getch();

    if(_kbhit())
    {
        player1.right_arrow = _getch(); Right_arrow();

        if(player1.right_arrow == GetAsyncKeyState(VK_RIGHT))
        {
            player1.right_arrow = VK_RIGHT;
        }
    } cout << endl << endl << endl << endl;



    cout << "Your arrows are..." << endl << endl << endl;

    cout << "Up: " << player1.up_arrow << endl << endl;
    cout << "Down: " << player1.down_arrow << endl << endl;
    cout << "Left: " << player1.left_arrow << endl << endl;
    cout << "Right: " << player1.right_arrow << endl << endl;

    Space_(); system("cls");

    system("mode 100,40");

    gotoxy(5,35); Space_();
    Clear_Line();

    gotoxy(objectx,objecty); Object();

    a: gotoxy(5,35); cout << "Press any key to move piece: "; movement = _getch();


    if(_kbhit())
    {
        do {
        movement = _getch();

        if(movement == player1.up_arrow)
        {
            objecty--;
            gotoxy(objectx, objecty); Object();

            Clear_Line(); goto a;
        }
       
        if(movement == player1.down_arrow)
        {
            objecty++;
            gotoxy(objectx, objecty); Object();
            Clear_Line(); goto a;
        }

        if(movement == player1.left_arrow)
        {
            objectx--;
            gotoxy(objectx, objecty); Object();
            Clear_Line(); goto a;
        }

        if(movement == player1.right_arrow)
        {
            objectx++;
            gotoxy(objectx, objecty); Object();
            Clear_Line(); goto a;
        }

        } while(objectx != 20 || objectx != 1 || objecty != 1 || objecty != 25);

    } // end of _kbhit()

    gotoxy(5,35); Continue_();
    return 0;
}

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Thank You all for taking your time at looking at my code.

- Zvjezdan Veselinovic

my only advice here is do not use goto! break your do...while loop out into its own function and return from it in every case where you say goto a. then replace the a: line label with a while (true) loop.

so would I do a do whatever movement while previous movement != what I just typed in? Is that what you're going for?

Perhaps before you create a 100+ line program with 4 keys to deal with (which doesn't work), you prototype your idea with a single key.

Such as
- you run the program, it waits for a key press
- you press a key
- it prints
Moving
Moving
Moving
Moving
Moving
Moving
Moving
Moving
- you press another key and it stops.

Then you extend that to two keys, and print "Moving Up" or "Moving Down" as appropriate.

Ok. I'll try and prototype it. Thank You. =)

Personally I;d just use four boolians, one for each direction. When a key is pressed it sets that direction to true and all other to false. Your movement function should check the boolians rather than the keys when deciding how to move the object, hope it helps!