在这个简单的C ++游戏中，我怎么去另一个“地图”？

Question

So, the problem is the following: I have set up arrays as "map"s, in which the player (@) can move. But how could I make the program switch maps, when, for example the player hits a coordinate, like [4] and [19]?

#include <iostream>
#include <windows.h>
using namespace std;

char plyr = '@';

char map[10][20] = {
    "###################",
    "#@                #",
    "#                 #",
    "#                  ",
    "#                  ",
    "#                 #",
    "#                 #",
    "#                 #",
    "###################"
};

char map2[10][20] = {
    "###################",
    "#  #############  #",
    "#     ##           ",
    "                   ",
    "                  #",
    "#                 #",
    "#              ####",
    "#           #######",
    "###################"

};


int x = 1;
int y = 1;

bool gameRunning = true;

int main(){

    while(gameRunning == true){
        system("cls");
        for(int disp=0; disp<10; disp++){
            cout << map[disp] << endl;  
        }

        system("pause>nul");    


        if(GetAsyncKeyState(VK_DOWN)){
                int y2 = y+1;
                if(map[y2][x] == ' '){
                    map[y][x] = ' ';
                    y++;
                    map[y][x] = plyr;
            }
        }

        if(GetAsyncKeyState(VK_UP)){
            int y2 = y-1;
            if(map[y2][x] == ' '){
                map[y][x] = ' ';
                y--;
                map[y][x] = plyr;   
            }
        }

        if(GetAsyncKeyState(VK_RIGHT)){
            int x2 = x+1;
            if(map[y][x2] == ' '){
                map[y][x] = ' ';
                x++;
                map[y][x] = plyr;
        }       
    }   

    if(GetAsyncKeyState(VK_LEFT)){
        int x2 = x-1;
        if(map[y][x2] == ' '){
            map[y][x] = ' ';
            x--;
            map[y][x] = plyr;
        }       
    }
}



    return 0;
}

Answer 1

What you need is some way to abstract out the currently used map. You can do it by keeping a pointer to current map, or by using a function which will return a reference to current map - index variable will indicate which map is current.

So when your user reaches coordinate, you should update current map index/pointer to a new one. You might also want to store somewhere information, which new map should be used. Below are few aproaches, but there are more.

decltype(map)& get_map(int map_index) {
    switch(map_index) {
      case 1:        
      return map;
      case 2:
      default:
        return map2;
    }
}

struct map_obj {
    int current_map;
    decltype(map[0])& operator[](int ind1) {   
        auto& mp = get_map(current_map);
        return mp[ind1];
    }
};

int main()
{
    // mathod1: Pointer to the current map
    char (*cur_map)[10][20] = ↦
    if ( (*cur_map)[9][19] == '#' ) {}

    // mathod1: Also pointer to current map, but using decltype
    decltype(map)* cur_map2 = ↦
    if ( (*cur_map2)[9][19] == '#' ) {}

    // mathod2: Use function which returns reference to current map
    int current_map = 0;
    if ( get_map(current_map)[9][19] == '#' ) {}

    // mathod3: Use object which uses operator[] to return row for specified column
    map_obj mp;
    mp.current_map = 1;
    if ( mp[9][19] == '#' ) {}
}

Answer 2

You could add another dimension to the array like this:

#include <iostream>

char map[2][10][20] =
{
    {
        "###################",
        "#@                #",
        "#                 #",
        "#                  ",
        "#                  ",
        "#                 #",
        "#                 #",
        "#                 #",
        "###################"
    }
,
    {
        "###################",
        "#  #############  #",
        "#     ##           ",
        "                   ",
        "                  #",
        "#                 #",
        "#              ####",
        "#           #######",
        "###################"
    }
};

void display_map(int level)
{
    std::cout << "level: " << (level + 1) << '\n';

    for(int y = 0; y < 9; ++y)
        std::cout << map[level][y] << '\n';
}

int main()
{
    // Display both maps:

    for(int level = 0; level < 2; ++level)
    {
        display_map(level);

        std::cout << '\n';
    }
}