如何从数组中打印出文本（SDL_TTF）？

Question

我发布了我认为相关的部分代码。我正在尝试通过 SDL_TTF 为我的菜单绘制一些文本。每次单击按钮时，我都会从服务器获取一串字符。 “I1P1I2P1I3P1I4P1I5P1I6P1I7P1I8P1I9P1”之类的东西，“I1”表示大厅 1，P1 表示连接了 1 个玩家。但是我只想打印出“I1”然后有一堆空间说200像素然后打印出“P1”然后跳到下一行打印“I2”和“P1”。我尝试了文本变形，但它忽略了它并打印出整行文本。其次，我如何才能在“I1”和“P1”之间打印空格。有没有更简单/有效的方法来通过数组中的 SDL_TTF 打印文本？

typedef struct
{
    Menu menu;

    SDL_Texture     *label;
    SDL_Renderer    *rendererMenu;
    TTF_Font        *font;
    char            *lobbyResponse;
}   MenuState;

void dispayText(char *text, MenuState *menu)
{
    SDL_Color color         = {255, 255, 255, 255};
    SDL_Surface *surface    = TTF_RenderText_Blended_Wrapped(menu->font, text, color, 4);
    menu->label             = SDL_CreateTextureFromSurface(menu->rendererMenu, surface);
    menu->menu.labelW       = surface->w;
    menu->menu.labelH       = surface->h;
    //pos.x = x;
    //pos.y = y;
    SDL_FreeSurface(surface);
}



int processEventsMenu(SDL_Window *window, MenuState *menu, TCPsocket *tcpsock)
{
    SDL_Event ev;
    menu->lobbyResponse = malloc(sizeof(char[1024])); // <- moved it here for clarity

    while (SDL_PollEvent(&ev))
    {
        switch(ev.type)
        {
            case SDL_MOUSEBUTTONDOWN:
                if (ev.button.button == SDL_BUTTON_LEFT)
                {
                    SendLobbyMessage(tcpsock, refreshCommand);
                    ReceiveLobbyMessage(tcpsock, menu->lobbyResponse);
                    printf("Created lobby with id: %c\n",menu->lobbyResponse[0]);
                    dispayText(menu->lobbyResponse, menu);
                    printf("Lobbys: %c\n", menu->lobbyResponse[0]);
                }
        }
    }
}

Answer 1

puts("Something \t\t Something\n"); // \t allows to put "empty spaces" 

我建议在打印之前编写一个函数来格式化字符串。考虑使用strtok_r()。另一种解决方案是逐个字符迭代到字符串中，并在每次遇到| 时打印\n 以“跳到下一行”。

似乎对我有用的一种可能的解决方案是：

const char*         s = "I1P1I2P1I3P1I4P1I5P1I6P1I7P1I8P1I9P1";
const unsigned   size = strlen(s);
char*          result = malloc(sizeof(char) * (strlen(s) + 2 * strlen(s) / 4) + 1);
/* We allocated the memory necessary to put the whole of the string `s`
inside of the string `result`, and a tab and a newline, considering
that for every 4 characters inside of `s`, we will put 1 tab and 1
newline*/

int                 i = 0;
int                 j = 0;

while (i < size + 1)
{
    result[j] = s[i];
    if ((i + 1) % 2 == 0)       // Every 2 char that were passed from _s_ to _result_
    {
        if ((i + 1) % 4 == 0)
            result[++j] = '\n'; // Either we add a newline...
        else
            result[++j] = '\t'; // ... or we add a tab
    }
    j++;
    i++;
}
printf("Original String : %s\n", s);
printf("Formatted String : \n%s\n", result);

输出是：

Original String : I1P1I2P1I3P1I4P1I5P1I6P1I7P1I8P1I9P1
Formatted String : 
I1  P1
I2  P1
I3  P1
I4  P1
I5  P1
I6  P1
I7  P1
I8  P1
I9  P1

Answer 2

你可以在每个 n 字符后放置空格和换行符，因为你有一个规则的字符模式。您想要的是在前 2 个字符之后有一个空格（或制表符或其他），然后在接下来的 2 个字符之后有一个换行符，然后在接下来的 2 个字符之后有一个空格，在接下来的 2 个字符之后有一个换行符，等等。

对我来说，最简单的方法是一个简单的while 循环，它会逐个打印字符，并在需要打印一些空格或换行符时添加空格和换行符。

你可以遍历你想要格式化的字符串：

int     main(void)
{
    int      i = 0;
    int      j = 0;
    char*    s = "I1P1I2P1I3P1I4P1I5P1I6P1I7P1I8P1I9P1";

    while (s[j]) // while we have not reached the end of the string s
    {
        if ((i + 1) % 6 == 0)
            printf("\n");           // print a newline
        else if ((i + 1) % 3 == 0)
            printf("  ");           // print some spaces (or whatever you want)
        else
            printf("%c", s[j++]);   // print a character then increment the index of s
        i++;
    }
}

您还可以在程序正在编写的行中递增：

int main(void)
{
    int     j = 0;
    int     k = 0;        // k is the index of the line we're currently writing
    char*   s = "I1P1I2P1I3P1I4P1I5P1I6P1I7P1I8P1I9P1";
    while (s[j])
    {
        if (k == 5)       // If the program has already written 4 chars from s in the line...
        {
            printf("\n"); // ...go to a new line.
            k = 0;
        }
        else if (k == 2)  // If the program has already written 2 chars from s in the line...
        {
            printf(" ");  // ...add some spaces.
            k++;
        }
        else              // Else, print a char from s in the current line
        {
            printf("%c", s[j++]);
            k++;
        }
    }
}

输出：

I1  P1
I2  P1
I3  P1
I4  P1
I5  P1
I6  P1
I7  P1
I8  P1
I9  P1