我一直在开发一个利用SDL 2的程序，我一直在尝试使用SDL_Surface将文本转换为SDL_Texture，然后使用SDL_RenderCopy()进行渲染。它只显示一个黑屏（如预期），但红色的“Hello World！“文本不会出现。这也是C++，澄清一下。
这是我的代码：

#include <iostream>
#include <SDL.h>
#include <SDL_ttf.h>

int main()
{
    bool quit = false;

    SDL_Event event;

    SDL_Init(SDL_INIT_EVERYTHING);
    TTF_Init();

    SDL_Window *window = SDL_CreateWindow("GUI Text Editor", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 640, 480, SDL_WINDOW_SHOWN);

    if(window == NULL)
    {
        std::cout << "window is null" << SDL_GetError();
    }

    SDL_Renderer *renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);

    SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);

    if(renderer == NULL)
    {
        std::cout << "renderer is null" << SDL_GetError();
    }

    SDL_Color red = {255, 0, 0, 255};

    TTF_Font *roboto = TTF_OpenFont("fonts/Roboto-Regular.ttf", 24);

    if(roboto == NULL)
    {
        std::cout << "font is null " << SDL_GetError();
    }

    SDL_Surface *textSurface = TTF_RenderText_Solid(roboto, "Hello World!", red);

    if(textSurface == NULL)
    {
        std::cout << "surface is null " << SDL_GetError();
    }

    SDL_Texture *textTexture = SDL_CreateTextureFromSurface(renderer, textSurface);

    if(textTexture == NULL)
    {
        std::cout << "texture is null " << SDL_GetError();
    }

    SDL_Rect rect;
    rect.x = 0;
    rect.y = 0;
    rect.w = 300;
    rect.h = 300;

    while (!quit)
    {
        while (SDL_PollEvent(&event) > 0)
        {
            switch (event.type)
            {
                case SDL_QUIT:
                    quit = true;
                    break;
            }
        }

        SDL_RenderCopy(renderer, textTexture, nullptr, &rect);

        SDL_UpdateWindowSurface(window);
    }

    SDL_Quit();
    TTF_Quit();

    return 0;
}

(The fonts文件夹与g++编译的可执行文件位于同一个工作目录中）
我期待着红色的“Hello World！”文本出现，但唉，它没有。
编辑：多亏了genpfault，我才能够得到文本的渲染，但是文本背后有奇怪的静态特性-可能是rect。
我的新代码：

#include <iostream>
#include <SDL.h>
#include <SDL_ttf.h>

int main()
{
    bool quit = false;

    SDL_Event event;

    SDL_Init(SDL_INIT_EVERYTHING);
    TTF_Init();

    SDL_Window *window = SDL_CreateWindow("GUI Text Editor", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 640, 480, SDL_WINDOW_SHOWN);

    if(window == NULL)
    {
        std::cout << "window is null" << SDL_GetError();
    }

    SDL_Renderer *renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);

    SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);

    if(renderer == NULL)
    {
        std::cout << "renderer is null" << SDL_GetError();
    }

    SDL_Color red = {255, 0, 0, 255};

    TTF_Font *roboto = TTF_OpenFont("fonts/Roboto-Regular.ttf", 24);

    if(roboto == NULL)
    {
        std::cout << "font is null " << SDL_GetError();
    }

    SDL_Surface *textSurface = TTF_RenderText_Solid(roboto, "Hello World!", red);

    if(textSurface == NULL)
    {
        std::cout << "surface is null " << SDL_GetError();
    }

    SDL_Texture *textTexture = SDL_CreateTextureFromSurface(renderer, textSurface);

    if(textTexture == NULL)
    {
        std::cout << "texture is null " << SDL_GetError();
    }

    SDL_Rect rect;
    rect.x = 0;
    rect.y = 0;
    rect.w = 300;
    rect.h = 300;

    while (!quit)
    {
        while (SDL_PollEvent(&event) > 0)
        {
            switch (event.type)
            {
                case SDL_QUIT:
                    quit = true;
                    break;
            }
        }

        SDL_RenderPresent(renderer);

        SDL_RenderCopy(renderer, textTexture, nullptr, &rect);

        SDL_UpdateWindowSurface(window);
    }

    SDL_Quit();
    TTF_Quit();

    return 0;
}

静态：