Xcode：SDL2 + OpenGL 3.2：窗口不会显示在示例代码中

Question

自从SDL2刚刚发布以来，我只是想尝试一下。在OSX 10.8.4上使用xcode，我正在编译wiki（here）上的SDL2 + OpenGL3.2示例。

除了没有窗口显示外，一切都顺利进行。我添加了一个在输出控制台中可见的基本跟踪（“第一计时器”，“第二计时器”等）。有没有想过为什么会发生这种情况？

XCode项目：

这是 main.cpp ：

#include <iostream>

#include <SDL2/SDL.h>
#include <OpenGL/gl3.h>


/* A simple function that prints a message, the error code returned by SDL,
 * and quits the application */
void sdldie(const char *msg)
{
    std::cout << msg << SDL_GetError() << std::endl;
    SDL_Quit();
    exit(1);
}

void checkSDLError(int line = -1)
{
#ifndef NDEBUG
    const char *error = SDL_GetError();
    if (*error != '\0')
    {
        printf("SDL Error: %s\n", error);
        if (line != -1)
            printf(" + line: %i\n", line);
        SDL_ClearError();
    }
#endif
}


int main(int argc, char *argv[]) {

    SDL_Window *mainwindow; /* Our window handle */
    SDL_GLContext maincontext; /* Our opengl context handle */

    if (SDL_Init(SDL_INIT_VIDEO) < 0) /* Initialize SDL's Video subsystem */
        sdldie("Unable to initialize SDL"); /* Or die on error */

    /* Request opengl 3.2 context.
     * SDL doesn't have the ability to choose which profile at this time of writing,
     * but it should default to the core profile */
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);

    /* Turn on double buffering with a 24bit Z buffer.
     * You may need to change this to 16 or 32 for your system */
    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
    SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);

    /* Create our window centered at 512x512 resolution */
    mainwindow = SDL_CreateWindow("Test SDL2", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
                                  512, 512, SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN);
    if (!mainwindow) /* Die if creation failed */
        sdldie("Unable to create window");

    checkSDLError(__LINE__);

    /* Create our opengl context and attach it to our window */
    maincontext = SDL_GL_CreateContext(mainwindow);
    checkSDLError(__LINE__);


    /* This makes our buffer swap syncronized with the monitor's vertical refresh */
    SDL_GL_SetSwapInterval(1);

    /* Clear our buffer with a red background */
    glClearColor ( 1.0, 0.0, 0.0, 1.0 );
    glClear ( GL_COLOR_BUFFER_BIT );
    /* Swap our back buffer to the front */
    SDL_GL_SwapWindow(mainwindow);
    /* Wait 2 seconds */
    std::cout << "First timer" << std::endl;
    SDL_Delay(2000);

    /* Same as above, but green */
    glClearColor ( 0.0, 1.0, 0.0, 1.0 );
    glClear ( GL_COLOR_BUFFER_BIT );
    SDL_GL_SwapWindow(mainwindow);
    std::cout << "Second timer" << std::endl;
    SDL_Delay(2000);

    /* Same as above, but blue */
    glClearColor ( 0.0, 0.0, 1.0, 1.0 );
    glClear ( GL_COLOR_BUFFER_BIT );
    SDL_GL_SwapWindow(mainwindow);
    std::cout << "Third timer" << std::endl;
    SDL_Delay(2000);

    /* Delete our opengl context, destroy our window, and shutdown SDL */
    SDL_GL_DeleteContext(maincontext);
    SDL_DestroyWindow(mainwindow);
    SDL_Quit();

    return 0;
}

Answer 1

问题解决了！

创建一个新的C ++控制台应用程序。 然后执行以下操作：

目标构建设置：

源代码组织：