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我一直试图让 Glew 和 opengl 3.2 在 win32 上下文中使用代码块（minGW）。我在这里找到了一个不错的小教程

由于我一直在尝试确定是否可以在代码块中编译 glew，因此我想在执行本教程之前先尝试一下源代码，看看它是否可行。

在稍微调整了代码之后，我尝试编译并得到了几个我以前从未见过的错误。它们如下

|In function 'bool createWindow(LPCWSTR, int, int)':|
|73|error: cannot convert 'LPCWSTR {aka const wchar_t*}' to 'LPCSTR {aka const char*}' in assignment|
|80|error: cannot convert 'LPCWSTR {aka const wchar_t*}' to 'LPCSTR {aka const char*}' for argument '2' to 'HWND__* CreateWindowExA(DWORD, LPCSTR, LPCSTR, DWORD, int, int, int, int, HWND, HMENU, HINSTANCE, LPVOID)'|
|In function 'int WinMain(HINSTANCE, HINSTANCE, LPSTR, int)':|
|105|warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]|
|110|error: '_TRUNCATE' was not declared in this scope|
|110|error: 'mbstowcs_s' was not declared in this scope|

我的代码是

include <iostream>
#include <Windows.h>

#ifndef GLEW_STATIC
#define GLEW_STATIC
#endif //GLEW_STATIC



#include <GL/glew.h>
#include <GL/wglew.h>

//using namespace std;
//
//int main()
//{
//    cout << "Hello world!" << endl;
//    return 0;
//}


#include "opengl_3.h"

OpenGLContext openglContext; // Our OpenGL Context class

bool running = true; // Whether or not the application is currently running

HINSTANCE hInstance; // The HINSTANCE of this application
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM); // Standard window callback

/**
    WndProc is a standard method used in Win32 programming for handling Window messages. Here we
    handle our window resizing and tell our OpenGLContext the new window size.
*/
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) {
    switch (message) {
        case WM_SIZE: // If our window is resizing
        {
            openglContext.reshapeWindow(LOWORD(lParam), HIWORD(lParam)); // Send the new window size to our OpenGLContext
            break;
        }

        case WM_DESTROY:
        {
            PostQuitMessage(0);
            break;
        }
    }

    return DefWindowProc(hWnd, message, wParam, lParam);
}

/**
    createWindow is going to create our window using Windows API calls. It is then going to
    create our OpenGL context on the window and then show our window, making it visible.
*/
bool createWindow(LPCWSTR title, int width, int height) {
    WNDCLASS windowClass;
    HWND hWnd;
    DWORD dwExStyle = WS_EX_APPWINDOW | WS_EX_WINDOWEDGE;

    hInstance = GetModuleHandle(NULL);

    windowClass.style = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;
    windowClass.lpfnWndProc = (WNDPROC) WndProc;
    windowClass.cbClsExtra = 0;
    windowClass.cbWndExtra = 0;
    windowClass.hInstance = hInstance;
    windowClass.hIcon = LoadIcon(NULL, IDI_WINLOGO);
    windowClass.hCursor = LoadCursor(NULL, IDC_ARROW);
    windowClass.hbrBackground = NULL;
    windowClass.lpszMenuName = NULL;
    windowClass.lpszClassName = title;

    if (!RegisterClass(&windowClass)) {
        return false;
    }

    hWnd = CreateWindowEx(dwExStyle, title, title, WS_OVERLAPPEDWINDOW,
      CW_USEDEFAULT, 0, width, height, NULL, NULL, hInstance, NULL);

    openglContext.create30Context(hWnd); // Create our OpenGL context on the given window we just created

    ShowWindow(hWnd, SW_SHOW);
    UpdateWindow(hWnd);

    return true;
}

/**
    WinMain is the main entry point for Windows based applications as opposed to 'main' for console
    applications. Here we will make the calls to create our window, setup our scene and then
    perform our 'infinite' loop which processes messages and renders.
*/
int WINAPI WinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR    lpCmdLine,
                     int       nCmdShow) {
    MSG msg;

    /**
        The following 6 lines of code do conversion between char arrays and LPCWSTR variables
        which are used in the Windows API.
    */
    char *orig = "OpenGL 3 Project"; // Our windows title
    size_t origsize = strlen(orig) + 1;
    const size_t newsize = 100;
    size_t convertedChars = 0;
    wchar_t wcstring[newsize];
    mbstowcs_s(&convertedChars, wcstring, origsize, orig, _TRUNCATE);

    createWindow(wcstring, 500, 500); // Create our OpenGL window

    openglContext.setupScene(); // Setup our OpenGL scene

    /**
        This is our main loop, it continues for as long as running is true
    */
    while (running)
    {
        if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) { // If we have a message to process, process it
            if (msg.message == WM_QUIT) {
                running = false; // Set running to false if we have a message to quit
            }
            else {
                TranslateMessage(&msg);
                DispatchMessage(&msg);
            }
        }
        else { // If we don't have a message to process
            openglContext.renderScene(); // Render our scene (which also handles swapping of buffers)
        }
    }

    return (int) msg.wParam;
}

（对不起文字墙）还有其他文件，但所有错误似乎都是从这里开始的。如果需要，我会发布其余的。

我还没有真正看到任何与此类似的错误，因此我进行了一些谷歌搜索，发现该错误是由编译器未设置为多字节（VS2010 中的设置）引起的。我环顾四周，在代码块中找不到任何此类设置。这段代码只能在 VS 中使用还是我错过了什么？我担心这可能与我的链接有关，因为我过去有很多问题。任何帮助，将不胜感激。

4

2 回答 2

9

CreateWindowEx在包含任何标题之前更改CreateWindowExW或定义宏。UNICODE

于 2012-08-05T04:56:19.020 回答
2

我从来没有使用过 minGW，所以把它和一大粒盐一起吃。（顺便说一句，VS Express 可以免费使用。）

Unicode/Ascii 决定很大程度上由 UNICODE 定义控制。因此，如果您#define UNICODE 1，或者可能在您的编译命令行中传递它，那么很有可能会解决您的问题。

于 2012-08-05T04:56:17.560 回答