c ++ opengl三角形没有显示

Question

我已经按照教程（我是opengl的新手），由于某种原因三角形没有显示...我会感激任何建议:)。 它编译没有警告，glClearColor如果我改变它，但没有显示三角形。

#include "GphEditorWindow.h"
#include "gl\GL.h"
#include "gl\GLU.h"

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR plCmdLine, int nCmdShow)
{
    POINT windowPos = { 100, 100 };
    POINT windowSize = { 800, 600 };

    if (!editorWindow.Init(hInstance, windowPos, windowSize))
{
    MessageBox(NULL, "EditorWindow init failed", "Graphite Editor", MB_OK | MB_ICONERROR);
    return ERROR_APP_INIT_FAILURE;
}
else
{
    return editorWindow.Run();
}

    return 0;
}

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    return editorWindow.WndProc(hWnd, message, wParam, lParam);
}

LRESULT EditorWindow::WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)
    {
        case WM_DESTROY:
            PostQuitMessage(0);
            break;

        case WM_SIZE:
            RECT rect;
            GetClientRect(hWnd, &rect);
            workspaceWth = rect.right - rect.left;
            workspaceHgh = rect.bottom - rect.top;
            break;

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

    return 0L;
}

LRESULT EditorWindowGL::WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    long result = EditorWindow::WndProc(hWnd, message, wParam, lParam);

    switch (message)
    {
        case WM_CREATE:
            if (!InitWGL(hWnd))
            {
                MessageBox(NULL, "Rendering Context Creation Failed!", "Graphite Editor", MB_OK | MB_ICONERROR);
                return ERROR_APP_INIT_FAILURE;
            }
            SceneSetup(false);
            ShowTitleBarInfo(hWnd);
            break;

        case WM_DESTROY:
            DeleteWGL();
            break;

        case WM_SIZE:
            SceneSetup(false);
            break;

        case WM_PAINT:
            DrawScene();
            ValidateRect(hWnd, NULL);
            break;
    }
    return result;
}

bool EditorWindow::Init(HINSTANCE editorHandler, POINT editorWindowPos, POINT editorWindowSize)
{
    char editorWindowName[] = "Graphite Editor";

    WNDCLASSEX wc;
    wc.cbSize = sizeof(wc);
    wc.style = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;
    wc.lpfnWndProc = (WNDPROC)::WndProc;
    wc.cbClsExtra = 0;
    wc.cbWndExtra = 0;
    wc.hInstance = editorHandler;
    wc.hIcon = NULL;
    wc.hIconSm = NULL;
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = NULL;
    wc.lpszMenuName = NULL;
    wc.lpszClassName = editorWindowName;

    if (RegisterClassExA(&wc) == 0)
    {
        DWORD blah = GetLastError();
        return false;
    }

    editorWindowHandler = CreateWindow(editorWindowName, editorWindowName, WS_OVERLAPPEDWINDOW,     editorWindowPos.x, editorWindowPos.y, editorWindowSize.x, editorWindowSize.y, NULL, NULL, editorHandler, NULL);

    if (editorWindowHandler == NULL)
        return false;
    ShowWindow(editorWindowHandler, SW_SHOW);
    UpdateWindow(editorWindowHandler);

    return true;
}

WPARAM EditorWindow::Run()
{
    MSG msg;
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return msg.wParam;
}

bool EditorWindowGL::PixelFormatSet(HDC dcHandler) const
{
    PIXELFORMATDESCRIPTOR pixelFormatDesc;
    ZeroMemory(&pixelFormatDesc, sizeof(pixelFormatDesc));
    pixelFormatDesc.nVersion = 1;
    pixelFormatDesc.dwFlags = PFD_SUPPORT_OPENGL | PFD_DRAW_TO_WINDOW | PFD_DOUBLEBUFFER;
    pixelFormatDesc.iPixelType = PFD_TYPE_RGBA;
    pixelFormatDesc.cColorBits = 32;
    pixelFormatDesc.cDepthBits = 32;
    pixelFormatDesc.iLayerType = PFD_MAIN_PLANE;

    int pixelFormat = ChoosePixelFormat(dcHandler, &pixelFormatDesc);

    if (pixelFormat == 0)
        return false;

    if (!SetPixelFormat(dcHandler, pixelFormat, &pixelFormatDesc))
        return false;

    return true;
}

bool EditorWindowGL::InitWGL(HWND windowHandler)
{
    dcHandler = ::GetDC(windowHandler);

    if (!PixelFormatSet(dcHandler))
        return false;

    rcHandler = wglCreateContext(dcHandler);
    if (rcHandler == NULL)
        return false;

    if (!wglMakeCurrent(dcHandler, rcHandler))
        return false;

    return true;
}

void EditorWindowGL::DeleteWGL()
{
    wglMakeCurrent(NULL, NULL);
    wglDeleteContext(rcHandler);
    ::ReleaseDC(editorWindowHandler, dcHandler);
}


void EditorWindowGL::ShowTitleBarInfo(HWND windowHandler)
{
    char buffer[256]; 
    GetWindowText(windowHandler, buffer, 256);
    const GLubyte* version = glGetString(GL_VERSION);
    strcat_s(buffer, " | OpenGL");
    strcat_s(buffer, (char*)version);
    const GLubyte* vendor = glGetString(GL_VENDOR);
    strcat_s(buffer, " | ");
    strcat_s(buffer, (char*)vendor);
    const GLubyte* gpu = glGetString(GL_RENDERER);
    strcat_s(buffer, " | "); strcat_s(buffer, (char*)gpu);
    SetWindowText(windowHandler, buffer);
}

void EditorWindowGL::SceneSetup(bool isometric)
{
    glViewport(0, 0, workspaceWth, workspaceHgh);

    glMatrixMode(GL_PROJECTION);
    glLoadIdentity;
    float aspect = workspaceHgh / (float)workspaceWth;

    if (!isometric)
        glFrustum(-1.0f, 1.0f, aspect * -1.0f, aspect * 1.0f, 1.0f, 10.0f);
    else
        glOrtho(-1.0f, 1.0f, aspect * -1.0f, aspect * 1.0f, 1.0f, 10.0f);

    glMatrixMode(GL_MODELVIEW);

    glEnable(GL_DEPTH_TEST);
}

void EditorWindowGL::DrawScene()
{
    const float x0 = 1.0f;
    const float y0 = 1.0f;
    const float z0 = 1.0f;

    glClearColor(0.125f, 0.125f, 0.125f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glLoadIdentity();
    glTranslatef(0.0f, 0.0f, -3.0f);

    glColor4f(1.0f, 1.0f, 1.0f, 1.0f);

    glBegin(GL_TRIANGLES);
    glVertex3f(-x0, -y0, 0.0f);
    glVertex3f(x0, -y0, 1.0f);
    glVertex3f(x0, y0, 0.0f);

    glEnd();
    SwapBuffers(dcHandler);
}