BasicGL

main.cpp

#include <Windows.h>
#include <GL/gl.h>

#pragma comment(lib, "OpenGL32.lib")

LRESULT CALLBACK MyWndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)
    {
    case WM_CLOSE:
        ExitProcess(0);
    default:
        return DefWindowProc(hWnd, message, wParam, lParam);
    }
}

int CALLBACK WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
    WNDCLASSEX wc;
    ZeroMemory(&wc, sizeof(wc));
    wc.cbSize = sizeof(wc);
    wc.style = CS_OWNDC;
    wc.lpfnWndProc = MyWndProc;
    wc.hInstance = hInstance;
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH)COLOR_BACKGROUND;
    wc.lpszClassName = TEXT("WindowClass");
    RegisterClassEx(&wc);

    RECT wr = { 0, 0, 640, 480 };
    AdjustWindowRect(&wr, 0, FALSE);
    HWND hWnd = CreateWindowEx(
        0, TEXT("WindowClass"),
        TEXT("BasicGL"),
        WS_OVERLAPPEDWINDOW,
        0, 0, wr.right - wr.left, wr.bottom - wr.top,
        0, 0, hInstance, 0);

    PIXELFORMATDESCRIPTOR pfd;
    ZeroMemory(&pfd, sizeof(pfd));
    pfd.nSize = sizeof(pfd);
    pfd.nVersion = 1;
    pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER;
    pfd.iPixelType = PFD_TYPE_RGBA;
    pfd.cColorBits = 32;
    pfd.cDepthBits = 24;
    pfd.cStencilBits = 8;
    pfd.iLayerType = PFD_MAIN_PLANE;

    HDC hDC = GetDC(hWnd);
    
    int chosenPixelFormat = ChoosePixelFormat(hDC, &pfd);
    SetPixelFormat(hDC, chosenPixelFormat, &pfd);

    HGLRC hGLRC = wglCreateContext(hDC);
    wglMakeCurrent(hDC, hGLRC);

    ShowWindow(hWnd, SW_SHOWNORMAL);

    while (1)
    {
        MSG msg;
        while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
        {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }

        glClear(GL_COLOR_BUFFER_BIT);

        glBegin(GL_TRIANGLES);
            glColor3ub(255, 0, 0);
            glVertex2f(-1.0f, -1.0f);
            glColor3ub(0, 255, 0);
            glVertex2f(1.0f, -1.0f);
            glColor3ub(0, 0, 255);
            glVertex2f(0.0f, 1.0f);
        glEnd();

        SwapBuffers(hDC);
    }

    return 0;
}