Win32 client size and an incorrect size

Question

So for a game project I am creating a game window (of course), but I only know the client size of the window and not the actual size. I know how to calculate the size but I am getting incorrect results when I am testing to see the size of the client area (should be the same as the input).

void NewWindow(width, height)
{
    // Code setting things up here.
        if (!fullscreen) // Convert client size to window size.
        {
            style = WS_OVERLAPPEDWINDOW;

            RECT r = RECT();
            r.top = 0;
            r.bottom = height;
            r.left = 0;
            r.right = width;

            AdjustWindowRect(&r, WS_CAPTION | WS_SYSMENU | WS_THICKFRAME | WS_MINIMIZEBOX |     WS_MAXIMIZEBOX, FALSE);

            w = r.right;
            h = r.bottom;
        }

        hWnd = CreateWindow(CLASS_NAME, title, style, CW_USEDEFAULT, CW_USEDEFAULT, w, h, NULL, NULL, GetModuleHandle(NULL), (LPVOID)NULL);
}

And the code for getting the client size is:

Size Game::GetClientSize()
{
    RECT r = RECT();
    GetClientRect(hWnd, &r);

    return Size(r.right - r.left, r.bottom - r.top);
}

I am not sure where the problem is, because AdjustWindowRect seems to be outputting a value larger than what I put in...

Thanks, Philip

Answer 1

The style you pass to AdjustWindowRect should be the same style you pass to CreateWindow. Otherwise they will mismatch. You also need to calculate width as right - left, and height as bottom - top, since the adjusted rect usually has a negative origin relative to the origin of the client area.