Making a custom titlebar

support
7

Hey, so finally I was able to find a soluion. Figuring out a solution completely drained my energy :sweat_smile: :sweat_smile: .

Anyway here is the final code that I used to remove the titlebar on windows. I also implemented the same thing for macos and linux but I wont post them since I dont know if they work.

WNDPROC original_proc;

LRESULT CALLBACK WindowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    switch (uMsg)
    {
        case WM_NCCALCSIZE:
        {
            // Remove the window's standard sizing border
            if (wParam == TRUE && lParam != NULL)
            {
                NCCALCSIZE_PARAMS* pParams = reinterpret_cast<NCCALCSIZE_PARAMS*>(lParam);
                pParams->rgrc[0].top += 1;
                pParams->rgrc[0].right -= 2;
                pParams->rgrc[0].bottom -= 2;
                pParams->rgrc[0].left += 2;
            }
            return 0;
        }
        case WM_NCPAINT:
        {
            // Prevent the non-client area from being painted
            return 0;
        }
        case WM_NCHITTEST:
        {
            // Expand the hit test area for resizing
            const int borderWidth = 8; // Adjust this value to control the hit test area size

            POINTS mousePos = MAKEPOINTS(lParam);
            POINT clientMousePos = { mousePos.x, mousePos.y };
            ScreenToClient(hWnd, &clientMousePos);

            RECT windowRect;
            GetClientRect(hWnd, &windowRect);

            if (clientMousePos.y >= windowRect.bottom - borderWidth)
            {
                if (clientMousePos.x <= borderWidth)
                    return HTBOTTOMLEFT;
                else if (clientMousePos.x >= windowRect.right - borderWidth)
                    return HTBOTTOMRIGHT;
                else
                    return HTBOTTOM;
            }
            else if (clientMousePos.y <= borderWidth)
            {
                if (clientMousePos.x <= borderWidth)
                    return HTTOPLEFT;
                else if (clientMousePos.x >= windowRect.right - borderWidth)
                    return HTTOPRIGHT;
                else
                    return HTTOP;
            }
            else if (clientMousePos.x <= borderWidth)
            {
                return HTLEFT;
            }
            else if (clientMousePos.x >= windowRect.right - borderWidth)
            {
                return HTRIGHT;
            }

            break;
        }
    }
    
    return CallWindowProc(original_proc, hWnd, uMsg, wParam, lParam);
}
void disableTitlebar(GLFWwindow* window)
{
    HWND hWnd = glfwGetWin32Window(window);

    LONG_PTR lStyle = GetWindowLongPtr(hWnd, GWL_STYLE);
    lStyle |= WS_THICKFRAME;
    lStyle &= ~WS_CAPTION;
    SetWindowLongPtr(hWnd, GWL_STYLE, lStyle);

    RECT windowRect;
    GetWindowRect(hWnd, &windowRect);
    int width = windowRect.right - windowRect.left;
    int height = windowRect.bottom - windowRect.top;

    original_proc = (WNDPROC)GetWindowLongPtr(hWnd, GWLP_WNDPROC);
    (WNDPROC)SetWindowLongPtr(hWnd, GWLP_WNDPROC, reinterpret_cast<LONG_PTR>(WindowProc));
    SetWindowPos(hWnd, NULL, 0, 0, width, height, SWP_FRAMECHANGED | SWP_NOMOVE);
}

With this code, you can basically keep all the native functionnality of glfw and windows like snapping the window or resizing and I think you still have rounded corners in windows11(I have to verify that).