Method OnMouseMove

ColorCop/ColorCopDlg.cpp:1748–1897

}

void CColorCopDlg::OnMouseMove(UINT nFlags, CPoint point) {
    CString strStatus;

    //
    // Handle capture for eyedropper or magnifier
    //
    if (m_isEyedropping || m_isMagnifying) {
        if (::GetCapture() == nullptr) {
            SetCapture();
        } else {
            ClientToScreen(&point);  // convert to screen coordinates
        }
    }

    //
    // Eyedropper mode
    //
    if (m_isEyedropping) {
        bool skipColor = false;

        if (m_InitialMove) {
            AdvanceColorHistory();
            m_InitialMove = FALSE;
        }

        WindowDC hdc(nullptr);  // RAII DC

        if (m_Appflags & Sampling1) {
            const COLORREF crefxy = ::GetPixel(hdc, point.x, point.y);

            if (crefxy != CLR_INVALID) {
                const COLORREF current = RGB(m_Reddec, m_Greendec, m_Bluedec);

                if (current != crefxy) {
                    m_Reddec = GetRValue(crefxy);
                    m_Greendec = GetGValue(crefxy);
                    m_Bluedec = GetBValue(crefxy);

                    UpdateCMYKFromRGB(m_Reddec, m_Greendec, m_Bluedec);
                } else {
                    skipColor = true;
                }
            }
        } else {
            // 3×3, 5×5, or multi‑pixel sampling
            skipColor = AveragePixelArea(hdc, &m_Reddec, &m_Greendec, &m_Bluedec, point);
            UpdateCMYKFromRGB(m_Reddec, m_Greendec, m_Bluedec);
        }

        //
        // Relative‑position mode
        //
        if (bRelativePosition) {
            RelativePointEnd = point;

            int dx = point.x - RelativePoint.x;
            int dy = point.y - RelativePoint.y;