}


CSquare::~CSquare(void)
    {
    ReleaseInterface(m_pITypeInfo);
    ReleaseInterface(m_pIUnkDisp);

    if (NULL!=m_hPenPos)
        DeleteObject(m_hPenPos);

    if (NULL!=m_hPenNeg)
        DeleteObject(m_hPenNeg);

    if (NULL!=m_hWnd)
        DestroyWindow(m_hWnd);

    return;
    }



/*
 * CSquare::Init
 *
 * Purpose:
 *  Creates the window in which we draw.
 */

BOOL CSquare::Init(HWND hWndOwner, HINSTANCE hInst)
    {
    ITypeLib       *pITypeLib;
    HRESULT         hr;

    //Create both default pens
    CreatePens(TRUE, TRUE);

    m_hWnd=CreateWindow(SZCLASSSQUARE, SZCLASSSQUARE
        , WS_CAPTION | WS_POPUP, m_xPos, m_yPos, m_cx, m_cy
        , hWndOwner, NULL, hInst, this);


    if (NULL==m_hWnd)
        return NULL;


    if (FAILED(LoadRegTypeLib(LIBID_SphereSquareLibrary, 1, 0
        , LANG_NEUTRAL, &pITypeLib)))
        {
        if (FAILED(LoadTypeLib(OLETEXT("SQUARE.TLB"), &pITypeLib)))
            return FALSE;
        }

    hr=pITypeLib->GetTypeInfoOfGuid(IID_ISphereSquare, &m_pITypeInfo);

    if (FAILED(hr))
        {
        pITypeLib->Release();
        return FALSE;
        }

    hr=CreateStdDispatch((IUnknown *)this, (ISphereSquare *)this
        , m_pITypeInfo, &m_pIUnkDisp);

    pITypeLib->Release();

    if (FAILED(hr))
        return FALSE;

    return TRUE;
    }




/*
 * CSquare::CreatePens
 *
 * Purpose:
 *  Creates one or both line color pens
 *
 * Parameters:
 *  fPositive       BOOL instructing us to create positive line color.
 *  fNegative       BOOL instructing us to create negative line color.
 *
 * Return Value:
 *  None
 */

void CSquare::CreatePens(BOOL fPositive, BOOL fNegative)
    {
    if (fPositive)
        {
        if (NULL!=m_hPenPos)
            DeleteObject(m_hPenPos);

        m_hPenPos=CreatePen(PS_SOLID, 1, m_crLinePos);

        if (NULL==m_hPenPos)
            m_hPenPos=(HPEN)GetStockObject(BLACK_PEN);
        }

    if (fNegative)
        {
        if (NULL!=m_hPenNeg)
            DeleteObject(m_hPenNeg);

        m_hPenNeg=CreatePen(PS_SOLID, 1, m_crLineNeg);

        if (NULL==m_hPenNeg)
            m_hPenNeg=(HPEN)GetStockObject(BLACK_PEN);
        }

    return;
    }




/*
 * CSquare::Draw
 *
 * Purpose:
 *  Draws the image of a square rotated according to m_dDeclin
 *  and m_dTheta with an edge length of m_cRadius.
 *
 * Parameters:
 *  hDC             HDC on which to draw.
 *
 * Return Value;
 *  None
 */

void CSquare::Draw(HDC hDC)
    {
    POINT           pt[5];
    int             x, y;
    double          rad;
    RECT            rc;
    HGDIOBJ         hGDI;

    SetBkColor(hDC, m_crBack);

    //Erase the background
    SetRect(&rc, 0, 0, m_xOrg*2, m_yOrg*2);
    ExtTextOut(hDC, 0, 0, ETO_OPAQUE, &rc, NULL, 0, NULL);

    rad=cos(m_dDeclin);

    x=(int)(m_cRadius*cos(m_dTheta));
    y=(int)(m_cRadius*rad*sin(m_dTheta));

    SETPOINT(pt[0], m_xOrg+x, m_yOrg+y);
    SETPOINT(pt[2], m_xOrg-x, m_yOrg-y);

    x=(int)(m_cRadius*cos(m_dTheta+PI/2));
    y=(int)(m_cRadius*rad*sin(m_dTheta+PI/2));

    SETPOINT(pt[3], m_xOrg+x, m_yOrg+y);
    SETPOINT(pt[1], m_xOrg-x, m_yOrg-y);

    pt[4]=pt[0];

    /*
     * Set the line color according to which side of the square
     * is facing out of the screen.  We'll draw the positive
     * z lines a yellow (default), the negative face red
     * (default).  Both colors can be changed by the controller.
     *
     * To determine which side is out, we only have to look at
     * the rad value which is cos(m_dDeclin).  If positive, then
     * we're in the positive range.
     */

    hGDI=SelectObject(hDC, (rad > 0) ? m_hPenPos : m_hPenNeg);
    Polyline(hDC, pt, sizeof(pt)/sizeof(POINT));

    SelectObject(hDC, GetStockObject(WHITE_PEN));
    MoveToEx(hDC, m_xOrg, m_yOrg, NULL);
    LineTo(hDC, pt[0].x, pt[0].y);

    SelectObject(hDC, hGDI);
    return;
    }




/*
 * SquareWndProc
 *
 * Purpose:
 *  Window procedure for the Square window.
 */

LRESULT APIENTRY SquareWndProc(HWND hWnd, UINT iMsg, WPARAM wParam
    , LPARAM lParam)
    {
    PCSquare    pcp;
    PAINTSTRUCT         ps;
    HDC                 hDC;
    RECT                rc;

    pcp=(PCSquare)GetWindowLong(hWnd, SQWL_STRUCTURE);

    switch (iMsg)
        {
        case WM_CREATE:
            pcp=(PCSquare)((LPCREATESTRUCT)lParam)
                ->lpCreateParams;
            SetWindowLong(hWnd, SQWL_STRUCTURE, (LONG)pcp);
            break;

        case WM_ERASEBKGND:
            hDC=(HDC)wParam;
            SetBkColor(hDC, pcp->m_crBack);
            GetClientRect(hWnd, &rc);
            ExtTextOut(hDC, 0, 0, ETO_OPAQUE, &rc, NULL, 0, NULL);
            break;

        case WM_PAINT:
            hDC=BeginPaint(hWnd, &ps);
            pcp->Draw(hDC);
            EndPaint(hWnd, &ps);
            break;

        case WM_CLOSE:
            /*
             * Eat this or Alt+F4 can destroy the window, even
             * though we don't have a system menu.
             */
            break;

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

    return 0L;
    }






/*
 * CSquare::QueryInterface
 * CSquare::AddRef
 * CSquare::Release
 *
 * Purpose:
 *  IUnknown members for CSquare object.
 */

STDMETHODIMP CSquare::QueryInterface(REFIID riid, PPVOID ppv)
    {
    *ppv=NULL;

    if (IID_IUnknown==riid || IID_ISphereSquare==riid)
        *ppv=this;

    if (IID_IDispatch==riid || DIID_DISphereSquare==riid)
        return m_pIUnkDisp->QueryInterface(IID_IDispatch, ppv);

    if (NULL!=*ppv)
        {
        ((IUnknown *)*ppv)->AddRef();
        return NOERROR;
        }

    return ResultFromScode(E_NOINTERFACE);
    }


STDMETHODIMP_(ULONG) CSquare::AddRef(void)
    {
    return ++m_cRef;
    }


STDMETHODIMP_(ULONG) CSquare::Release(void)
    {
    if (0L!=--m_cRef)
        return m_cRef;

    ObjectDestroyed();
    delete this;
    return 0L;
    }



//ISphereSquare members

STDMETHODIMP_(double) CSquare::get_Radius(void)
    {
    return m_cRadius;
    }

STDMETHODIMP_(void) CSquare::put_Radius(double cRadius)
    {
    //Only use positive radii.
    if (cRadius > 0.0)
        m_cRadius=cRadius;

    //We'll be lazy and not throw exceptions.
    return;
    }


STDMETHODIMP_(double) CSquare::get_Theta(void)
    {
    return m_dTheta;
    }

STDMETHODIMP_(void) CSquare::put_Theta(double dTheta)
    {
    //Anything is valid when you do trig
    m_dTheta=dTheta;
    return;
    }


STDMETHODIMP_(double) CSquare::get_Declination(void)
    {
    return m_dDeclin;
    }

STDMETHODIMP_(void) CSquare::put_Declination(double dDeclin)
    {
    m_dDeclin=dDeclin;
    return;
    }


STDMETHODIMP_(long) CSquare::get_BackColor(void)
    {
    return m_crBack;
    }

STDMETHODIMP_(void) CSquare::put_BackColor(long crBack)
    {
    m_crBack=crBack;
    return;
    }


STDMETHODIMP_(long) CSquare::get_LineColorPositive(void)
    {
    return m_crLinePos;
    }

STDMETHODIMP_(void) CSquare::put_LineColorPositive(long crLinePos)
    {
    m_crLinePos=crLinePos;
    return;
    }


STDMETHODIMP_(long) CSquare::get_LineColorNegative(void)
    {
    return m_crLineNeg;
    }

STDMETHODIMP_(void) CSquare::put_LineColorNegative(long crLineNeg)
    {
    m_crLineNeg=crLineNeg;
    return;
    }


STDMETHODIMP_(void) CSquare::Draw(void)
    {
    InvalidateRect(m_hWnd, NULL, FALSE);
    UpdateWindow(m_hWnd);
    return;
    }

STDMETHODIMP_(void) CSquare::SetCenterPoint(int cx, int cy)
    {
    //No validation...we're deing lazy
    m_xOrg=cx;
    m_yOrg=cy;
    return;
    }

STDMETHODIMP_(void) CSquare::ShowWindow(int nCmdShow)
    {
    ::ShowWindow(m_hWnd, nCmdShow);
    UpdateWindow(m_hWnd);
    return;
    }

STDMETHODIMP_(void) CSquare::SetWindowPosition(int xPos, int yPos)
    {
    m_xPos=xPos;
    m_yPos=yPos;

    SetWindowPos(m_hWnd, NULL, m_xPos, m_yPos, 0, 0
        , SWP_NOSIZE | SWP_NOZORDER | SWP_NOACTIVATE);
    return;
    }

STDMETHODIMP_(void) CSquare::SetWindowSize(int cx, int cy)
    {
    m_cx=cx;
    m_cy=cy;

    SetWindowPos(m_hWnd, NULL, 0, 0, m_cx, m_cy
        , SWP_NOMOVE | SWP_NOZORDER | SWP_NOACTIVATE);
    return;
    }