Отображение изображения

void DrawLineFunc(HWND hWnd, HDC hDc, int x, int y1, int y2, COLORREF clr)
{
    Pnt.x = 1;
    Pnt.y = 1;

    lPen.lopnStyle = PS_STYLE_MASK;
    lPen.lopnColor = clr;
    lPen.lopnWidth = Pnt;

    hDc = GetDC(hWnd);
    hPen = CreatePenIndirect(&lPen);
    SelectObject(hDc, hPen);

    MoveToEx(hDc, x, y1, &Pnt);
    LineTo(hDc, x, y2);
}

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    int wmId, wmEvent;
    PAINTSTRUCT ps;
    HDC hdc;
    HANDLE handle;

    switch (message)
    {
    case WM_COMMAND:
        wmId    = LOWORD(wParam);
        wmEvent = HIWORD(wParam);
       
        switch (wmId)
        {
        case IDM_about :
            DialogBox(hInst, (LPCTSTR)IDD_ABOUTBOX, hWnd, (DLGPROC)About);
            break;
        case ID_FILE_OPEN:
            LPTSTR fname;
            fname=PAlloc(250);
            FGetDirectory(fname);
            LoadBMTrue(hWnd, fname, bitmap);
            PDeAlloc((HLOCAL)fname);
            break;
        case ID_FILE_SAVE:
            OpenFileName(hWnd, handle);
            break;
        case ID_LINES_GRAY256:
            ConvertGray256(image_dc);
            break;
        case ID_DRAW_ELLIPSE:
            DrawEllipseFunc(hWnd, image_dc);
            break;
        case ID_DRAW_SQUARE:
            DrawSquareFunc(hWnd, image_dc);
            break;
        case ID_DRAW_LINE:
            DrawLineFunc(hWnd, image_dc, 50, 50, 200, 0x00FFFFFF);
            break;
        case ID_LINES_CODE:
            DialogBox(hInst, (LPCTSTR)IDD_ENTER_TEXT, hWnd, (DLGPROC)Code);
            break;
        case IDM_EXIT:
            DestroyWindow(hWnd);
            break;
        default:
            return DefWindowProc(hWnd, message, wParam, lParam);
        }
        break;
    case WM_PAINT:
        hdc = BeginPaint(hWnd, &ps);
        BitBlt(hdc,50,50,hWidth,hHeight,image_dc,0,0,SRCCOPY);
        DeleteDC(image_dc);
        EndPaint(hWnd, &ps);
        break;
    case WM_DESTROY:
        DeleteObject(SelectObject(image_dc, hPen));
        PostQuitMessage(0);
        break;
    default:
        return DefWindowProc(hWnd, message, wParam, lParam);
    }
    return 0;
}