double LIB_EDIT_FRAME::BestZoom()
{
    /* Please, note: wxMSW before version 2.9 seems have
     * problems with zoom values < 1 ( i.e. userscale > 1) and needs to be patched:
     * edit file <wxWidgets>/src/msw/dc.cpp
     * search for line static const int VIEWPORT_EXTENT = 1000;
     * and replace by static const int VIEWPORT_EXTENT = 10000;
     */
    int      dx, dy;

    LIB_PART*      part = GetCurPart();

    if( part )
    {
        EDA_RECT boundingBox = part->GetBoundingBox( m_unit, m_convert );

        dx = boundingBox.GetWidth();
        dy = boundingBox.GetHeight();
        SetScrollCenterPosition( wxPoint( 0, 0 ) );
    }
    else
    {
        const PAGE_INFO& pageInfo = GetScreen()->GetPageSettings();

        dx = pageInfo.GetSizeIU().x;
        dy = pageInfo.GetSizeIU().y;

        SetScrollCenterPosition( wxPoint( 0, 0 ) );
    }

    wxSize size = m_canvas->GetClientSize();

    // Reserve a 10% margin around component bounding box.
    double margin_scale_factor = 0.8;
    double zx =(double) dx / ( margin_scale_factor * (double)size.x );
    double zy = (double) dy / ( margin_scale_factor * (double)size.y );

    double bestzoom = std::max( zx, zy );

    // keep it >= minimal existing zoom (can happen for very small components
    // for instance when starting a new component
    if( bestzoom  < GetScreen()->m_ZoomList[0] )
        bestzoom  = GetScreen()->m_ZoomList[0];

    return bestzoom;
}
double LIB_VIEW_FRAME::BestZoom()
{
    /* Please, note: wxMSW before version 2.9 seems have
     * problems with zoom values < 1 ( i.e. userscale > 1) and needs to be patched:
     * edit file <wxWidgets>/src/msw/dc.cpp
     * search for line static const int VIEWPORT_EXTENT = 1000;
     * and replace by static const int VIEWPORT_EXTENT = 10000;
     */

    LIB_PART*   part = NULL;
    double      bestzoom = 16.0;      // default value for bestzoom
    PART_LIB*   lib = Prj().SchLibs()->FindLibrary( m_libraryName );

    if( lib  )
        part = lib->FindPart( m_entryName );

    if( !part )
    {
        SetScrollCenterPosition( wxPoint( 0, 0 ) );
        return bestzoom;
    }

    wxSize size = m_canvas->GetClientSize();

    EDA_RECT boundingBox = part->GetBoundingBox( m_unit, m_convert );

    // Reserve a 10% margin around component bounding box.
    double margin_scale_factor = 0.8;
    double zx =(double) boundingBox.GetWidth() /
               ( margin_scale_factor * (double)size.x );
    double zy = (double) boundingBox.GetHeight() /
                ( margin_scale_factor * (double)size.y);

    // Calculates the best zoom
    bestzoom = std::max( zx, zy );

    // keep it >= minimal existing zoom (can happen for very small components
    // like small power symbols
    if( bestzoom  < GetScreen()->m_ZoomList[0] )
        bestzoom  = GetScreen()->m_ZoomList[0];

    SetScrollCenterPosition( boundingBox.Centre() );

    return bestzoom;
}
void LIB_EDIT_FRAME::OnPlotCurrentComponent( wxCommandEvent& event )
{
    wxString   fullFileName;
    wxString   file_ext;
    wxString   mask;

    LIB_PART*      part = GetCurPart();

    if( !part )
    {
        wxMessageBox( _( "No component" ) );
        return;
    }

    switch( event.GetId() )
    {
    case ID_LIBEDIT_GEN_PNG_FILE:
        {
            bool       fmt_is_jpeg = false; // could be selectable later. so keep this option.

            file_ext = fmt_is_jpeg ? wxT( "jpg" ) : wxT( "png" );
            mask     = wxT( "*." ) + file_ext;
            wxFileName fn( part->GetName() );
            fn.SetExt( file_ext );

            wxString pro_dir = wxPathOnly( Prj().GetProjectFullName() );

            fullFileName = EDA_FILE_SELECTOR( _( "Filename:" ), pro_dir,
                                             fn.GetFullName(), file_ext, mask, this,
                                             wxFD_SAVE, true );

            if( fullFileName.IsEmpty() )
                return;

            // calling wxYield is mandatory under Linux, after closing the file selector dialog
            // to refresh the screen before creating the PNG or JPEG image from screen
            wxYield();
            CreatePNGorJPEGFile( fullFileName, fmt_is_jpeg );
        }
        break;

    case ID_LIBEDIT_GEN_SVG_FILE:
        {
            file_ext = wxT( "svg" );
            mask     = wxT( "*." ) + file_ext;
            wxFileName fn( part->GetName() );
            fn.SetExt( file_ext );

            wxString pro_dir = wxPathOnly( Prj().GetProjectFullName() );

            fullFileName = EDA_FILE_SELECTOR( _( "Filename:" ), pro_dir,
                                              fn.GetFullName(), file_ext, mask, this,
                                              wxFD_SAVE, true );

            if( fullFileName.IsEmpty() )
                return;

            PAGE_INFO pageSave = GetScreen()->GetPageSettings();
            PAGE_INFO pageTemp = pageSave;

            wxSize componentSize = part->GetBoundingBox( m_unit, m_convert ).GetSize();

            // Add a small margin to the plot bounding box
            pageTemp.SetWidthMils(  int( componentSize.x * 1.2 ) );
            pageTemp.SetHeightMils( int( componentSize.y * 1.2 ) );

            GetScreen()->SetPageSettings( pageTemp );
            SVG_PlotComponent( fullFileName );
            GetScreen()->SetPageSettings( pageSave );
        }
        break;
    }
}