dcsvg.cpp

wxGTK 是 wxWidgets 的 linux GTK+ (>2.2.3)版本。wxWidgets 是一个跨平台的 GUI 框架

    //radius
    double rx = w / 2 ;
    double ry = h / 2 ;
    // center
    double xc = x + rx ;
    double yc = y + ry ;

    double xs, ys, xe, ye ;
    xs = xc + rx * cos (DegToRad(sa)) ;
    xe = xc + rx * cos (DegToRad(ea)) ;
    ys = yc - ry * sin (DegToRad(sa)) ;
    ye = yc - ry * sin (DegToRad(ea)) ;

    ///now same as circle arc...

    double theta1 = atan2(ys-yc, xs-xc);
    double theta2 = atan2(ye-yc, xe-xc);

    int fArc  ;                  // flag for large or small arc 0 means less than 180 degrees
    if ( (theta2 - theta1) > 0 ) fArc = 1; else fArc = 0 ;

    int fSweep ;
    if ( fabs(theta2 - theta1) > M_PI) fSweep = 1; else fSweep = 0 ;

    s.Printf ( wxT("<path d=\"M%d %d A%d %d 0.0 %d %d  %d %d L %d %d z "),
        int(xs), int(ys), int(rx), int(ry),
        fArc, fSweep, int(xe), int(ye), int(xc), int(yc)  );


    s = s + wxT(" \" /> ") + newline ;

    if (m_OK)
    {
        write(s);
    }

    wxASSERT_MSG(!wxSVG_DEBUG, wxT("wxSVGFileDC::DoDrawEllipticArc Call executed")) ;
}


void wxSVGFileDC::DoGetTextExtent(const wxString& string, wxCoord *w, wxCoord *h, wxCoord *descent , wxCoord *externalLeading , wxFont *font) const

{
    wxScreenDC sDC ;

    sDC.SetFont (m_font);
    if ( font != NULL ) sDC.SetFont ( *font );
    sDC.GetTextExtent(string, w,  h, descent, externalLeading );
    wxASSERT_MSG(!wxSVG_DEBUG, wxT("wxSVGFileDC::GetTextExtent Call executed")) ;
}


wxCoord wxSVGFileDC::GetCharHeight() const

{
    wxScreenDC sDC ;
    sDC.SetFont (m_font);

    wxASSERT_MSG(!wxSVG_DEBUG, wxT("wxSVGFileDC::GetCharHeight Call executing")) ;
    return ( sDC.GetCharHeight() );

}


wxCoord wxSVGFileDC::GetCharWidth() const
{
    wxScreenDC sDC ;
    sDC.SetFont (m_font);

    wxASSERT_MSG(!wxSVG_DEBUG, wxT("wxSVGFileDC::GetCharWidth Call executing")) ;
    return ( sDC.GetCharWidth() ) ;

}


/// Set Functions /////////////////////////////////////////////////////////////////
void wxSVGFileDC::SetBackground( const wxBrush &brush )
{

    m_backgroundBrush = brush;
    return;
}


void wxSVGFileDC::SetBackgroundMode( int mode )
{
    m_backgroundMode = mode;
    return;
}


void wxSVGFileDC::SetBrush(const wxBrush& brush)

{
    m_brush = brush ;

    m_graphics_changed = TRUE ;
    wxASSERT_MSG(!wxSVG_DEBUG, wxT("wxSVGFileDC::SetBrush Call executed")) ;
}


void wxSVGFileDC::SetPen(const wxPen& pen)
{
    // width, color, ends, joins : currently implemented
    // dashes, stipple :  not implemented
    m_pen = pen ;

    m_graphics_changed = TRUE ;
    wxASSERT_MSG(!wxSVG_DEBUG, wxT("wxSVGFileDC::SetPen Call executed")) ;
}

void wxSVGFileDC::NewGraphics ()
{

    int w = m_pen.GetWidth ();
    wxColour c = m_pen.GetColour () ;

    wxString s, sBrush, sPenCap, sPenJoin, sPenStyle, sLast, sWarn;

    sBrush = wxT("</g>\n<g style=\"") + wxBrushString ( m_brush.GetColour (), m_brush.GetStyle () )
             + wxT("  stroke:#") + wxColStr (c) + wxT("; ") ;

    switch ( m_pen.GetCap () )
    {
        case  wxCAP_PROJECTING :
            sPenCap = wxT("stroke-linecap:square; ") ;
            break ;
        case  wxCAP_BUTT :
            sPenCap = wxT("stroke-linecap:butt; ") ;
            break ;
        case    wxCAP_ROUND :
        default :
            sPenCap = wxT("stroke-linecap:round; ") ;
    };
    switch ( m_pen.GetJoin () )
    {
        case  wxJOIN_BEVEL :
            sPenJoin = wxT("stroke-linejoin:bevel; ") ;
            break ;
        case  wxJOIN_MITER :
            sPenJoin = wxT("stroke-linejoin:miter; ") ;
            break ;
        case    wxJOIN_ROUND :
        default :
            sPenJoin = wxT("stroke-linejoin:round; ") ;
    };

    switch ( m_pen.GetStyle () )
    {
        case  wxSOLID :
            sPenStyle = wxT("stroke-opacity:1.0; stroke-opacity:1.0; ") ;
            break ;
        case  wxTRANSPARENT :
            sPenStyle = wxT("stroke-opacity:0.0; stroke-opacity:0.0; ") ;
            break ;
        default :
            wxASSERT_MSG(FALSE, wxT("wxSVGFileDC::SetPen Call called to set a Style which is not available")) ;
            sWarn = sWarn + wxT("<!--- wxSVGFileDC::SetPen Call called to set a Style which is not available --> \n") ;
    }

    sLast.Printf (   wxT("stroke-width:%d\" \n   transform=\"translate(%.2g %.2g) scale(%.2g %.2g)\">"),
                  w, m_OriginX, m_OriginY, m_scaleX, m_scaleY  );

    s = sBrush + sPenCap + sPenJoin + sPenStyle + sLast + newline + sWarn;
    write(s);
    m_graphics_changed = FALSE ;
    wxASSERT_MSG(!wxSVG_DEBUG, wxT("wxSVGFileDC::NewGraphics Call executed")) ;
}


void wxSVGFileDC::SetFont(const wxFont& font)

{
    m_font = font ;

    wxASSERT_MSG(!wxSVG_DEBUG, wxT("wxSVGFileDC::SetFont Call executed")) ;
}


void wxSVGFileDC::ComputeScaleAndOrigin()
{
    m_scaleX = m_logicalScaleX * m_userScaleX;
    m_scaleY = m_logicalScaleY * m_userScaleY;
    m_OriginX = m_logicalOriginX * m_logicalScaleX + m_deviceOriginX ;
    m_OriginY = m_logicalOriginY * m_logicalScaleY + m_deviceOriginY ;
    m_graphics_changed = TRUE;
}


int wxSVGFileDC::GetMapMode()
{
    return m_mappingMode ;
}


void wxSVGFileDC::SetMapMode( int mode )
{
    switch (mode)
    {
        case wxMM_TWIPS:
            SetLogicalScale( twips2mm*m_mm_to_pix_x, twips2mm*m_mm_to_pix_y );
            break;
        case wxMM_POINTS:
            SetLogicalScale( pt2mm*m_mm_to_pix_x, pt2mm*m_mm_to_pix_y );
            break;
        case wxMM_METRIC:
            SetLogicalScale( m_mm_to_pix_x, m_mm_to_pix_y );
            break;
        case wxMM_LOMETRIC:
            SetLogicalScale( m_mm_to_pix_x/10.0, m_mm_to_pix_y/10.0 );
            break;
        default:
        case wxMM_TEXT:
            SetLogicalScale( 1.0, 1.0 );
            break;
    }
    m_mappingMode = mode;

    /*  we don't do this mega optimisation
        if (mode != wxMM_TEXT)
        {
            m_needComputeScaleX = TRUE;
            m_needComputeScaleY = TRUE;
        }
    */
}


void wxSVGFileDC::GetUserScale(double *x, double *y) const
{
    *x = m_userScaleX ;
    *y = m_userScaleY ;
}


void wxSVGFileDC::SetUserScale( double x, double y )
{
    // allow negative ? -> no
    m_userScaleX = x;
    m_userScaleY = y;
    ComputeScaleAndOrigin();
}


void wxSVGFileDC::SetLogicalScale( double x, double y )
{
    // allow negative ?
    m_logicalScaleX = x;
    m_logicalScaleY = y;
    ComputeScaleAndOrigin();
}


void wxSVGFileDC::SetLogicalOrigin( wxCoord x, wxCoord y )
{
    // is this still correct ?
    m_logicalOriginX = x * m_signX;
    m_logicalOriginY = y * m_signY;
    ComputeScaleAndOrigin();
}


void wxSVGFileDC::SetDeviceOrigin( wxCoord x, wxCoord y )
{
    // only wxPostScripDC has m_signX = -1,
    m_deviceOriginX = x;
    m_deviceOriginY = y;
    ComputeScaleAndOrigin();
}


void wxSVGFileDC::SetAxisOrientation( bool xLeftRight, bool yBottomUp )
{
    // only wxPostScripDC has m_signX = -1,
    m_signX = (xLeftRight ?  1 : -1);
    m_signY = (yBottomUp  ? -1 :  1);
    ComputeScaleAndOrigin();
}


// export a bitmap as a raster image in png
bool wxSVGFileDC::DoBlit(wxCoord xdest, wxCoord ydest, wxCoord width, wxCoord height,
                         wxDC* source, wxCoord xsrc, wxCoord ysrc,
                         int logicalFunc /*= wxCOPY*/, bool useMask /*= FALSE*/,
                         wxCoord /*xsrcMask = -1*/, wxCoord /*ysrcMask = -1*/)
{
    if (logicalFunc != wxCOPY)
    {
        wxASSERT_MSG(FALSE, wxT("wxSVGFileDC::DoBlit Call requested nonCopy mode; this is not possible")) ;
        return FALSE ;
    }
    if (useMask != FALSE)
    {
        wxASSERT_MSG(FALSE, wxT("wxSVGFileDC::DoBlit Call requested False mask ; this is not possible")) ;
        return FALSE ;
    }
    wxBitmap myBitmap (width, height) ;
    wxMemoryDC memDC;
    memDC.SelectObject( myBitmap );
    memDC.Blit(0, 0, width, height, source, xsrc, ysrc);
    memDC.SelectObject( wxNullBitmap );
    DoDrawBitmap(myBitmap, xdest, ydest);
    wxASSERT_MSG(!wxSVG_DEBUG, wxT("wxSVGFileDC::DoBlit Call executed")) ;
    return FALSE ;
}


void wxSVGFileDC::DoDrawIcon(const class wxIcon & myIcon, wxCoord x, wxCoord y)
{
    wxBitmap myBitmap (myIcon.GetWidth(), myIcon.GetHeight() ) ;
    wxMemoryDC memDC;
    memDC.SelectObject( myBitmap );
    memDC.DrawIcon(myIcon,0,0);
    memDC.SelectObject( wxNullBitmap );
    DoDrawBitmap(myBitmap, x, y);
    wxASSERT_MSG(!wxSVG_DEBUG, wxT("wxSVGFileDC::DoDrawIcon Call executed")) ;
    return ;
}



void wxSVGFileDC::DoDrawBitmap(const class wxBitmap & bmp, wxCoord x, wxCoord y , bool  WXUNUSED(bTransparent) /*=0*/ )
{
    if (m_graphics_changed) NewGraphics ();

    wxString sTmp, s, sPNG ;
    wxImage::AddHandler(new wxPNGHandler);

// create suitable file name
    sTmp.Printf ( wxT("_image%d.png"), m_sub_images);
    sPNG = m_filename.BeforeLast(wxT('.')) + sTmp;
    while (wxFile::Exists(sPNG) )
    {
        m_sub_images ++ ;
        sTmp.Printf ( wxT("_image%d.png"), m_sub_images);
        sPNG = m_filename.BeforeLast(wxT('.')) + sTmp;
    }

//create copy of bitmap (wxGTK doesn't like saving a constant bitmap)
    wxBitmap myBitmap = bmp ;
//save it
    bool bPNG_OK = myBitmap.SaveFile(sPNG,wxBITMAP_TYPE_PNG);

// refrence the bitmap from the SVG doc
    int w = myBitmap.GetWidth();
    int h = myBitmap.GetHeight();
    sTmp.Printf ( wxT(" <image x=\"%d\" y=\"%d\" width=\"%dpx\" height=\"%dpx\" "), x,y,w,h );
    s = s + sTmp ;
    sTmp.Printf ( wxT(" xlink:href=\"%s\"> \n"), sPNG.c_str() );
    s = s + sTmp + wxT("<title>Image from wxSVG</title>  </image>") + newline;

    if (m_OK && bPNG_OK)
    {
        write(s);
    }
    m_OK = m_outfile->Ok () && bPNG_OK;
    wxASSERT_MSG(!wxSVG_DEBUG, wxT("wxSVGFileDC::DoDrawBitmap Call executed")) ;

    return  ;
}


// ---------------------------------------------------------------------------
// coordinates transformations
// ---------------------------------------------------------------------------

wxCoord wxSVGFileDC::DeviceToLogicalX(wxCoord x) const
{
    return XDEV2LOG(x);
}


wxCoord wxSVGFileDC::DeviceToLogicalY(wxCoord y) const
{
    return YDEV2LOG(y);
}


wxCoord wxSVGFileDC::DeviceToLogicalXRel(wxCoord x) const
{
    return XDEV2LOGREL(x);
}


wxCoord wxSVGFileDC::DeviceToLogicalYRel(wxCoord y) const
{
    return YDEV2LOGREL(y);
}


wxCoord wxSVGFileDC::LogicalToDeviceX(wxCoord x) const
{
    return XLOG2DEV(x);
}


wxCoord wxSVGFileDC::LogicalToDeviceY(wxCoord y) const
{
    return YLOG2DEV(y);
}


wxCoord wxSVGFileDC::LogicalToDeviceXRel(wxCoord x) const
{
    return XLOG2DEVREL(x);
}


wxCoord wxSVGFileDC::LogicalToDeviceYRel(wxCoord y) const
{
    return YLOG2DEVREL(y);
}

void wxSVGFileDC::write(const wxString &s)
{
    const wxWX2MBbuf buf = s.mb_str(wxConvUTF8);
    m_outfile->Write(buf, strlen((const char *)buf));
    m_OK = m_outfile->Ok();
}

#ifdef __BORLANDC__
#pragma warn .rch
#pragma warn .ccc
#endif