void wxMacPrintPreview::DetermineScaling(void)
{
int screenWidth , screenHeight ;
wxDisplaySize( &screenWidth , &screenHeight ) ;
wxSize ppiScreen( 72 , 72 ) ;
wxSize ppiPrinter( 72 , 72 ) ;
// Note that with Leopard, screen dpi=72 is no longer a given
m_previewPrintout->SetPPIScreen( ppiScreen.x , ppiScreen.y ) ;
wxCoord w , h ;
wxCoord ww, hh;
wxRect paperRect;
// Get a device context for the currently selected printer
wxPrinterDC printerDC(m_printDialogData.GetPrintData());
if (printerDC.IsOk())
{
printerDC.GetSizeMM(&ww, &hh);
printerDC.GetSize( &w , &h ) ;
ppiPrinter = printerDC.GetPPI() ;
paperRect = printerDC.GetPaperRect();
m_isOk = true ;
}
else
{
// use some defaults
w = 8 * 72 ;
h = 11 * 72 ;
ww = (wxCoord) (w * 25.4 / ppiPrinter.x) ;
hh = (wxCoord) (h * 25.4 / ppiPrinter.y) ;
paperRect = wxRect(0, 0, w, h);
m_isOk = false ;
}
m_pageWidth = w;
m_pageHeight = h;
m_previewPrintout->SetPageSizePixels(w , h) ;
m_previewPrintout->SetPageSizeMM(ww, hh);
m_previewPrintout->SetPaperRectPixels(paperRect);
m_previewPrintout->SetPPIPrinter( ppiPrinter.x , ppiPrinter.y ) ;
m_previewScaleX = float(ppiScreen.x) / ppiPrinter.x;
m_previewScaleY = float(ppiScreen.y) / ppiPrinter.y;
}
void wxWindowsPrintPreview::DetermineScaling()
{
HDC dc = ::GetDC(NULL);
int screenWidth = ::GetDeviceCaps(dc, HORZSIZE);
int screenYRes = ::GetDeviceCaps(dc, VERTRES);
int logPPIScreenX = ::GetDeviceCaps(dc, LOGPIXELSX);
int logPPIScreenY = ::GetDeviceCaps(dc, LOGPIXELSY);
m_previewPrintout->SetPPIScreen(logPPIScreenX, logPPIScreenY);
::ReleaseDC(NULL, dc);
// Get a device context for the currently selected printer
wxPrinterDC printerDC(m_printDialogData.GetPrintData());
int printerWidth = 150;
int printerHeight wxDUMMY_INITIALIZE(250);
int printerXRes = 1500;
int printerYRes = 2500;
dc = GetHdcOf(printerDC);
if ( dc )
{
printerWidth = ::GetDeviceCaps(dc, HORZSIZE);
printerHeight = ::GetDeviceCaps(dc, VERTSIZE);
printerXRes = ::GetDeviceCaps(dc, HORZRES);
printerYRes = ::GetDeviceCaps(dc, VERTRES);
int logPPIPrinterX = ::GetDeviceCaps(dc, LOGPIXELSX);
int logPPIPrinterY = ::GetDeviceCaps(dc, LOGPIXELSY);
m_previewPrintout->SetPPIPrinter(logPPIPrinterX, logPPIPrinterY);
m_previewPrintout->SetPageSizeMM(printerWidth, printerHeight);
if (logPPIPrinterX == 0 || logPPIPrinterY == 0 || printerWidth == 0 || printerHeight == 0)
m_isOk = false;
}
else
m_isOk = false;
m_pageWidth = printerXRes;
m_pageHeight = printerYRes;
// At 100%, the page should look about page-size on the screen.
m_previewScale = (float)((float)screenWidth/(float)printerWidth);
m_previewScale = m_previewScale * (float)((float)screenYRes/(float)printerYRes);
}
bool wxWindowsPrintPreview::RenderPageIntoBitmap(wxBitmap& bmp, int pageNum)
{
// The preview, as implemented in wxPrintPreviewBase (and as used prior to
// wx3) is inexact: it uses screen DC, which has much lower resolution and
// has other properties different from printer DC, so the preview is not
// quite right.
//
// To make matters worse, if the application depends heavily on
// GetTextExtent() or does text layout itself, the output in preview and on
// paper can be very different. In particular, wxHtmlEasyPrinting is
// affected and the preview can be easily off by several pages.
//
// To fix this, we render the preview into high-resolution enhanced
// metafile with properties identical to the printer DC. This guarantees
// metrics correctness while still being fast.
// print the preview into a metafile:
wxPrinterDC printerDC(m_printDialogData.GetPrintData());
wxEnhMetaFileDC metaDC(printerDC,
wxEmptyString,
printerDC.GetSize().x, printerDC.GetSize().y);
if ( !RenderPageIntoDC(metaDC, pageNum) )
return false;
wxEnhMetaFile *metafile = metaDC.Close();
if ( !metafile )
return false;
// now render the metafile:
wxMemoryDC bmpDC;
bmpDC.SelectObject(bmp);
bmpDC.Clear();
wxRect outRect(0, 0, bmp.GetWidth(), bmp.GetHeight());
metafile->Play(&bmpDC, &outRect);
delete metafile;
// TODO: we should keep the metafile and reuse it when changing zoom level
return true;
}
void wxMacPrintPreview::DetermineScaling(void)
{
int screenWidth , screenHeight ;
wxDisplaySize( &screenWidth , &screenHeight ) ;
m_previewPrintout->SetPPIScreen( 72 , 72 ) ;
m_previewPrintout->SetPPIPrinter( 72 , 72 ) ;
m_previewPrintout->SetPageSizeMM( (int) (8.0 * 25.6), (int) (11.0 * 25.6) );
m_previewPrintout->SetPageSizePixels( 8 * 72 , 11 * 72 ) ;
m_pageWidth = 8 * 72 ;
m_pageHeight = 11 * 72 ;
m_previewScale = 1 ;
// Get a device context for the currently selected printer
wxPrinterDC printerDC(m_printDialogData.GetPrintData());
if (printerDC.Ok())
{
int x , y ;
wxCoord ww, hh;
printerDC.GetSizeMM(&ww, &hh);
printerDC.GetSize( &x , &y ) ;
m_previewPrintout->SetPageSizeMM((int)ww, (int)hh);
m_previewPrintout->SetPageSizePixels( x , y) ;
m_pageWidth = x ;
m_pageHeight = y ;
m_isOk = true ;
}
else
{
m_isOk = false ;
}
// At 100%, the page should look about page-size on the screen.
// m_previewScale = (float)((float)screenWidth/(float)printerWidth);
// m_previewScale = m_previewScale * (float)((float)screenXRes/(float)printerXRes);
m_previewScale = 1 ;
}
void wxWindowsPrintPreview::DetermineScaling()
{
ScreenHDC dc;
int logPPIScreenX = ::GetDeviceCaps(dc, LOGPIXELSX);
int logPPIScreenY = ::GetDeviceCaps(dc, LOGPIXELSY);
m_previewPrintout->SetPPIScreen(logPPIScreenX, logPPIScreenY);
// Get a device context for the currently selected printer
wxPrinterDC printerDC(m_printDialogData.GetPrintData());
int printerWidthMM;
int printerHeightMM;
int printerXRes;
int printerYRes;
int logPPIPrinterX;
int logPPIPrinterY;
wxRect paperRect;
if ( printerDC.IsOk() )
{
wxPrinterDCImpl *impl = (wxPrinterDCImpl*) printerDC.GetImpl();
HDC hdc = GetHdcOf(*impl);
printerWidthMM = ::GetDeviceCaps(hdc, HORZSIZE);
printerHeightMM = ::GetDeviceCaps(hdc, VERTSIZE);
printerXRes = ::GetDeviceCaps(hdc, HORZRES);
printerYRes = ::GetDeviceCaps(hdc, VERTRES);
logPPIPrinterX = ::GetDeviceCaps(hdc, LOGPIXELSX);
logPPIPrinterY = ::GetDeviceCaps(hdc, LOGPIXELSY);
paperRect = printerDC.GetPaperRect();
if ( logPPIPrinterX == 0 ||
logPPIPrinterY == 0 ||
printerWidthMM == 0 ||
printerHeightMM == 0 )
{
m_isOk = false;
}
}
else
{
// use some defaults
printerWidthMM = 150;
printerHeightMM = 250;
printerXRes = 1500;
printerYRes = 2500;
logPPIPrinterX = 600;
logPPIPrinterY = 600;
paperRect = wxRect(0, 0, printerXRes, printerYRes);
m_isOk = false;
}
m_pageWidth = printerXRes;
m_pageHeight = printerYRes;
m_previewPrintout->SetPageSizePixels(printerXRes, printerYRes);
m_previewPrintout->SetPageSizeMM(printerWidthMM, printerHeightMM);
m_previewPrintout->SetPaperRectPixels(paperRect);
m_previewPrintout->SetPPIPrinter(logPPIPrinterX, logPPIPrinterY);
// At 100%, the page should look about page-size on the screen.
m_previewScaleX = float(logPPIScreenX) / logPPIPrinterX;
m_previewScaleY = float(logPPIScreenY) / logPPIPrinterY;
}
bool wxWindowsPrintPreview::RenderPageIntoBitmapHQ(wxBitmap& bmp, int pageNum)
{
wxLogTrace("printing", "rendering HQ preview of page %i", pageNum);
wxPrinterDC printerDC(m_printDialogData.GetPrintData());
if ( !printerDC.IsOk() )
return false;
// compute scale factor
const float scaleX = float(bmp.GetWidth()) / float(m_pageWidth);
const float scaleY = float(bmp.GetHeight()) / float(m_pageHeight);
wxMemoryDC bmpDC;
bmpDC.SelectObject(bmp);
bmpDC.Clear();
const int initialStep = ComputeFragmentSize(printerDC.GetDepth(),
m_pageWidth, m_pageHeight);
wxRect todo(0, 0, m_pageWidth, initialStep); // rect to render
int nextFinalLine = 0; // first not-yet-rendered output line
while ( todo.y < m_pageHeight )
{
todo.SetBottom(wxMin(todo.GetBottom(), m_pageHeight - 1));
if ( !RenderPageFragment(scaleX, scaleY,
&nextFinalLine,
printerDC,
bmpDC,
todo,
pageNum) )
{
if ( todo.height < 20 )
{
// something is very wrong if we can't render even at this
// slow space, let's bail out and fall back to low quality
// preview
wxLogTrace("printing",
"it seems that HQ preview doesn't work at all");
return false;
}
// it's possible our memory calculation was off, or conditions
// changed, or there's not enough _bitmap_ resources; try if using
// smaller bitmap would help:
todo.height /= 2;
wxLogTrace("printing",
"preview of fragment failed, reducing height to %ipx",
todo.height);
continue; // retry at the same position again
}
// move to the next segment
todo.Offset(0, todo.height);
}
return true;
}
