Improve PDF/A-1b support in QPdfWriter

Add new enum QPrinter::PdfVersion to switch QPdfWriter
into PDF/A-1b mode. In that mode
    - meta data are embedded in XMP format
    - a color profile for sRGB is embedded and an OutputIntent defined
    - the ID key is added to the document trailer dictionary
    - a CIDSet entry is added to the font descriptor
    - transparency is removed from pens, brushes and images

Change-Id: Ia8a24d83609b239e716aefc1ba05f07320dbd290
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

1 files changed, 32 insertions, 1 deletions

diff --git a/src/printsupport/kernel/qprinter.cpp b/src/printsupport/kernel/qprinter.cpp
index 53bed87dfc..638187c614 100644
--- a/src/printsupport/kernel/qprinter.cpp
+++ b/src/printsupport/kernel/qprinter.cpp
@@ -147,7 +147,8 @@ void QPrinterPrivate::initEngines(QPrinter::OutputFormat format, const QPrinterI
         printEngine = ps->createNativePrintEngine(printerMode);
         paintEngine = ps->createPaintEngine(printEngine, printerMode);
     } else {
-        QPdfPrintEngine *pdfEngine = new QPdfPrintEngine(printerMode);
+        const auto pdfEngineVersion = (pdfVersion == QPrinter::PdfVersion_1_4 ? QPdfEngine::Version_1_4 : QPdfEngine::Version_A1b);
+        QPdfPrintEngine *pdfEngine = new QPdfPrintEngine(printerMode, pdfEngineVersion);
         paintEngine = pdfEngine;
         printEngine = pdfEngine;
     }
@@ -685,7 +686,37 @@ QPrinter::OutputFormat QPrinter::outputFormat() const
     return d->outputFormat;
 }
 
+/*!
+    \since 5.10
+
+    Sets the PDF version for this printer to \a version.
+
+    If \a version is the same value as currently set then no change will be made.
+*/
+void QPrinter::setPdfVersion(PdfVersion version)
+{
+    Q_D(QPrinter);
+
+    if (d->pdfVersion == version)
+        return;
+
+    d->pdfVersion = version;
 
+    if (d->outputFormat == QPrinter::PdfFormat) {
+        d->changeEngines(d->outputFormat, QPrinterInfo());
+    }
+}
+
+/*!
+    \since 5.10
+
+    Returns the PDF version for this printer. The default is \c PdfVersion_1_4.
+*/
+QPrinter::PdfVersion QPrinter::pdfVersion() const
+{
+    Q_D(const QPrinter);
+    return d->pdfVersion;
+}
 
 /*! \internal
 */