/// <summary>
/// Recursively converts the page tree into a flat array.
/// </summary>
PdfDictionary[] GetKids(PdfReference iref, PdfPage.InheritedValues values, PdfDictionary parent)
{
// TODO: inherit inheritable keys...
PdfDictionary kid = (PdfDictionary)iref.Value;
#if true
string type = kid.Elements.GetName(Keys.Type);
if (type == "/Page")
{
PdfPage.InheritValues(kid, values);
return(new PdfDictionary[] { kid });
}
if (string.IsNullOrEmpty(type))
{
// Type is required. If type is missing, assume it is "/Page" and hope it will work.
// TODO Implement a "Strict" mode in PDFsharp and don't do this in "Strict" mode.
PdfPage.InheritValues(kid, values);
return(new PdfDictionary[] { kid });
}
#else
if (kid.Elements.GetName(Keys.Type) == "/Page")
{
PdfPage.InheritValues(kid, values);
return(new PdfDictionary[] { kid });
}
#endif
Debug.Assert(kid.Elements.GetName(Keys.Type) == "/Pages");
PdfPage.InheritValues(kid, ref values);
List <PdfDictionary> list = new List <PdfDictionary>();
PdfArray kids = kid.Elements["/Kids"] as PdfArray;
if (kids == null)
{
PdfReference xref3 = kid.Elements["/Kids"] as PdfReference;
kids = xref3.Value as PdfArray;
}
foreach (PdfReference xref2 in kids)
{
list.AddRange(GetKids(xref2, values, kid));
}
int count = list.Count;
Debug.Assert(count == kid.Elements.GetInteger("/Count"));
return(list.ToArray());
}
/// <summary>
/// Replaces the page tree by a flat array of indirect references to the pages objects.
/// </summary>
internal void FlattenPageTree()
{
// Acrobat creates a balanced tree if the number of pages is rougly more than ten. This is
// not difficult but obviously also not necessary. I created a document with 50000 pages with
// PDF4NET and Acrobat opened it in less than 2 seconds.
//PdfReference xrefRoot = Document.Catalog.Elements[PdfCatalog.Keys.Pages] as PdfReference;
//PdfDictionary[] pages = GetKids(xrefRoot, null);
// Promote inheritable values down the page tree
PdfPage.InheritedValues values = new PdfPage.InheritedValues();
PdfPage.InheritValues(this, ref values);
PdfDictionary[] pages = GetKids(Reference, values, null);
// Replace /Pages in catalog by this object
// xrefRoot.Value = this;
PdfArray array = new PdfArray(Owner);
foreach (PdfDictionary page in pages)
{
// Fix the parent
page.Elements[PdfPage.Keys.Parent] = Reference;
array.Elements.Add(page.Reference);
}
Elements.SetName(Keys.Type, "/Pages");
#if true
// direct array
Elements.SetValue(Keys.Kids, array);
#else
// incdirect array
Document.xrefTable.Add(array);
Elements.SetValue(Keys.Kids, array.XRef);
#endif
Elements.SetInteger(Keys.Count, array.Elements.Count);
}
