/// <summary>
/// Adds a new page to the PDF and creates the needed PDF objects.
/// </summary>
public void AddPage()
{
currentContentStream = CreateContentStream(PDFStream.Filter.None);
pageContentStreams.Add(currentContentStream);
currentPageDictionary = CreateIndirectDictionary();
currentPageDictionary.Put("Type", new PDFName("Page"));
currentPageDictionary.Put("Parent", pagesDictionary);
currentPageDictionary.Put("Contents", currentContentStream);
currentPageDictionary.Put("MediaBox", mediaBox);
currentPageDictionary.Put("Resources", _commonResources);
pageDictionaries.Add(currentPageDictionary);
pageKidsArray.Array.Add(currentPageDictionary);
}
public PDFCreator(string pdfFileName)
{
this.pdfFileName = pdfFileName;
pageKidsArray = CreateIndirectArray();
mediaBox = new PDFArray(PDFObject.DirectObject,
0.0, 0.0, 595.2756, 841.8898); // A4
pagesDictionary = CreateIndirectDictionary();
pagesDictionary.Put("Type", new PDFName("Pages"));
pagesDictionary.Put("Kids", pageKidsArray);
//pagesDictionary.Put("Resources", ); // all PDF pages would inherit these resources
PDFDictionary catalog = CreateIndirectDictionary();
catalog.Put("Type", new PDFName("Catalog"));
catalog.Put("Pages", pagesDictionary);
PDFDictionary infoDictionary = CreateIndirectDictionary();
infoDictionary.Put("Creator", new PDFString("Menu Master"));
infoDictionary.Put("CreationDate", PDFString.GetDateString());
PDFString fileIdString = PDFString.CreateFileIDString();
trailerDictionary = new PDFDictionary(PDFObject.DirectObject);
trailerDictionary.Put("Root", catalog);
trailerDictionary.Put("ID", new PDFArray(PDFObject.DirectObject, fileIdString, fileIdString));
trailerDictionary.Put("Info", infoDictionary);
_commonResources = CreateIndirectDictionary();
_commonFontResources = CreateIndirectDictionary();
_commonResources.Put("Font", _commonFontResources);
// PDF must have at least one page
AddPage();
}
/// <summary>
/// Finishes PDF creation and writes all PDF objects to the specified file.
/// This must be called as the final step when creating a PDF.
/// </summary>
public void Finish()
{
// Set actual page count
pagesDictionary.Put("Count", new PDFInt(pageDictionaries.Count));
// Set actual number of objects
trailerDictionary.Put("Size", new PDFInt(indirectObjects.Count + 1));
foreach (PDFFont font in _fontMapping.Values)
{
font.CreatePDFData(this);
_commonFontResources.Put($"F{font.ResourceKeyId}", font.GetFontDictionary());
}
WritePDFFile();
}
private void AddFontMetrics(PDFDictionary fontDescriptor, GlyphTypeface glyphTypeface,
byte[] subsetData)
{
// We must parse the 'head' table of the font file to get FontBBox.
using (Stream stream = new MemoryStream(subsetData))
{
ReadSfntVersion(stream);
int numTables = ReadInt16(stream) & 0xFFFF;
ReadInt16(stream); // searchRange
ReadInt16(stream); // entrySelector
ReadInt16(stream); // rangeShift
int headTableOffset = -1;
for (int i = 0; i < numTables; i++)
{
int tag = ReadInt32(stream);
ReadInt32(stream); // checksum
int offset = ReadInt32(stream);
ReadInt32(stream); // length
switch (tag)
{
case 0x68656164: // 'head'
headTableOffset = offset;
break;
}
}
if (headTableOffset == -1)
{
throw new IOException("Cannot find 'head' table in font");
}
stream.Seek(headTableOffset + 12, SeekOrigin.Begin);
int magic = ReadInt32(stream);
if (magic != 0x5F0F3CF5)
{
throw new IOException("Invalid magic code in 'head' table");
}
ReadInt16(stream); // flags
int unitsPerEm = ReadInt16(stream) & 0xFFFF;
stream.Seek(2 * 8, SeekOrigin.Current); // Skip creation and modification dates
int left = ReadInt16(stream);
int bottom = ReadInt16(stream);
int right = ReadInt16(stream);
int top = ReadInt16(stream);
// Convert to font size 1000
left = (int)Math.Floor(1000.0 * left / unitsPerEm);
bottom = (int)Math.Floor(1000.0 * bottom / unitsPerEm);
right = (int)Math.Ceiling(1000.0 * right / unitsPerEm);
top = (int)Math.Ceiling(1000.0 * top / unitsPerEm);
PDFArray fontBBox = new PDFArray(PDFObject.DirectObject);
fontBBox.Array.Add(new PDFInt(left));
fontBBox.Array.Add(new PDFInt(bottom));
fontBBox.Array.Add(new PDFInt(right));
fontBBox.Array.Add(new PDFInt(top));
fontDescriptor.Put("FontBBox", fontBBox);
fontDescriptor.Put("Descent", new PDFInt(bottom));
fontDescriptor.Put("Ascent", new PDFInt((int)(1000 * glyphTypeface.Baseline)));
fontDescriptor.Put("CapHeight", new PDFInt((int)(1000 * glyphTypeface.CapsHeight)));
fontDescriptor.Put("StemV", new PDFInt(90)); // just a guess
FontStyle style = _typeface.Style;
double italicAngle =
(style == FontStyles.Italic || style == FontStyles.Oblique) ? -12.0 : 0.0; // just a guess
fontDescriptor.Put("ItalicAngle", new PDFReal(italicAngle));
}
}