/// <summary>
/// Returns a subclass of the PdfFont class that may be one of
/// PdfType0Font, PdfType1Font or PdfTrueTypeFont. The type of
/// subclass returned is determined by the type of the <i>font</i>
/// parameter.
/// </summary>
/// <param name="pdfFontID">The PDF font identifier, e.g. F15</param>
/// <param name="font">Underlying font object.</param>
/// <returns></returns>
public PdfFont MakeFont(string pdfFontID, Font font)
{
PdfFont pdfFont = null;
if (font is Base14Font)
{
// One of the standard base 14 fonts
Base14Font base14 = (Base14Font)font;
pdfFont = CreateBase14Font(pdfFontID, base14);
}
else
{
// Will load underlying font if proxy
IFontMetric realMetrics = GetFontMetrics(font);
if (realMetrics is Base14Font)
{
// A non-embeddable font that has been defaulted to a base 14 font
Base14Font base14 = (Base14Font)realMetrics;
pdfFont = CreateBase14Font(pdfFontID, base14);
}
else if (realMetrics is TrueTypeFont)
{
// TrueTypeFont restricted to the WinAnsiEncoding scheme
// that is linked instead of embedded in the PDF.
TrueTypeFont ttf = (TrueTypeFont)realMetrics;
pdfFont = CreateTrueTypeFont(pdfFontID, font, ttf);
}
else
{
// A character indexed font that may be subsetted.
CIDFont cid = (CIDFont)realMetrics;
pdfFont = CreateCIDFont(pdfFontID, font, cid);
}
}
// This should never happen, but it's worth checking
if (pdfFont == null)
{
throw new Exception("Unable to create Pdf font object for " + pdfFontID);
}
creator.AddObject(pdfFont);
return pdfFont;
}
/// <summary>
/// Loads the underlying font.
/// </summary>
private void LoadIfNecessary() {
if (!fontLoaded) {
switch (fontType) {
case FontType.Link:
realFont = new TrueTypeFont(properties);
break;
case FontType.Embed:
case FontType.Subset:
realFont = LoadCIDFont();
break;
default:
throw new Exception("Unknown font type: " + fontType.ToString());
}
fontLoaded = true;
}
}
private Font LoadCIDFont() {
switch (fontType) {
case FontType.Embed:
realFont = new Type2CIDFont(properties);
break;
case FontType.Subset:
realFont = new Type2CIDSubsetFont(properties);
break;
}
// Flag that indicates whether the CID font should be replaced by a
// base 14 font due to a license violation
bool replaceFont = false;
IFontDescriptor descriptor = realFont.Descriptor;
if (!descriptor.IsEmbeddable) {
FonetDriver.ActiveDriver.FireFonetWarning(
String.Format("Unable to embed font '{0}' because the license states embedding is not allowed. Will default to Helvetica.", realFont.FontName));
replaceFont = true;
}
// TODO: Do not permit subsetting if license does not allow it
if (realFont is Type2CIDSubsetFont && !descriptor.IsSubsettable) {
FonetDriver.ActiveDriver.FireFonetWarning(
String.Format("Unable to subset font '{0}' because the license states subsetting is not allowed.. Will default to Helvetica.", realFont.FontName));
replaceFont = true;
}
if (replaceFont) {
if (properties.IsBoldItalic) {
realFont = Base14Font.HelveticaBoldItalic;
}
else if (properties.IsBold) {
realFont = Base14Font.HelveticaBold;
}
else if (properties.IsItalic) {
realFont = Base14Font.HelveticaItalic;
}
else {
realFont = Base14Font.Helvetica;
}
}
return realFont;
}
/// <summary>
/// Creates a character indexed font from <i>cidFont</i>
/// </summary>
/// <remarks>
/// The <i>font</i> and <i>cidFont</i> will be different object
/// references since the <i>font</i> parameter will most likely
/// be a <see cref="ProxyFont"/>.
/// </remarks>
/// <param name="pdfFontID">The Pdf font identifier, e.g. F15</param>
/// <param name="font">Required to access the font descriptor.</param>
/// <param name="cidFont">The underlying CID font.</param>
/// <returns></returns>
private PdfFont CreateCIDFont(
string pdfFontID, Font font, CIDFont cidFont)
{
// The font descriptor is required to access licensing details are
// obtain the font program itself as a byte array
IFontDescriptor descriptor = font.Descriptor;
// A compressed stream that stores the font program
PdfFontFile fontFile = new PdfFontFile(
NextObjectId(), descriptor.FontData);
// Add indirect reference to FontFile object to descriptor
PdfFontDescriptor pdfDescriptor = MakeFontDescriptor(pdfFontID, cidFont);
pdfDescriptor.FontFile2 = fontFile;
PdfCIDSystemInfo pdfCidSystemInfo = new PdfCIDSystemInfo(
cidFont.Registry, cidFont.Ordering, cidFont.Supplement);
PdfCIDFont pdfCidFont = new PdfCIDFont(
NextObjectId(), PdfFontSubTypeEnum.CIDFontType2, font.FontName);
pdfCidFont.SystemInfo = pdfCidSystemInfo;
pdfCidFont.Descriptor = pdfDescriptor;
pdfCidFont.DefaultWidth = new PdfNumeric(cidFont.DefaultWidth);
pdfCidFont.Widths = cidFont.WArray;
// Create a ToUnicode CMap that maps characters codes (GIDs) to
// unicode values. Very important to ensure searching and copying
// from a PDF document works correctly.
PdfCMap pdfCMap = new PdfCMap(NextObjectId());
pdfCMap.AddFilter(new FlateFilter());
pdfCMap.SystemInfo = pdfCidSystemInfo;
pdfCMap.AddBfRanges(cidFont.CMapEntries);
// Create a PDF object to represent the CID font
PdfType0Font pdfFont = new PdfType0Font(
NextObjectId(), pdfFontID, font.FontName);
pdfFont.Encoding = new PdfName(cidFont.Encoding);
pdfFont.Descendant = pdfCidFont;
pdfFont.ToUnicode = pdfCMap;
// Add all the Pdf objects to the document. MakeFont will add the actual
// PdfFont object to the document.
creator.AddObject(pdfDescriptor);
creator.AddObject(pdfCidFont);
creator.AddObject(pdfCMap);
creator.AddObject(fontFile);
return pdfFont;
}
/// <remarks>
/// A ProxyFont must first be resolved before getting the
/// IFontMetircs implementation of the underlying font.
/// </remarks>
/// <param name="font"></param>
private IFontMetric GetFontMetrics(Font font)
{
if (font is ProxyFont)
{
return ((ProxyFont)font).RealFont;
}
else
{
return font;
}
}
/// <summary>
/// Creates an instance of the <see cref="PdfTrueTypeFont"/> class
/// that defaults the font encoding to WinAnsiEncoding.
/// </summary>
/// <param name="pdfFontID"></param>
/// <param name="font"></param>
/// <param name="ttf"></param>
/// <returns></returns>
private PdfTrueTypeFont CreateTrueTypeFont(
string pdfFontID, Font font, TrueTypeFont ttf)
{
PdfFontDescriptor pdfDescriptor = MakeFontDescriptor(pdfFontID, ttf);
PdfTrueTypeFont pdfFont = new PdfTrueTypeFont(
NextObjectId(), pdfFontID, font.FontName);
pdfFont.Encoding = new PdfName("WinAnsiEncoding");
pdfFont.Descriptor = pdfDescriptor;
pdfFont.FirstChar = new PdfNumeric(ttf.FirstChar);
pdfFont.LastChar = new PdfNumeric(ttf.LastChar);
pdfFont.Widths = ttf.Array;
creator.AddObject(pdfDescriptor);
return pdfFont;
}
