public static void ReadGlyph(
DataReader reader, int glyphIndex, int recursionDepth,
BaseGlyph[] glyphTable, uint glyfOffset, uint glyfLength, uint *loca
)
{
// check if this glyph has already been loaded; this can happen
// if we're recursively loading subglyphs as part of a composite
if (glyphTable[glyphIndex] != null)
{
return;
}
// prevent bad font data from causing infinite recursion
if (recursionDepth > MaxRecursion)
{
throw new InvalidFontException("Bad font data; infinite composite recursion.");
}
// check if this glyph doesn't have any actual data
GlyphHeader header;
var offset = loca[glyphIndex];
if ((glyphIndex < glyphTable.Length - 1 && offset == loca[glyphIndex + 1]) || offset >= glyfLength)
{
// this is an empty glyph, so synthesize a header
header = default(GlyphHeader);
}
else
{
// seek to the right spot and load the header
reader.Seek(glyfOffset + loca[glyphIndex]);
header = new GlyphHeader {
ContourCount = reader.ReadInt16BE(),
MinX = reader.ReadInt16BE(),
MinY = reader.ReadInt16BE(),
MaxX = reader.ReadInt16BE(),
MaxY = reader.ReadInt16BE()
};
if (header.ContourCount < -1 || header.ContourCount > MaxContours)
{
throw new InvalidFontException("Invalid number of contours for glyph.");
}
}
if (header.ContourCount > 0)
{
// positive contours means a simple glyph
glyphTable[glyphIndex] = ReadSimpleGlyph(reader, header.ContourCount);
}
else if (header.ContourCount == -1)
{
// -1 means composite glyph
var composite = ReadCompositeGlyph(reader);
var subglyphs = composite.Subglyphs;
// read each subglyph recrusively
for (int i = 0; i < subglyphs.Length; i++)
{
ReadGlyph(reader, subglyphs[i].Index, recursionDepth + 1, glyphTable, glyfOffset, glyfLength, loca);
}
glyphTable[glyphIndex] = composite;
}
else
{
// no data, so synthesize an empty glyph
glyphTable[glyphIndex] = new SimpleGlyph {
Points = new Point[0],
ContourEndpoints = new int[0]
};
}
// save bounding box
var glyph = glyphTable[glyphIndex];
glyph.MinX = header.MinX;
glyph.MinY = header.MinY;
glyph.MaxX = header.MaxX;
glyph.MaxY = header.MaxY;
}
public static void ReadGlyph(
DataReader reader, int glyphIndex, int recursionDepth,
BaseGlyph[] glyphTable, uint glyfOffset, uint glyfLength, uint* loca
)
{
// check if this glyph has already been loaded; this can happen
// if we're recursively loading subglyphs as part of a composite
if (glyphTable[glyphIndex] != null)
return;
// prevent bad font data from causing infinite recursion
if (recursionDepth > MaxRecursion)
throw new InvalidFontException("Bad font data; infinite composite recursion.");
// check if this glyph doesn't have any actual data
GlyphHeader header;
var offset = loca[glyphIndex];
if ((glyphIndex < glyphTable.Length - 1 && offset == loca[glyphIndex + 1]) || offset >= glyfLength)
{
// this is an empty glyph, so synthesize a header
header = default(GlyphHeader);
}
else
{
// seek to the right spot and load the header
reader.Seek(glyfOffset + loca[glyphIndex]);
header = new GlyphHeader
{
ContourCount = reader.ReadInt16BE(),
MinX = reader.ReadInt16BE(),
MinY = reader.ReadInt16BE(),
MaxX = reader.ReadInt16BE(),
MaxY = reader.ReadInt16BE()
};
if (header.ContourCount < -1 || header.ContourCount > MaxContours)
throw new InvalidFontException("Invalid number of contours for glyph.");
}
if (header.ContourCount > 0)
{
// positive contours means a simple glyph
glyphTable[glyphIndex] = ReadSimpleGlyph(reader, header.ContourCount);
}
else if (header.ContourCount == -1)
{
// -1 means composite glyph
var composite = ReadCompositeGlyph(reader);
var subglyphs = composite.Subglyphs;
// read each subglyph recrusively
for (int i = 0; i < subglyphs.Length; i++)
ReadGlyph(reader, subglyphs[i].Index, recursionDepth + 1, glyphTable, glyfOffset, glyfLength, loca);
glyphTable[glyphIndex] = composite;
}
else
{
// no data, so synthesize an empty glyph
glyphTable[glyphIndex] = new SimpleGlyph
{
Points = new Point[0],
ContourEndpoints = new int[0]
};
}
// save bounding box
var glyph = glyphTable[glyphIndex];
glyph.MinX = header.MinX;
glyph.MinY = header.MinY;
glyph.MaxX = header.MaxX;
glyph.MaxY = header.MaxY;
}