public static FontModel Load(FontSource source)
{
var font = new FontModel();
var offsetTable = OffsetTable.Load(source);
if (offsetTable.SfntVersion == 0x10000)
{
font.Type = FontType.TrueType;
}
else if (offsetTable.SfntVersion == 0x4f54544f)
{
font.Type = FontType.OpenType;
}
else
{
throw new FontException($"Unknown sfntVersion: {offsetTable.SfntVersion:X4}");
}
var tableOffsets = new Dictionary <string, uint>(offsetTable.NumTables);
for (var i = 0; i < offsetTable.NumTables; i++)
{
var table = TableRecord.Load(source);
tableOffsets[table.Tag] = table.Offset;
}
LoadFontHeader(source, tableOffsets["head"], out var indexToLocFormat, out var unitsPerEm);
font.BaseScale = 1f / unitsPerEm;
font.UnitsPerEm = unitsPerEm;
var glyphCount = LoadGlyphCount(source, tableOffsets["maxp"]);
font._glyphs = new GlyphInfo[glyphCount];
var numberOfHMetrics = LoadNumberOfHMetrics(source, tableOffsets["hhea"]);
LoadHorizontalMetrics(font, source, tableOffsets["hmtx"], numberOfHMetrics, glyphCount);
font._glyphIndexMap = LoadCharacterToGlyphIndexMappingTable(source, tableOffsets["cmap"]);
if (tableOffsets.ContainsKey("loca"))
{
font._localOffsets = LoadIndexToLocation(source, tableOffsets["loca"], glyphCount, indexToLocFormat);
}
if (tableOffsets.ContainsKey("glyf"))
{
font._glyph = new GlyphTable(tableOffsets["glyf"]);
}
if (tableOffsets.ContainsKey("CFF"))
{
font._cff = CompactFontFormatTable.Load(tableOffsets["CFF"], source, font);
}
return(font);
}
public static GlyphContourInfoV2 ToVector2(this GlyphContourInfo g, FontModel model, FontSource source)
{
switch (model.Type)
{
case FontModel.FontType.TrueType:
return(FromTtfGlyph(g, model, source));
case FontModel.FontType.OpenType:
return(FromOtfGlyph(g, model, source));
default:
throw new InvalidEnumArgumentException(model.Type.ToString());
}
}
private static void LoadHorizontalMetrics(FontModel font, FontSource p, uint tableOffset, int numberOfHMetrics, int numGlyphs)
{
ushort advancedWidth = 0;
short leftSideBearing = 0;
p.Offset = tableOffset;
for (var i = 0; i < numGlyphs; i++)
{
if (i < numberOfHMetrics)
{
advancedWidth = p.ReadUShort();
leftSideBearing = p.ReadShort();
}
font._glyphs[i] = new GlyphInfo(advancedWidth, leftSideBearing);
}
}
private static GlyphContourInfoV2 FromOtfGlyph(GlyphContourInfo g, FontModel model, FontSource source)
{
var advancedWidth = g.BaseInfo.AdvancedWidth * model.BaseScale;
var leftSideBearing = g.BaseInfo.LeftSideBearing * model.BaseScale;
var contours = new List <List <ContourPoint> >();
List <ContourPoint> contour = null;
foreach (var cp in g.Path.Points)
{
if (cp.isContour)
{
contour = new List <ContourPoint>();
contours.Add(contour);
}
if (cp.isCurve)
{
contour.Add(new ContourPoint((short)cp.x, (short)cp.y, false));
}
else
{
contour.Add(new ContourPoint((short)cp.x, (short)cp.y, true));
}
}
foreach (var c in contours)
{
var first = c[0];
var last = c[c.Count - 1];
if (first.X == last.X && first.Y == last.Y)
{
c.RemoveAt(c.Count - 1);
}
}
return(new GlyphContourInfoV2(advancedWidth, leftSideBearing, ContourToVector(contours, model.BaseScale, false)));
}
private static GlyphContourInfoV2 FromTtfGlyph(GlyphContourInfo g, FontModel model, FontSource source)
{
var advancedWidth = g.BaseInfo.AdvancedWidth * model.BaseScale;
var leftSideBearing = g.BaseInfo.LeftSideBearing * model.BaseScale;
if (g.Header.NumberOfContours > 0)
{
var con = new List <List <ContourPoint> >();
var points = g.Header.GetGlyphPoints(source);
if (points == null || points.Length == 0)
{
throw new FontException("Cannot get points");
}
var list = new List <ContourPoint>();
con.Add(list);
for (var i = 0; i < points.Length; i++)
{
var point = points[i];
var contourPoint = new ContourPoint(point.X, point.Y, point.OnCurve);
list.Add(contourPoint);
if (point.IsEndPoint && i != points.Length - 1)
{
list = new List <ContourPoint>();
con.Add(list);
}
}
return(new GlyphContourInfoV2(advancedWidth, leftSideBearing, ContourToVector(con, model.BaseScale, true)));
}
else
{
// Composite Glyph
var components = g.Header.GetGlyphComponents(source);
var con = new List <List <ContourPoint> >();
foreach (var component in components)
{
var cg = model.GetGlyphFromGid(component.GlyphId, source);
if (cg.Header.NumberOfContours > 0)
{
var points = cg.Header.GetGlyphPoints(source);
if (points == null || points.Length == 0)
{
throw new FontException("Cannot get points");
}
if (component.MatchedPoints == null)
{
GlyphTable.GlyphHeader.GlyphComponent.TransformPoints(points, component);
}
else
{
// MatchedPoints are not supported.
break;
}
var list = new List <ContourPoint>();
con.Add(list);
for (var i = 0; i < points.Length; i++)
{
var point = points[i];
var contourPoint = new ContourPoint(point.X, point.Y, point.OnCurve);
list.Add(contourPoint);
if (point.IsEndPoint && i != points.Length - 1)
{
list = new List <ContourPoint>();
con.Add(list);
}
}
}
}
return(new GlyphContourInfoV2(advancedWidth, leftSideBearing, ContourToVector(con, model.BaseScale, true)));
}
}
