/// <summary>
/// Look up the font mapping data for a typeface.
/// </summary>
private TypefaceMap Lookup(Typeface key)
{
TypefaceMap typefaceMap = _sizeLimitedCache.Get(key);
if (typefaceMap == null)
{
typefaceMap = new TypefaceMap(
key.FontFamily,
key.FallbackFontFamily,
key.CanonicalStyle,
key.CanonicalWeight,
key.CanonicalStretch,
key.NullFont
);
_sizeLimitedCache.Add(
key,
typefaceMap,
false // is not permanent in the cache.
);
}
return(typefaceMap);
}
