/// <summary>
/// Set the primary font family.
/// </summary>
/// <param name="fontFamilyName">Font family name.</param>
/// <returns>True if the name is valid, otherwise false.</returns>
public bool SetPrimaryFontFamily(string fontFamilyName)
{
if (FontFamilyCacheItem.TryCreate(this.fontCollection, fontFamilyName, out var item))
{
this.ClearFontCache();
this.baseFontFamilyName = fontFamilyName;
this.fontFamilies.Add(item);
return(true);
}
return(false);
}
public static bool TryCreate(DWrite.FontCollection collection, string fontFamilyName, out FontFamilyCacheItem item)
{
if (collection.FindFamilyName(fontFamilyName, out var index))
{
var fontFamily = collection.GetFontFamily(index);
item = new FontFamilyCacheItem(fontFamily);
return(true);
}
else
{
item = null;
return(false);
}
}
/// <summary>
/// Get font face for specified codepoint, weight and style.
/// </summary>
/// <param name="codePoint">The code point.</param>
/// <param name="weight">The font weight.</param>
/// <param name="style">The font style.</param>
/// <returns>Selected font face.</returns>
public DWrite.FontFace GetFontFace(int codePoint, DWrite.FontWeight weight, DWrite.FontStyle style)
{
foreach (var f in this.fontFamilies)
{
var face = f.GetFontFace(codePoint, weight, style);
if (face != null)
{
return(face);
}
}
using (var source = new SingleCharTextSource(this.factory, codePoint))
{
this.systemFontFallback.MapCharacters(
source,
0,
1,
this.fontCollection,
this.baseFontFamilyName,
weight,
style,
DWrite.FontStretch.Normal,
out var mappedLength,
out var font,
out var scale);
if (font != null)
{
FontFamilyCacheItem.TryCreate(this.fontCollection, font.FontFamily.FamilyNames.GetString(0), out var familyCache);
this.fontFamilies.Add(familyCache);
font.Dispose();
var fontFace = familyCache.GetFontFace(codePoint, weight, style);
if (fontFace != null)
{
return(fontFace);
}
}
}
// OK we don't have the glyph for this codepoint in the fallbacks.
// Use primary font to show something like '?'.
return(this.fontFamilies[0].GetFontFace(weight, style));
}
