BuildAutomatic

FontFallbackSettings.BuildAutomatic method

Automatically builds the fallback settings by scanning available fonts.

public void BuildAutomatic()

Remarks

This method may produce non-optimal fallback settings. Fonts are checked by Unicode Character Range fields and not by the actual glyphs presence. Also Unicode ranges are checked individually and several ranges related to single language/script may use different fallback fonts.

Examples

Shows how to distribute fallback fonts across Unicode character code ranges.

Document doc = new Document();

FontSettings fontSettings = new FontSettings();
doc.FontSettings = fontSettings;
FontFallbackSettings fontFallbackSettings = fontSettings.FallbackSettings;

// Configure our font settings to source fonts only from the "MyFonts" folder.
FolderFontSource folderFontSource = new FolderFontSource(FontsDir, false);
fontSettings.SetFontsSources(new FontSourceBase[] {folderFontSource});

// Calling the "BuildAutomatic" method will generate a fallback scheme that
// distributes accessible fonts across as many Unicode character codes as possible.
// In our case, it only has access to the handful of fonts inside the "MyFonts" folder.
fontFallbackSettings.BuildAutomatic();
fontFallbackSettings.Save(ArtifactsDir + "FontSettings.FallbackSettingsCustom.BuildAutomatic.xml");

// We can also load a custom substitution scheme from a file like this.
// This scheme applies the "AllegroOpen" font across the "0000-00ff" Unicode blocks, the "AllegroOpen" font across "0100-024f",
// and the "M+ 2m" font in all other ranges that other fonts in the scheme do not cover.
fontFallbackSettings.Load(MyDir + "Custom font fallback settings.xml");

// Create a document builder and set its font to one that does not exist in any of our sources.
// Our font settings will invoke the fallback scheme for characters that we type using the unavailable font.
DocumentBuilder builder = new DocumentBuilder(doc);
builder.Font.Name = "Missing Font";

// Use the builder to print every Unicode character from 0x0021 to 0x052F,
// with descriptive lines dividing Unicode blocks we defined in our custom font fallback scheme.
for (int i = 0x0021; i < 0x0530; i++)
{
    switch (i)
    {
        case 0x0021:
            builder.Writeln(
                "\n\n0x0021 - 0x00FF: \nBasic Latin/Latin-1 Supplement Unicode blocks in \"AllegroOpen\" font:");
            break;
        case 0x0100:
            builder.Writeln(
                "\n\n0x0100 - 0x024F: \nLatin Extended A/B blocks, mostly in \"AllegroOpen\" font:");
            break;
        case 0x0250:
            builder.Writeln("\n\n0x0250 - 0x052F: \nIPA/Greek/Cyrillic blocks in \"M+ 2m\" font:");
            break;
    }

    builder.Write($"{Convert.ToChar(i)}");
}

doc.Save(ArtifactsDir + "FontSettings.FallbackSettingsCustom.pdf");

See Also

FontFallbackSettings.Load