IsDefaultIgnorable returns `true` for codepoints with the Default_Ignorable property (as defined in unicode data DerivedCoreProperties.txt).

NewBuffer allocate a storage with default options.

NewFont constructs a new font object from the specified face.

ParseFeature parses one feature string (usually coming from a comma-separated list of font features).

ParseVariation parse the string representation of a variation of the form tag=value.

Flag indicating that special handling of the beginning of text paragraph can be applied to this buffer.

Text is set vertically from bottom to top.

Don't group cluster values.

Special value for language index indicating default or unsupported language.

Flag indicating that a dotted circle should not be inserted in the rendering of incorrect character sequences (such at <0905 093E>).

Flag indicating that special handling of the end of text paragraph can be applied to this buffer, similar to `Bot`.

Special setting for `Feature.End` to apply the feature from to the end of the buffer.

Special setting for `Feature.Start` to apply the feature from the start of the buffer.

In scripts that use elongation (Arabic, Mongolian, Syriac, etc.), this flag signifies that it is safe to insert a U+0640 TATWEEL character before this cluster for elongation.

Indicates that if input text is broken at the beginning of the cluster this glyph is part of, then both sides need to be re-shaped, as the result might be different.

Indicates that if input text is changed on one side of the beginning of the cluster this glyph is part of, then the shaping results for the other side might change.

Text is set horizontally from left to right.

Return cluster values grouped into monotone order.

Return cluster values grouped by graphemes into monotone order.

Special value for feature index indicating unsupported feature.

Special value for script index indicating unsupported script.

Flag indication that character with Default_Ignorable Unicode property should use the corresponding glyph from the font, instead of hiding them (done by replacing them with the space glyph and zeroing the advance width.) This flag takes precedence over `RemoveDefaultIgnorables`.

Flag indicating that the [GlyphSafeToInsertTatweel] glyph-flag should be produced by the shaper.

Flag indicating that the [GlyphUnsafeToConcat] glyph-flag should be produced by the shaper.

Flag indication that character with Default_Ignorable Unicode property should be removed from glyph string instead of hiding them (done by replacing them with the space glyph and zeroing the advance width.) `PreserveDefaultIgnorables` takes precedence over this flag.

Text is set horizontally from right to left.

Text is set vertically from top to bottom.

UniscribeBugCompatible alters shaping of indic and khmer scripts: - when `false`, it applies the recommended shaping choices - when `true`, Uniscribe behavior is reproduced.

Buffer is the main structure holding the input text segment and its properties before shaping, and output glyphs and their information after shaping.

Feature holds information about requested feature application.

Font is used internally as a wrapper around the provided Face.

GlyphExtents is the same as fonts.GlyphExtents but with int type.

GlyphInfo holds information about the glyphs and their relation to input text.

GlyphPosition holds the positions of the glyph in both horizontal and vertical directions.

SegmentProperties holds various text properties of a `Buffer`.

ClusterLevel allows selecting more fine-grained Cluster handling.

Direction is the text direction.

Position stores a position, scaled according to the `Font` scale parameters.

ShappingOptions controls some fine tunning of the shaping (see the constants).