pub trait FontExt: 'static {
// Required methods
fn describe(&self) -> Option<FontDescription>;
fn describe_with_absolute_size(&self) -> Option<FontDescription>;
fn find_shaper(&self, language: &Language, ch: u32) -> Option<EngineShape>;
fn get_coverage(&self, language: &Language) -> Option<Coverage>;
fn get_font_map(&self) -> Option<FontMap>;
fn get_glyph_extents(&self, glyph: Glyph) -> (Rectangle, Rectangle);
fn get_metrics(&self, language: Option<&Language>) -> Option<FontMetrics>;
}