Struct fonts::FontGroup

pub struct FontGroup {
    descriptor: FontDescriptor,
    families: SmallVec<[FontGroupFamily; 8]>,
    last_matching_fallback: Option<FontRef>,
}

A FontGroup is a prioritised list of fonts for a given set of font styles. It is used by TextRun to decide which font to render a character with. If none of the fonts listed in the styles are suitable, a fallback font may be used.

Fields

descriptor: FontDescriptor

families: SmallVec<[FontGroupFamily; 8]>

last_matching_fallback: Option<FontRef>

Implementations

impl FontGroup

pub fn new(style: &FontStyleStruct, descriptor: FontDescriptor) -> FontGroup

pub fn find_by_codepoint<S: FontSource>( &mut self, font_context: &FontContext<S>, codepoint: char, next_codepoint: Option<char>, ) -> Option<FontRef>

Finds the first font, or else the first fallback font, which contains a glyph for codepoint. If no such font is found, returns the first available font or fallback font (which will cause a “glyph not found” character to be rendered). If no font at all can be found, returns None.

pub fn first<S: FontSource>( &mut self, font_context: &FontContext<S>, ) -> Option<FontRef>

Find the first available font in the group, or the first available fallback font.

fn find<S, TemplatePredicate, FontPredicate>( &mut self, font_context: &FontContext<S>, template_predicate: TemplatePredicate, font_predicate: FontPredicate, ) -> Option<FontRef>

where S: FontSource, TemplatePredicate: Fn(FontTemplateRef) -> bool, FontPredicate: Fn(&FontRef) -> bool,

Attempts to find a font which matches the given template_predicate and font_predicate. This method mutates because we may need to load new font data in the process of finding a suitable font.

fn find_fallback<S, TemplatePredicate, FontPredicate>( &mut self, font_context: &FontContext<S>, options: FallbackFontSelectionOptions, template_predicate: TemplatePredicate, font_predicate: FontPredicate, ) -> Option<FontRef>

where S: FontSource, TemplatePredicate: Fn(FontTemplateRef) -> bool, FontPredicate: Fn(&FontRef) -> bool,

Attempts to find a suitable fallback font which matches the given template_predicate and font_predicate. The default family (i.e. “serif”) will be tried first, followed by platform-specific family names. If a codepoint is provided, then its Unicode block may be used to refine the list of family names which will be tried.

Trait Implementations

impl Debug for FontGroup

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl MallocSizeOf for FontGroup

fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize

Measure the heap usage of all descendant heap-allocated structures, but not the space taken up by the value itself.