Struct FontContext

pub struct FontContext {
    system_font_service_proxy: Arc<SystemFontServiceProxy>,
    resource_threads: Mutex<CoreResourceThread>,
    compositor_api: Mutex<CrossProcessCompositorApi>,
    fonts: RwLock<HashMap<FontCacheKey, Option<FontRef>>>,
    resolved_font_groups: RwLock<HashMap<FontGroupCacheKey, FontGroupRef>>,
    web_fonts: CrossThreadFontStore,
    webrender_font_keys: RwLock<HashMap<FontIdentifier, FontKey>>,
    webrender_font_instance_keys: RwLock<HashMap<FontParameters, FontInstanceKey>>,
    font_data: RwLock<HashMap<FontIdentifier, FontData>>,
    have_removed_web_fonts: AtomicBool,
}

The FontContext represents the per-thread/thread state necessary for working with fonts. It is the public API used by the layout and paint code. It talks directly to the system font service where required.

Fields

system_font_service_proxy: Arc<SystemFontServiceProxy>

resource_threads: Mutex<CoreResourceThread>

compositor_api: Mutex<CrossProcessCompositorApi>

A sender that can send messages and receive replies from the compositor.

fonts: RwLock<HashMap<FontCacheKey, Option<FontRef>>>

The actual instances of fonts ie a FontTemplate combined with a size and other font properties, along with the font data and a platform font instance.

resolved_font_groups: RwLock<HashMap<FontGroupCacheKey, FontGroupRef>>

A caching map between the specification of a font in CSS style and resolved FontGroup which contains information about all fonts that can be selected with that style.

web_fonts: CrossThreadFontStore

webrender_font_keys: RwLock<HashMap<FontIdentifier, FontKey>>

A collection of WebRender FontKeys generated for the web fonts that this FontContext controls.

webrender_font_instance_keys: RwLock<HashMap<FontParameters, FontInstanceKey>>

A collection of WebRender FontInstanceKeys generated for the web fonts that this FontContext controls.

font_data: RwLock<HashMap<FontIdentifier, FontData>>

The data for each web font FontIdentifier. This data might be used by more than one FontTemplate as each identifier refers to a URL.

have_removed_web_fonts: AtomicBool

Implementations

impl FontContext

pub fn new( system_font_service_proxy: Arc<SystemFontServiceProxy>, compositor_api: CrossProcessCompositorApi, resource_threads: ResourceThreads, ) -> Self

pub fn web_fonts_still_loading(&self) -> usize

fn get_font_data(&self, identifier: &FontIdentifier) -> Option<FontData>

pub fn font_group( &self, style: ServoArc<FontStyleStruct>, ) -> Arc<RwLock<FontGroup>>

Returns a FontGroup representing fonts which can be used for layout, given the style. Font groups are cached, so subsequent calls with the same style will return a reference to an existing FontGroup.

pub fn font_group_with_size( &self, style: ServoArc<FontStyleStruct>, size: Au, ) -> Arc<RwLock<FontGroup>>

Like Self::font_group, but overriding the size found in the FontStyleStruct with the given size in pixels.

pub fn font( &self, font_template: FontTemplateRef, font_descriptor: &FontDescriptor, ) -> Option<FontRef>

Returns a font matching the parameters. Fonts are cached, so repeated calls will return a reference to the same underlying Font.

fn get_font_maybe_synthesizing_small_caps( &self, font_template: FontTemplateRef, font_descriptor: &FontDescriptor, synthesize_small_caps: bool, ) -> Option<FontRef>

fn matching_web_font_templates( &self, descriptor_to_match: &FontDescriptor, family_descriptor: &FontFamilyDescriptor, ) -> Option<Vec<FontTemplateRef>>

pub fn matching_templates( &self, descriptor_to_match: &FontDescriptor, family_descriptor: &FontFamilyDescriptor, ) -> Vec<FontTemplateRef>

Try to find matching templates in this FontContext, first looking in the list of web fonts and falling back to asking the super::SystemFontService for a matching system font.

fn create_font( &self, font_template: FontTemplateRef, font_descriptor: FontDescriptor, synthesized_small_caps: Option<FontRef>, ) -> Result<FontRef, &'static str>

Create a Font for use in layout calculations, from a FontTemplateData returned by the cache thread and a FontDescriptor which contains the styling parameters.

pub(crate) fn create_font_instance_key( &self, font: &Font, rendering_group_id: RenderingGroupId, ) -> FontInstanceKey

fn create_web_font_instance( &self, font_template: FontTemplateRef, pt_size: Au, flags: FontInstanceFlags, variations: Vec<FontVariation>, rendering_group_id: RenderingGroupId, ) -> FontInstanceKey

fn invalidate_font_groups_after_web_font_load(&self)

pub fn is_supported_web_font_source(source: &&Source) -> bool

impl FontContext

fn start_loading_one_web_font( self: &Arc<FontContext>, webview_id: Option<WebViewId>, source_list: &SourceList, css_font_face_descriptors: CSSFontFaceDescriptors, completion_handler: WebFontLoadInitiator, )

fn process_next_web_font_source( self: &Arc<FontContext>, state: WebFontDownloadState, )

Trait Implementations

impl MallocSizeOf for FontContext

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.