Struct Fonts

pub struct Fonts {
    pub fonts: FontsImpl,
    /* private fields */
}

The collection of fonts used by epaint.

Required in order to paint text. Create one and reuse. Cheap to clone.

Each Fonts comes with a font atlas textures that needs to be used when painting.

If you are using egui, use egui::Context::set_fonts and egui::Context::fonts.

You need to call Self::begin_pass and Self::font_image_delta once every frame.

Fields

fonts: FontsImpl

Implementations

impl Fonts

pub fn new( max_texture_side: usize, text_alpha_from_coverage: AlphaFromCoverage, definitions: FontDefinitions, ) -> Self

Create a new Fonts for text layout. This call is expensive, so only create one Fonts and then reuse it.

• max_texture_side: largest supported texture size (one side).

pub fn begin_pass( &mut self, max_texture_side: usize, text_alpha_from_coverage: AlphaFromCoverage, )

Call at the start of each frame with the latest known pixels_per_point, max_texture_side, and text_alpha_from_coverage.

Call after painting the previous frame, but before using Fonts for the new frame.

This function will react to changes in pixels_per_point, max_texture_side, and text_alpha_from_coverage, as well as notice when the font atlas is getting full, and handle that.

pub fn font_image_delta(&mut self) -> Option<ImageDelta>

Call at the end of each frame (before painting) to get the change to the font texture since last call.

pub fn max_texture_side(&self) -> usize

pub fn definitions(&self) -> &FontDefinitions

pub fn texture_atlas(&self) -> &TextureAtlas

The font atlas. Pass this to crate::Tessellator.

pub fn image(&self) -> ColorImage

The full font atlas image.

pub fn font_image_size(&self) -> [usize; 2]

Current size of the font image. Pass this to crate::Tessellator.

pub fn has_glyph(&mut self, font_id: &FontId, c: char) -> bool

Can we display this glyph?

pub fn has_glyphs(&mut self, font_id: &FontId, s: &str) -> bool

Can we display all the glyphs in this text?

pub fn num_galleys_in_cache(&self) -> usize

pub fn font_atlas_fill_ratio(&self) -> f32

How full is the font atlas?

This increases as new fonts and/or glyphs are used, but can also decrease in a call to Self::begin_pass.

pub fn with_pixels_per_point(&mut self, pixels_per_point: f32) -> FontsView<'_>

Returns a FontsView with the given pixels_per_point that can be used to do text layout.