Struct gfx_glyph::GlyphBrush

pub struct GlyphBrush<'font, R: Resources, F: Factory<R>, H = DefaultSectionHasher> { /* fields omitted */ }

Object allowing glyph drawing, containing cache state. Manages glyph positioning cacheing, glyph draw caching & efficient GPU texture cache updating and re-sizing on demand.

Build using a GlyphBrushBuilder.

Example

use gfx_glyph::Section;

let section = Section {
    text: "Hello gfx_glyph",
    ..Section::default()
};

glyph_brush.queue(section);
glyph_brush.queue(some_other_section);

glyph_brush.use_queue().draw(&mut gfx_encoder, &gfx_color)?;

Caching behaviour

Calls to GlyphBrush::queue, GlyphBrush::pixel_bounds, GlyphBrush::glyphs calculate the positioned glyphs for a section. This is cached so future calls to any of the methods for the same section are much cheaper. In the case of GlyphBrush::queue the calculations will also be used for actual drawing.

The cache for a section will be cleared after a .use_queue().draw(..) call when that section has not been used since the previous draw call.

Methods

impl<'font, R: Resources, F: Factory<R>, H: BuildHasher> GlyphBrush<'font, R, F, H>

pub fn queue<'a, S>(&mut self, section: S) where
    S: Into<Cow<'a, VariedSection<'a>>>, 

Queues a section/layout to be drawn by the next call of .use_queue().draw(..). Can be called multiple times to queue multiple sections for drawing.

Benefits from caching, see caching behaviour.

pub fn use_queue(&mut self) -> DrawBuilder<'_, 'font, R, F, H, ()>

Returns a DrawBuilder allowing the queued glyphs to be drawn.

Drawing will trim the cache, see caching behaviour.

Example

glyph_brush.use_queue().draw(&mut gfx_encoder, &gfx_color)?;

pub fn queue_custom_layout<'a, S, G>(&mut self, section: S, custom_layout: &G) where
    G: GlyphPositioner,
    S: Into<Cow<'a, VariedSection<'a>>>, 

Queues a section/layout to be drawn by the next call of .use_queue().draw(..). Can be called multiple times to queue multiple sections for drawing.

Used to provide custom GlyphPositioner logic, if using built-in Layout simply use queue

Benefits from caching, see caching behaviour.

pub fn queue_pre_positioned(
    &mut self,
    glyphs: Vec<(PositionedGlyph<'font>, Color, FontId)>,
    bounds: Rect<f32>,
    z: f32
)

Queues pre-positioned glyphs to be processed by the next call of .use_queue().draw(..). Can be called multiple times.

pub fn keep_cached_custom_layout<'a, S, G>(
    &mut self,
    section: S,
    custom_layout: &G
) where
    S: Into<Cow<'a, VariedSection<'a>>>,
    G: GlyphPositioner, 

Retains the section in the cache as if it had been used in the last draw-frame.

Should not be necessary unless using multiple draws per frame with distinct transforms, see caching behaviour.

pub fn keep_cached<'a, S>(&mut self, section: S) where
    S: Into<Cow<'a, VariedSection<'a>>>, 

Retains the section in the cache as if it had been used in the last draw-frame.

Should not be necessary unless using multiple draws per frame with distinct transforms, see caching behaviour.

Important traits for &'_ mut [u8]

impl<'_> Write for &'_ mut [u8]impl<'_> Read for &'_ [u8]

pub fn fonts(&self) -> &[Font]

Returns the available fonts.

The FontId corresponds to the index of the font data.

pub fn add_font_bytes<'a: 'font, B: Into<SharedBytes<'a>>>(
    &mut self,
    font_data: B
) -> FontId

Adds an additional font to the one(s) initially added on build.

Returns a new FontId to reference this font.

Example

use gfx_glyph::{GlyphBrushBuilder, Section};

// dejavu is built as default `FontId(0)`
let dejavu: &[u8] = include_bytes!("../../fonts/DejaVuSans.ttf");
let mut glyph_brush = GlyphBrushBuilder::using_font_bytes(dejavu).build(gfx_factory.clone());

// some time later, add another font referenced by a new `FontId`
let open_sans_italic: &[u8] = include_bytes!("../../fonts/OpenSans-Italic.ttf");
let open_sans_italic_id = glyph_brush.add_font_bytes(open_sans_italic);

pub fn add_font<'a: 'font>(&mut self, font_data: Font<'a>) -> FontId

Adds an additional font to the one(s) initially added on build.

Returns a new FontId to reference this font.

Trait Implementations

impl<'_, R: Resources, F: Factory<R>, H> Debug for GlyphBrush<'_, R, F, H>

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

Formats the value using the given formatter.

impl<'font, R: Resources, F: Factory<R>, H: BuildHasher> GlyphCruncher<'font> for GlyphBrush<'font, R, F, H>

fn pixel_bounds_custom_layout<'a, S, L>(
    &mut self,
    section: S,
    custom_layout: &L
) -> Option<Rect<i32>> where
    L: GlyphPositioner + Hash,
    S: Into<Cow<'a, VariedSection<'a>>>, 

Returns the pixel bounding box for the input section using a custom layout. The box is a conservative whole number pixel rectangle that can contain the section.

fn glyphs_custom_layout<'a, 'b, S, L>(
    &'b mut self,
    section: S,
    custom_layout: &L
) -> PositionedGlyphIter<'b, 'font> where
    L: GlyphPositioner + Hash,
    S: Into<Cow<'a, VariedSection<'a>>>, 

Returns an iterator over the PositionedGlyphs of the given section with a custom layout.

Important traits for &'_ mut [u8]

impl<'_> Write for &'_ mut [u8]impl<'_> Read for &'_ [u8]

fn fonts(&self) -> &[Font<'font>]

Returns the available fonts.

fn pixel_bounds<'a, S>(&mut self, section: S) -> Option<Rect<i32>> where
    S: Into<Cow<'a, VariedSection<'a>>>, 

Returns the pixel bounding box for the input section. The box is a conservative whole number pixel rectangle that can contain the section.

fn glyphs<'a, S>(
    &'b mut self,
    section: S
) -> Map<Iter<'b, (PositionedGlyph<'font>, [f32; 4], FontId)>, fn(&'b (PositionedGlyph<'font>, [f32; 4], FontId)) -> &'b PositionedGlyph<'font>> where
    S: Into<Cow<'a, VariedSection<'a>>>, 

Returns an iterator over the PositionedGlyphs of the given section.

fn glyph_bounds_custom_layout<'a, S, L>(
    &mut self,
    section: S,
    custom_layout: &L
) -> Option<Rect<f32>> where
    L: GlyphPositioner + Hash,
    S: Into<Cow<'a, VariedSection<'a>>>, 

Returns a bounding box for the section glyphs calculated using each glyph's vertical & horizontal metrics.

fn glyph_bounds<'a, S>(&mut self, section: S) -> Option<Rect<f32>> where
    S: Into<Cow<'a, VariedSection<'a>>>, 

Returns a bounding box for the section glyphs calculated using each glyph's vertical & horizontal metrics.