Trait ab_glyph::ScaleFont

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pub trait ScaleFont<F: Font> {
Show 20 methods    // Required methods
    fn scale(&self) -> PxScale;
    fn font(&self) -> &F;
    fn codepoint_ids(&self) -> CodepointIdIter<'_> ⓘ;

    // Provided methods
    fn h_scale_factor(&self) -> f32 { ... }
    fn v_scale_factor(&self) -> f32 { ... }
    fn scale_factor(&self) -> PxScaleFactor { ... }
    fn ascent(&self) -> f32 { ... }
    fn descent(&self) -> f32 { ... }
    fn height(&self) -> f32 { ... }
    fn line_gap(&self) -> f32 { ... }
    fn glyph_id(&self, c: char) -> GlyphId { ... }
    fn scaled_glyph(&self, c: char) -> Glyph { ... }
    fn h_advance(&self, id: GlyphId) -> f32 { ... }
    fn h_side_bearing(&self, id: GlyphId) -> f32 { ... }
    fn v_advance(&self, id: GlyphId) -> f32 { ... }
    fn v_side_bearing(&self, id: GlyphId) -> f32 { ... }
    fn kern(&self, first: GlyphId, second: GlyphId) -> f32 { ... }
    fn glyph_bounds(&self, glyph: &Glyph) -> Rect { ... }
    fn glyph_count(&self) -> usize { ... }
    fn outline_glyph(&self, glyph: Glyph) -> Option<OutlinedGlyph> { ... }
}

Expand description

A Font with an associated pixel scale. This can be used to provide pixel scale values for glyph advances, heights etc.

Example

use ab_glyph::{Font, FontRef, PxScale, ScaleFont};

let font = FontRef::try_from_slice(include_bytes!("../../dev/fonts/Exo2-Light.otf"))?;

// Associate the font with a scale of 45px
let scaled_font = font.as_scaled(PxScale::from(45.0));

assert_eq!(scaled_font.height(), 45.0);
assert_eq!(scaled_font.h_advance(scaled_font.glyph_id('b')), 21.225);

// Replace associated scale with another
let scaled_font = scaled_font.with_scale(180.0);

assert_eq!(scaled_font.height(), 180.0);
assert_eq!(scaled_font.h_advance(scaled_font.glyph_id('b')), 84.9);

Required Methods§

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fn scale(&self) -> PxScale

Returns the pixel scale associated with this font.

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fn font(&self) -> &F

Returns a font reference.

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fn codepoint_ids(&self) -> CodepointIdIter<'_> ⓘ

Returns an iterator of all distinct (GlyphId, char) pairs. Not ordered.

Same as Font::codepoint_ids.

Provided Methods§

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fn h_scale_factor(&self) -> f32

Scale factor for unscaled font horizontal values.

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fn v_scale_factor(&self) -> f32

Scale factor for unscaled font vertical values.

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fn scale_factor(&self) -> PxScaleFactor

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fn ascent(&self) -> f32

Pixel scaled glyph ascent.

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fn descent(&self) -> f32

Pixel scaled glyph descent.

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fn height(&self) -> f32

Pixel scaled height ascent - descent.

By definition of PxScale, this is self.scale().y.

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fn line_gap(&self) -> f32

Pixel scaled line gap.

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fn glyph_id(&self, c: char) -> GlyphId

Lookup a GlyphId matching a given char.

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fn scaled_glyph(&self, c: char) -> Glyph

Construct a Glyph with the font’s pixel scale at position point(0.0, 0.0).

Example

let scaled_font = font.as_scaled(50.0);

let a1 = scaled_font.scaled_glyph('a');
let a2 = font.glyph_id('a').with_scale(50.0); // equivalent

assert_eq!(a1.scale, PxScale::from(50.0));
assert_eq!(a1.position, point(0.0, 0.0));