Struct AxisCollection

pub struct AxisCollection<'a> { /* private fields */ }

Collection of axes in a variable font.

Converts user (fvar) locations to normalized locations. See Self::location.

See the Axis type for more detail.

Implementations

impl<'a> AxisCollection<'a>

pub fn new(font: &impl TableProvider<'a>) -> Self

Creates a new axis collection from the given font.

pub fn len(&self) -> usize

Returns the number of variation axes in the font.

pub fn is_empty(&self) -> bool

Returns true if the collection is empty.

pub fn get(&self, index: usize) -> Option<Axis>

Returns the axis at the given index.

pub fn get_by_tag(&self, tag: Tag) -> Option<Axis>

Returns the axis with the given tag.

Examples

let opsz = Tag::new(b"opsz");
assert_eq!(font.axes().get_by_tag(opsz).unwrap().tag(), opsz);

pub fn location<I>(&self, settings: I) -> Location

where I: IntoIterator, I::Item: Into<VariationSetting>,

Given an iterator of variation settings in user space, computes an ordered sequence of normalized coordinates.

• Setting selectors that don’t match an axis are ignored.
• Setting values are clamped to the range of their associated axis before normalization.
• If more than one setting for an axis is provided, the last one is used.
• Omitted settings are set to 0.0, representing the default position in variation space.

Examples

let location = font.axes().location([("wght", 250.0), ("wdth", 75.0)]);

pub fn location_to_slice<I>( &self, settings: I, location: &mut [NormalizedCoord], )

where I: IntoIterator, I::Item: Into<VariationSetting>,

Given an iterator of variation settings in user space, computes an ordered sequence of normalized coordinates and stores them in the target slice.

• Setting selectors that don’t match an axis are ignored.
• Setting values are clamped to the range of their associated axis before normalization.
• If more than one setting for an axis is provided, the last one is used.
• If no setting for an axis is provided, the associated coordinate is set to the normalized value 0.0, representing the default position in variation space.

Examples

let axes = font.axes();
let mut location = vec![NormalizedCoord::default(); axes.len()];
axes.location_to_slice([("wght", 250.0), ("wdth", 75.0)], &mut location);

pub fn filter<I>( &self, settings: I, ) -> impl Iterator<Item = VariationSetting> + Clone

where I: IntoIterator, I::Item: Into<VariationSetting>,

Given an iterator of variation settings in user space, returns a new iterator yielding those settings that are valid for this axis collection.

• Setting selectors that don’t match an axis are dropped.
• If more than one setting for an axis is provided, the last one is retained.
• Setting values are clamped to the range of their associated axis.

Examples

// Assuming a font contains a single "wght" (weight) axis with range
// 100-900:
let axes = font.axes();
let filtered: Vec<_> = axes
    .filter([("wght", 400.0), ("opsz", 100.0), ("wght", 1200.0)])
    .collect();
// The first "wght" and "opsz" settings are dropped and the final
// "wght" axis is clamped to the maximum value of 900.
assert_eq!(&filtered, &[("wght", 900.0).into()]);

pub fn iter(&self) -> impl Iterator<Item = Axis> + 'a + Clone

Returns an iterator over the axes in the collection.

Trait Implementations

impl<'a> Clone for AxisCollection<'a>

fn clone(&self) -> AxisCollection<'a>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.