lightweight-pdf-layout 0.1.0

Layoutable trait, pagination and text wrapping for lightweight-pdf
Documentation 
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use lightweight_pdf_core::FontKey;

/// Per-font metrics, normalized to 1000 units-per-em (PDF/Type1
/// convention). `lightweight-pdf-layout` never sees font bytes — only this.
pub trait FontMetrics {
    /// Advance width for one character, in 1/1000 em. Implementors must
    /// return *some* usable width even for unrepresentable characters
    /// (e.g. a notdef/fallback width) so wrapping code never has to
    /// special-case "no metric available".
    fn advance(&self, ch: char) -> f32;
    fn ascent(&self) -> f32;
    fn descent(&self) -> f32;
}

/// `lightweight-pdf-layout`'s only dependency on fonts: given a [`FontKey`], hand
/// back metrics. Implemented by the facade crate, which bridges to
/// `lightweight-pdf-fonts::FontData` (ADR-010).
pub trait FontResolver {
    fn metrics(&self, key: FontKey) -> &dyn FontMetrics;
}