uzor-render-tiny-skia 1.3.0

//! CPU software rasterizer backend using `tiny-skia` + `fontdue`.
//!
//! Provides a pure-Rust, zero-GPU rendering context that implements the
//! [`uzor::render::RenderContext`] trait via [`TinySkiaCpuRenderContext`].

mod context;

pub use context::TinySkiaCpuRenderContext;

// ---------------------------------------------------------------------------
// Phase 4 cluster-shaping spot-checks
// ---------------------------------------------------------------------------

#[cfg(test)]
mod shaper_tests {
    use uzor::render::TextMetrics;
    use super::TinySkiaCpuRenderContext;

    fn ctx() -> TinySkiaCpuRenderContext {
        TinySkiaCpuRenderContext::new(1, 1, 1.0)
    }

    const FONT: &str = "16px sans-serif";

    /// "Hello" → 5 clusters, x_offset strictly increasing.
    #[test]
    fn hello_five_clusters() {
        let glyphs = ctx().measure_text_glyphs("Hello", FONT);
        assert_eq!(glyphs.len(), 5, "expected 5 clusters for 'Hello', got {:?}", glyphs);
        for (i, g) in glyphs.iter().enumerate() {
            let expected = ["H", "e", "l", "l", "o"][i];
            assert_eq!(g.cluster, expected, "cluster[{i}] mismatch");
        }
        // x_offsets must be non-decreasing
        for w in glyphs.windows(2) {
            assert!(
                w[1].x_offset >= w[0].x_offset,
                "x_offset not increasing: {:?} >= {:?}", w[0].x_offset, w[1].x_offset
            );
        }
    }

    /// "café" → 4 clusters, with 'é' as a single cluster (not 'e' + combining).
    #[test]
    fn cafe_four_clusters() {
        let glyphs = ctx().measure_text_glyphs("caf\u{00e9}", FONT);
        assert_eq!(glyphs.len(), 4, "expected 4 clusters for 'café', got {:?}", glyphs);
        assert_eq!(glyphs[3].cluster, "\u{00e9}", "last cluster should be é (U+00E9)");
    }

    /// "hi 👋" → 4 clusters: 'h', 'i', ' ', and the wave emoji as one cluster.
    #[test]
    fn emoji_one_cluster() {
        let text = "hi \u{1F44B}"; // U+1F44B = waving hand
        let glyphs = ctx().measure_text_glyphs(text, FONT);
        assert_eq!(glyphs.len(), 4, "expected 4 clusters for 'hi 👋', got {:?}", glyphs);
        assert_eq!(glyphs[3].cluster, "\u{1F44B}", "emoji should be one cluster");
    }

    /// Empty string → empty Vec.
    #[test]
    fn empty_string_empty_vec() {
        let glyphs = ctx().measure_text_glyphs("", FONT);
        assert!(glyphs.is_empty(), "empty string should return empty Vec");
    }
}