Function insert_and_render_outline 

fn insert_and_render_outline(
    renderer: &mut impl GlyphRenderer,
    glyph: &GlyphOutline,
    outline_transform: Affine,
    cache_key: GlyphCacheKey,
    glyph_atlas: &mut GlyphAtlas,
    image_cache: &mut ImageCache,
    tint_color: AlphaColor<Srgb>,
) -> CacheResult

Insert an outline glyph into the atlas and render it from there.

Allocates atlas space (the insert returns the per-page command recorder) and records rasterisation commands. The upstream caller is responsible for checking the cache first and only calling this on a miss.