lichtung-plot

lichtung-plot is a strongly typed scientific renderer for owned immutable display values. It publishes outlined SVG and PNG artifacts and can also publish canonical SVG with preserved text from the same opaque rendered scene.

This first standalone-boundary release intentionally has no dependency on the Lichtung analysis, pipeline, asset, or reporting crates. Callers supply precomputed inferential annotations as ordinary plotting data.

The renderer is maintained in its own repository. Its architecture and output contracts live in specs/; user guides live in docs/.

use lichtung_plot::{NumericValues, Plot};

Plot::scatter(
    NumericValues::new("x", [1.0, 2.0, 3.0]),
    NumericValues::new("y", [1.5, 2.5, 2.0]),
)
.svg("scatter")?; // Publishes scatter.svg.
# Ok::<(), Box<dyn std::error::Error>>(())

Themes And Composition

Omitting a theme selects Publication for a standalone Plot and for the Canvas root. Canvas::theme replaces that root; child Plots without their own theme inherit it. Plot::theme completely replaces the inherited theme for only that Plot.

use lichtung_plot::{Canvas, NumericValues, Plot, Theme};

let canvas = Canvas::grid(1, 2)?
    .theme(Theme::Nature)
    .panel(0, 0, Plot::scatter(
        NumericValues::new("x", [1.0, 2.0]),
        NumericValues::new("inherited", [1.0, 2.0]),
    ))?
    .panel(0, 1, Plot::scatter(
        NumericValues::new("x", [1.0, 2.0]),
        NumericValues::new("replacement", [2.0, 1.0]),
    ).theme(Theme::Science))?;
# let _ = canvas;
# Ok::<(), lichtung_plot::Error>(())

Fonts

Outlined SVG and PNG generation resolve installed system fonts from this ordered stack and never download or embed font files:

Noto Sans, Noto Sans CJK SC, DejaVu Sans, Liberation Sans, Arial, sans-serif

The normal .svg(path) publication method converts all text to vector glyph paths. Recipients therefore do not need the generation fonts, but the exact paths depend on the fonts installed in the generation environment and the text is no longer selectable or searchable. .svg_preserve_text(path) instead publishes the canonical SVG with accessible, selectable, searchable, and editable <text> elements; its displayed text depends on fonts available to the viewer.

Output Formats

Publication SVG with outlined text, preserve-text SVG, and PNG are unconditional crate capabilities. Terminal paths are base destinations: SVG methods append .svg and PNG methods append .png unless the final filename already has the complete expected suffix under ASCII case-insensitive comparison. Existing filename text is never replaced, so report.v1 becomes report.v1.svg and report.png passed to .svg becomes report.png.svg. PDF output is deliberately outside this crate.

Development

Font and text processing share one cumulative root limit of 1,000,000 actual processing visits. Record and byte admission are independent: copying or hashing key bytes does not carry a synthetic processing price. Searches through variable candidate, guide-owner, and retained-face lists still admit each examined entry before comparison, including the terminating match. See resource admission and release evidence for the numeric contract, refusal behavior, 2,048-word workload, and nine-case output and timing comparison. Counters are not CPU time or resident memory measurements.

The repository pins its Rust toolchain and tracks Cargo.lock. Run the complete read-only verification before committing:

just verify

Focused recipes include just test and just lint.