Module shaped_render 

Shaped-run render path with spacing/kerning deltas.

This module transforms a ShapedRun into a sequence of cell-ready placements that a renderer can consume to produce output with correct spacing, kerning, and ligature handling.

Design

The render path operates in sub-cell units (1/256 cell column) for precision, then quantizes to integer cell positions for the terminal grid. This preserves the kerning and spacing fidelity from the shaping engine while producing deterministic cell-grid output.

Pipeline

ShapedRun + text
    → ClusterMap (byte↔cell mapping)
    → ShapedLineLayout (cell placements with sub-cell spacing)
    → apply justification/tracking deltas
    → quantized cell positions for buffer rendering

Example

use ftui_text::shaped_render::{ShapedLineLayout, RenderHint};
use ftui_text::shaping::{NoopShaper, TextShaper, FontFeatures};
use ftui_text::script_segmentation::{Script, RunDirection};

let text = "Hello!";
let shaper = NoopShaper;
let features = FontFeatures::default();
let run = shaper.shape(text, Script::Latin, RunDirection::Ltr, &features);

let layout = ShapedLineLayout::from_run(text, &run);
assert_eq!(layout.total_cells(), 6);
assert_eq!(layout.placements().len(), 6);
assert_eq!(layout.placements()[0].render_hint, RenderHint::DirectChar('H'));

Structs

CellPlacement

A single cell placement in the shaped output line.

ShapedLineLayout

A line of shaped text ready for rendering.

SpacingDelta

A sub-cell spacing adjustment applied between or within clusters.

Enums

RenderHint

Hint for how to render a cell’s content.