panes 0.1.0

Every layout engine you've found is welded to a renderer. You need the math without the framework.

panes is a spatial layout engine that computes rectangles without rendering them.

Describe panels in rows, columns, and presets. panes solves the geometry via Taffy's flexbox engine and hands back a map of PanelId → Rect. No framework. No widget system. No opinions about pixels.

Proof

use panes::{Layout, Rect};

let resolved = Layout::master_stack(["editor", "chat", "status"])
    .master_ratio(0.6)
    .gap(1.0)
    .resolve(80.0, 24.0)?;

for (id, rect) in resolved.iter() {
    println!("{id}: {rect:?}");
}
// PanelId(0): Rect { x: 0.0, y: 0.0, w: 47.5, h: 24.0 }
// PanelId(1): Rect { x: 48.5, y: 0.0, w: 31.5, h: 11.5 }
// PanelId(2): Rect { x: 48.5, y: 12.5, w: 31.5, h: 11.5 }

Install

cargo add panes

Usage

Pick a preset, build custom, or mutate at runtime.

// Preset — 15 built-in strategies
Layout::master_stack(["editor", "chat", "status"]).master_ratio(0.6).gap(1.0)

// Builder — nest rows, columns, constraints
let mut b = LayoutBuilder::new();
b.row(gap(8.0), |r| {
    r.panel("editor", grow(2.0))?;
    r.col(gap(0.0), |c| {
        c.panel("chat", grow(1.0))?;
        c.panel("status", fixed(3.0))?;
        Ok(())
    })
})?;

// Runtime — mutations, viewport, frame diffing
let mut rt = LayoutRuntime::from(layout);
rt.tree_mut().add_panel("terminal", grow(1.0))?;
let frame = rt.resolve(80.0, 24.0)?;
let diff = frame.diff();

Adapters convert rects to renderer-native types:

Documentation

See the User Guide for the full API: all 15 presets, the layout macro, TOML configuration, runtime mutations, frame diffing, animation, and render adapters.

License

MIT or Apache 2.0, at your option. See LICENSE-MIT and LICENSE-APACHE.