iced_nodegraph 0.5.0

Nodes are ordinary iced widgets - sliders, text inputs, whatever your view builds - placed on an infinite zoom/pan canvas and wired together through typed pins. The widget holds no graph state: your application owns the data model, and connections, moves, and deletes arrive as messages, like any other iced widget. Everything on the canvas is drawn by a single WGPU pipeline as signed distance fields, so it stays sharp at every zoom level and handles graphs with hundreds of nodes.

Getting started

cargo add iced_nodegraph
cargo add iced --features wgpu

use iced_nodegraph::prelude::*;
use iced::{Element, Point};

fn view(&self) -> Element<'_, Message> {
    node_graph()
        .on_connect(|from, to| Message::Connected(from, to))
        .on_move(|delta, node_ids| Message::Moved(delta, node_ids))
        // A node is an id, a position, and any iced widget as content.
        .push_node(node(0, Point::new(200.0, 150.0), my_node_widget()))
        .push_node(node(1, Point::new(525.0, 175.0), another_node()))
        // An edge connects two pins, addressed as (node id, pin id).
        .push_edge(edge((), PinRef::new(0, 0), PinRef::new(1, 0)))
        .into()
}

node(..) and edge(..) are builders: chain .style(..) for per-node and per-edge looks, starting from presets like NodeStyle::input or EdgeStyle::error that derive from the theme like iced's button::success. Ids are yours: name the node, pin, edge and anchor id types once on an Ids marker (usize everywhere by default). The crate docs cover styling, connection validation, and the callback contract in detail. A complete runnable graph with typed pin payloads and live evaluation is examples/basic.rs (cargo run -p iced_nodegraph --example basic).

Demos

Every demo runs natively and in the browser.

cargo run -p demo_hello_world             # also: demo_styling, demo_interaction, demo_shader_editor
cargo run --release -p demo_500_nodes

Controls

Ctrl is Cmd on macOS. On the web, clone avoids Ctrl/Cmd+D (the browser's bookmark shortcut) and delete drops the Backspace alternative (legacy back-navigation). Every binding is host-rebindable through NodeGraph::keymap - see the Keymap type. Connections snap while dragging near a compatible pin - like plugging in a cable - rather than on mouse release, and compatible targets pulse during the drag. A route attaches and detaches the same way, during the drag rather than on release.

Anchor delete and detach ride the pan button as a travel-free click, so a right-DRAG starting on an anchor still pans; they follow a rebound pan_button. The routing gestures need on_anchor_create, on_route_attach and on_route_detach wired, anchor delete needs on_anchor_delete, and moving an anchor needs on_anchor_move - which also gates the core's hover highlight and the grab cursor, so a host wiring delete but not move gets a working delete on a core that never lights up. An unwired gesture leaves its zone inert rather than reporting into the void.

The minimap is opt-in through NodeGraph::minimap; without it the two map rows do not apply and the corner stays empty canvas. It takes a press before any node under it does, and reports the camera it steers through on_camera.

How it works

Your app owns the graph. The widget is stateless between frames: it renders the nodes and edges you pass in and reports intent (on_connect, on_move, on_delete, ...) through callbacks. Your update logic applies the change and the next view reflects it - the plain iced loop, no hidden state to sync.

One GPU pipeline. Node bodies, edges, pins, shadows, and the background grid are compiled into a single signed-distance-field scene and rendered by the in-tree iced_nodegraph_sdf crate. A compute-shader tile index culls per pixel, and animated stroke patterns drive their own redraws. Details in ARCHITECTURE.md.

Typed coordinates. Screen space and world space are distinct euclid types, so mixing them up is a compile error.

Compatibility

• Targets iced 0.14 with the wgpu renderer (the SDF pipeline has no tiny-skia fallback).
• Native: Windows, macOS, Linux. Web: WebAssembly on WebGPU-capable browsers - there is no WebGL fallback, so Chrome/Chromium is recommended.
• Pre-1.0: minor releases may change the API. See the CHANGELOG.

Development

The workspace contains the widget (iced_nodegraph), the SDF renderer (iced_nodegraph_sdf), and the demos.

cargo fmt --all -- --check
cargo clippy -p iced_nodegraph -p iced_nodegraph_sdf --all-targets -- -D warnings
ICED_TEST_BACKEND=tiny-skia cargo test -p iced_nodegraph
cargo test -p iced_nodegraph_sdf -- --test-threads=1
cargo bench -p iced_nodegraph_bench  # CPU shape-evaluation cost
./build_docs.sh  # rustdoc + all demos as WASM (needs wasm-pack)

AGENTS.md has the full pre-push list, including the ignored orbit sweep and the workspace, bench and wasm checks.

License

MIT