dear-node-editor

Safe Rust bindings for imgui-node-editor through the cimnodes_editor wrapper and a repository-owned C ABI shim.

This crate coexists with dear-imnodes:

• dear-imnodes wraps ImNodes and is the current wasm-capable node editor path.
• dear-node-editor wraps imgui-node-editor and is native-only in the first integration phase.

The native-only scope is a workspace integration boundary, not a claim that the upstream C++ library can never run on WebAssembly. This repository's WASM path uses an import-style provider module with explicit generated exports; node editor support needs its own provider wiring before it can be exposed safely on wasm.

The sys layer deliberately exposes NodeId, PinId, and LinkId as pointer-sized integer values instead of upstream C++ helper pointers. The safe layer wraps those values as Rust newtypes and uses RAII tokens for editor frames, nodes, pins, create/delete sessions, shortcuts, and style pushes.

Upstream Relationship

This crate is a safe Rust layer over:

• imgui-node-editor
• cimnodes_editor

The node_editor_showcase example follows the upstream blueprints example structure and uses the same style of stack layout calls (BeginHorizontal, BeginVertical, and Spring) through dear-imgui-rs safe wrappers. Those stack layout helpers are compatibility APIs implemented by dear-imgui-sys; they are not official Dear ImGui APIs.

The vendored native imgui-node-editor sources are MIT-licensed. See extensions/dear-node-editor-sys/third-party/cimnodes_editor/imgui-node-editor/LICENSE in the repository and dear-imgui-sys/THIRD_PARTY_NOTICES.md for the stack layout compatibility notice.

Compatibility

Quick Start

use dear_node_editor::{EditorContext, NodeEditorUiExt, NodeId, PinId, LinkId, PinKind};

fn setup(imgui: &dear_imgui_rs::Context) -> EditorContext {
    EditorContext::create(imgui)
}

fn draw(ui: &dear_imgui_rs::Ui, editor_ctx: &EditorContext) {
    let editor = ui.node_editor(editor_ctx, "node-editor", [0.0, 400.0]);

    editor.node(NodeId::new(1), |node| {
        ui.text("Node A");
        node.pin(PinId::new(11), PinKind::Output, |_pin| {
            ui.text("out");
        });
    });

    editor.node(NodeId::new(2), |node| {
        node.pin(PinId::new(21), PinKind::Input, |_pin| {
            ui.text("in");
        });
    });

    editor.link(LinkId::new(100), PinId::new(11), PinId::new(21));
    editor.end();
}

If an application stores dear_imgui_rs::Context and EditorContext in the same owner struct, declare EditorContext before the ImGui context so the editor is dropped first. Native imgui-node-editor state is tied to the owning ImGui context.

struct UiState {
    node_editor: dear_node_editor::EditorContext,
    imgui: dear_imgui_rs::Context,
}

The creation configuration is queryable through EditorContext::config():

fn inspect(editor: &dear_node_editor::EditorContext) {
    let config = editor.config();
    assert!(config.custom_zoom_levels.is_empty());
}

The lower-level RAII tokens are still available when manual scoping is clearer:

fn draw_manual(ui: &dear_imgui_rs::Ui, editor: &dear_node_editor::NodeEditorFrame<'_>) {
    let node = editor.begin_node(NodeId::new(1));
    ui.text("Node A");
    let pin = node.begin_pin(PinId::new(11), PinKind::Output);
    ui.text("out");
    pin.end();
    node.end();
}

Run the repository examples:

# Minimal interaction sample based on upstream basic-interaction-example.

cargo run -p dear-imgui-examples --bin node_editor_basic --features node-editor


# Blueprint-style showcase based on upstream blueprints-example.

cargo run -p dear-imgui-examples --bin node_editor_showcase --features node-editor