Radiant

Radiant is a Windows-first Rust GUI library for serious desktop applications. It exposes one public API for declarative views, application state updates, layout, input, focus, styling, Vello-backed rendering, and retained GPU surfaces for dense realtime visuals.

Radiant is intended to stay application-independent. Product state, files, audio/plugin host behavior, and domain-specific naming belong in the host application; Radiant owns generic GUI primitives, runtime surfaces, paint plans, diagnostics, examples, and validation.

Start Here

Use the prelude and application builders for normal apps:

use radiant::prelude::*;

fn main() -> radiant::Result {
    radiant::window("Radiant Hello World").run(text("Hello, world!"))
}

Low-level runtime objects such as the minimal RuntimeBridge, cached RuntimeHostCapabilities, UiSurface, SurfaceNode, and NativeRunOptions remain supported for custom hosts, embedded surfaces, diagnostics, and advanced widgets. They are explicit control surfaces, not a second framework.

Documentation Map

• docs/API.md: application-facing API contract, examples, runtime model, and validation lane.
• docs/API_STYLE.md: preferred public API style, example style, and cleanup ticket criteria.
• docs/ARCHITECTURE.md: contributor map for ownership boundaries, platform seams, rendering boundaries, and validation slices.
• docs/TARGET.md: long-term project direction for a standalone, high-performance general-purpose GUI library.

Radiant uses the workspace CC0 1.0 license.

Examples

Examples are maintained API sandboxes and validation targets:

cargo run --example hello_world
cargo run --example generic_native
cargo run --example widget_gallery
cargo run --example waveform_view
cargo run --example curve_area_fill
cargo run --example timeline_editor
cargo run --example eq_editor
cargo run --example spectrogram

Run all checked examples with:

cargo test --examples

macOS Dev App Bundles

Direct Unix binaries with windows are not always visible as normal applications to macOS LaunchServices or app-level UI automation tools. Radiant ships a generic helper for host applications that need a LaunchServices-visible development .app wrapper around a prebuilt binary:

cargo build --release --bin my_app
RADIANT_DEV_APP_NAME="My App" \
RADIANT_DEV_APP_BINARY="$PWD/target/release/my_app" \
RADIANT_DEV_APP_BUNDLE_ID="com.example.my-app.dev" \
vendor/radiant/scripts/dev_app_bundle.sh --log

The helper stages target/dev-app/My App.app, writes a minimal Info.plist, copies the binary into Contents/MacOS, ad-hoc signs when possible, and launches through open. Set RADIANT_DEV_APP_PREPARE_ONLY=1 to stage without launching. This supports app-level automation attachment by app name or bundle id; Radiant's backend-neutral automation snapshots and flattened target projection remain the semantic UI source for tests, devtools, Computer Use sidecars, and future accessibility adapters.

For direct dev-app sidecars, set RADIANT_AUTOMATION_TARGET_EXPORT to a JSON path before launching. The native runtime writes the latest flattened target snapshot after surface refreshes, using atomic replacement and skipping unchanged payloads. Set RADIANT_AUTOMATION_TARGET_EXPORT_PRETTY=1 for readable JSON during manual automation work.

Validation

The normal local quality lane is documented in docs/API.md. The short version:

cargo fmt -- --check
cargo clippy --all-targets --all-features -- -D warnings
cargo test --lib --tests
cargo test --examples
cargo doc --no-deps
cargo test --doc

Portable library checks for the documented future Linux and macOS targets and the perf-harness smoke lane are also part of the full validation path.