laser-dac

Unified DAC backend abstraction for laser projectors.

This crate provides a complete solution for communicating with various laser DAC hardware:

• Discovery: Automatically find connected DAC devices (USB and network)
• Streaming: Zero-allocation callback API with buffer-driven timing
• Backends: Unified interface for all DAC types

This crate does not apply any additional processing on points (like blanking), except to make it compatible with the target DAC.

⚠️ Warning: use at your own risk! Laser projectors can be dangerous.

Supported DACs

All DACs have been manually verified to work.

Quick Start

Connect your laser DAC and run an example. For full API details, see the documentation.

cargo run --example stream -- circle
cargo run --example stream -- triangle
cargo run --example callback -- circle      # with progress counter
cargo run --example frame_adapter -- circle # using FrameAdapter
cargo run --example reconnect -- circle     # auto-reconnect on disconnect
cargo run --example audio                   # audio-reactive (requires microphone)
cargo run --example avb_file -- circle      # write 6ch AVB-mapped WAV for validation

The examples run continuously until you press Ctrl+C.

Streaming API

The streaming API uses buffer-driven timing: your callback is invoked when the buffer needs filling. This provides automatic backpressure handling and zero allocations in the hot path.

use laser_dac::{list_devices, open_device, ChunkRequest, ChunkResult, LaserPoint, StreamConfig};

let devices = list_devices()?;
let device = open_device(&devices[0].id)?;

let config = StreamConfig::new(30_000);
let (stream, info) = device.start_stream(config)?;

stream.control().arm()?;

let exit = stream.run(
    // Producer callback - fills buffer with points
    |req: &ChunkRequest, buffer: &mut [LaserPoint]| {
        let n = req.target_points;
        for i in 0..n {
            buffer[i] = generate_point(i);
        }
        ChunkResult::Filled(n)
    },
    // Error callback
    |err| eprintln!("Stream error: {}", err),
)?;

Return ChunkResult::Filled(n) to continue, ChunkResult::End to stop gracefully.

Reconnecting Session (optional)

If you want automatic reconnection by device ID, use ReconnectingSession:

use laser_dac::{ChunkRequest, ChunkResult, LaserPoint, ReconnectingSession, StreamConfig};
use std::time::Duration;

let mut session = ReconnectingSession::new("my-device", StreamConfig::new(30_000))
    .with_max_retries(5)
    .with_backoff(Duration::from_secs(1))
    .on_disconnect(|err| eprintln!("Lost connection: {}", err))
    .on_reconnect(|info| println!("Reconnected to {}", info.name));

// Arm output as usual (this persists across reconnects)
session.control().arm()?;

let exit = session.run(
    |req: &ChunkRequest, buffer: &mut [LaserPoint]| {
        let n = req.target_points;
        for i in 0..n {
            buffer[i] = generate_point(i);
        }
        ChunkResult::Filled(n)
    },
    |err| eprintln!("Stream error: {}", err),
)?;

Note: ReconnectingSession uses open_device() internally, so it won't include external discoverers registered on a custom DacDiscovery.

Coordinate System

All backends use normalized coordinates:

• X: -1.0 (left) to 1.0 (right)
• Y: -1.0 (bottom) to 1.0 (top)
• Colors: 0-65535 for R, G, B, and intensity

Each backend handles conversion to its native format internally.

Data Types

Advanced Configuration

Color Delay (Scanner Sync Compensation)

Galvo mirrors need time to settle before the laser fires. color_delay shifts RGB+intensity channels relative to XY coordinates so colors arrive after the mirrors are in position.

use std::time::Duration;

let config = StreamConfig::new(30_000)
    .with_color_delay(Duration::from_micros(100));

Can also be changed at runtime via stream.control().set_color_delay(...).

Typical values: 50–200µs depending on scanner speed. Disabled by default.

Startup Blanking

Prevents the "flash on start" artifact by forcing the first points after arming to blank, giving mirrors time to reach their initial position.

use std::time::Duration;

let config = StreamConfig::new(30_000)
    .with_startup_blank(Duration::from_millis(2)); // default: 1ms

Set to Duration::ZERO to disable.

Features

By default, all DAC protocols are enabled via the all-dacs feature.

DAC Features

For example, to enable only network DACs:

[dependencies]
laser-dac = { version = "*", default-features = false, features = ["network-dacs"] }

Other Features

USB DAC Requirements

USB DACs (helios, lasercube-usb) use rusb which requires CMake to build.

Development Tools

IDN Simulator

The repository includes a debug simulator (in tools/idn-simulator/) that acts as a virtual IDN laser DAC. This is useful for testing and development without physical hardware.

# Build and run the simulator
cargo run -p idn-simulator

# With custom options
cargo run -p idn-simulator -- --hostname "Test-DAC" --service-name "Simulator" --port 7255

Features:

• Responds to IDN discovery (appears as a real DAC)
• Renders received laser frames as connected lines
• Handles blanking (intensity=0 creates gaps between shapes)
• Shows frame statistics (frame count, point count, client address)

Usage:

When the simulator is running, launch your work that scans for IDN devices. You can use this crate, or any other tool that supports IDN!

For a simple test, you can run one of our examples: cargo run --example stream -- circle

CLI Options:

Acknowledgements

• Helios DAC: heavily inspired from helios-dac
• Ether Dream DAC: heavily inspired from ether-dream
• Lasercube USB / WIFI: inspired from ildagen (ported from C++ to Rust)
• IDN: inspired from helios_dac (ported from C++ to Rust)

License

MIT