TouchDesigner to Lights

Connect TouchDesigner's visual outputs to Spectralite via NDI for generative and data-driven lighting control.

Overview

TouchDesigner is a node-based visual programming environment for real-time interactive multimedia content. Spectralite receives TouchDesigner's NDI output. Lighting can then follow data, sensor input, or generative patterns.

What you'll need

• TouchDesigner (commercial or non-commercial license)
• Network connection between TouchDesigner and Spectralite
• Spectralite running on the same network

Quick start

1. Add an NDI Out TOP in TouchDesigner.
2. Connect your composition to NDI Out.
3. Enable the stream in Spectralite.
4. Create reactive effects using the NDI data.

Setting up NDI in TouchDesigner

Step 1: Add NDI Out TOP

1. Open your TouchDesigner project.
2. Add an NDI Out TOP operator to your network.
3. Connect your visual output to the NDI Out TOP input.
4. The NDI stream starts automatically when enabled.

Step 2: Configure NDI Out TOP

In the NDI Out TOP parameters:

• NDI Name: set a descriptive name (e.g., "TouchDesigner-Main").
• Active: enable to start transmission.
• Resolution: set output resolution (720p recommended).
• Pixel Format: RGBA or RGB (RGBA if you need an alpha channel).

Step 3: Verify output

1. Check the Info DAT in TouchDesigner to verify streaming.
2. Look for a network activity indicator.
3. Monitor frame rate in the performance monitor.

For detailed configuration, see TouchDesigner's NDI Out TOP documentation.

Connecting to Spectralite

Enable NDI in Spectralite

1. Open Spectralite.
2. Go to Edit > Inputs > NDI.
3. Enable NDI input enabled and Auto-discover sources.
4. This dialog does not show a source picker; TouchDesigner's stream is consumed by the NDI Input node in the Node Editor and by the built-in NDI Input layer effect.

Using TouchDesigner in Spectralite

There are two ways to use TouchDesigner's output in your lighting.

Quick start: built-in NDI layer

For immediate use, add an NDI layer directly to your timeline:

1. In the Timeline panel, click + Add new layer.
2. Select the built-in NDI Input effect.

TouchDesigner's output now drives your fixtures.

Advanced: custom effects with NDI nodes

For custom control over how TouchDesigner drives lighting:

1. Open the Node Editor.
2. Create a new effect or edit an existing one.
3. Add an NDI Input node to sample video data from TouchDesigner.
4. Connect it to other nodes to create custom generative lighting effects.

Optimization for performance

Reduce the NDI output resolution in TouchDesigner (720p is usually enough), cap network dimensions with a Limit TOP, and watch GPU memory for large textures. Use wired gigabit Ethernet, keep both systems on the same subnet, and monitor bandwidth inside TouchDesigner. In Spectralite, sample at a resolution matched to your fixture count and simplify effects when the NDI source is complex.

Common workflows

Generative lighting system

Autonomous lighting driven by algorithms:

1. Create generative networks (noise, feedback, particles) in TouchDesigner.
2. Use parameters to control behavior.
3. Output to Spectralite via NDI.
4. Lighting evolves based on the algorithm.

Sensor-reactive installation

Physical sensors control lighting via TouchDesigner:

1. Connect sensors to TouchDesigner (OSC, MIDI, serial, etc.).
2. Process sensor data into visual patterns.
3. Send to Spectralite via NDI.
4. Lighting responds to environmental input.

Audiovisual performance

Synchronized audio-reactive visuals and lighting:

1. Analyze audio in TouchDesigner.
2. Generate reactive visuals.
3. Send the same visual data to Spectralite.
4. Visuals and lights stay in sync because they share the source.

Data visualization

Transform data into lighting:

1. Fetch data in TouchDesigner (weather, social media, analytics).
2. Visualize as colors, patterns, or spatial data.
3. Output to Spectralite.
4. Lighting becomes a data display medium.

Advanced techniques

Multi-output setup

Send multiple TouchDesigner outputs:

1. Add multiple NDI Out TOPs for different compositions.
2. Name each descriptively (e.g., "TD-Zone1", "TD-Zone2").
3. Use different streams for different fixture groups.

Alpha channel control

Use transparency for intensity control:

1. Include an alpha channel in NDI output (RGBA format).
2. Sample alpha values in Spectralite.
3. Control fixture intensity based on alpha.
4. Use alpha transitions to drive fades.

CHOP-to-color mapping

Use TouchDesigner CHOPs for direct control:

1. Create CHOP networks for control data.
2. Convert to TOP (colors) for NDI transmission.
3. Each pixel represents a fixture or parameter.
4. Drive fixtures using TouchDesigner's data processing.

Instancing for complex patterns

Use geometry instancing in TouchDesigner:

1. Create instance positions and colors in TOPs.
2. Render instances to texture.
3. Send to Spectralite via NDI.
4. Each instance maps to a fixture.

Troubleshooting

Stream not appearing

1. Verify NDI Out TOP is Active.
2. Check both systems on the same network.
3. Verify the firewall allows NDI (port 5353 for discovery).
4. Check NDI Out TOP Info DAT for errors.

Frame rate issues

1. Optimize the TouchDesigner network (use Performance Monitor).
2. Reduce NDI output resolution.
3. Lower the Cook Rate on NDI Out TOP if real-time isn't critical.
4. Check GPU usage in Task Manager.

Network latency

1. Use a wired Ethernet connection.
2. Reduce output resolution.
3. Apply a Limit TOP to the network before NDI Out.
4. Monitor the network with the Network Performance window.

Color accuracy

1. Match color space settings (sRGB typical).
2. Check gamma in the rendering chain.
3. Verify pixel format (RGBA vs RGB).

Integration tips

OSC control

Control both applications simultaneously:

1. Send OSC to TouchDesigner for visuals.
2. Send OSC to Spectralite for direct control.
3. Use TouchDesigner as an OSC router or processor.

MIDI synchronization

Sync both applications to MIDI:

1. Route MIDI to TouchDesigner via MIDI In CHOP.
2. Route MIDI to Spectralite for direct control.
3. TouchDesigner processes MIDI for complex behaviors.
4. Lighting follows both direct and processed data.

Time-based control

Use timeline-based control in both:

1. TouchDesigner Timeline COMP for sequences.
2. Coordinate with Spectralite's timeline.
3. Pre-program synchronized shows.
4. Combine with live improvisation.

Resources

• TouchDesigner NDI Out TOP Documentation: official operator reference.
• General NDI Setup: generic NDI workflow.
• Node Editor: create NDI-reactive effects.

Related guides

• Resolume to Lights
• VDMX to Lights