Node-RED + OLA: Smart DMX Channel Update Subflow

This Node-RED subflow receives a DMX update string (e.g. "255,,128,,,1") via msg.payload and sends an optimized update to an OLA (Open Lighting Architecture) universe.

Features

• Retrieves the current DMX state from the OLA REST API
• Updates only the specified channels; empty values ("") are ignored
• Channels with values that are already set (no actual change) are not updated — similar to how traditional lighting consoles behave
• Sends a minimal and efficient update containing only the changed channels
• Useful for integrating other systems or UIs with DMX lighting via OLA