node-red-contrib-openpixelcontrol

THIS NODE IS CURRENTLY WORK IN PROGRESS AND FOR PUBLIC USAGE

A node to stream output to an openpixelcontrol server. The OPC-Protocol is a lightweight and simple TCP network protocol to change several RGB-color values of lights or LEDs. As the protocol is frame streamlined is typically used for LED light strips arrangements but basically it depends on the server implementation. Therefore the OPC supports a channel and command field to address other systems or run system specific commands.

See OPC Server for information how to setup a openpixelcontrol server on a Raspberry with an attached WS2812 LED strip.

This node-set consists of the following nodes:

• colorspot: highlights pixel with a given width and color, can be used to create an empty buffer as well
• colormix: transform one or multiple inputs (array) to a mixed color array. (TODO: You can mirror or mask data as well)
• opc-client: the node will collect input data and send new data at the defined updaterate (eg. 50Hz).

Install

currently from git only

Usage

Inputs Color Mixing

Performance

The node respects the nodejs underlying buffers performance recommendations (buffers from pool <4k, Uint8arrays, array reusage, unsafe alloc).

TBD

Examples

Animation

Mixing colors

Websocket Bridge to use WebAudio

FFT on client per Webaudio Altenrative https://www.npmjs.com/package/fft.js

Using chroma.js mix colors easy

chroma.js https://github.com/colorjs

Timing, Synchronisation and Playback

FSM node

FFT with the RaspberryPi

Testing

Testing can be done by simulation of an OPC Server witn an OpenGL output, so you do not need the LEDs physically. OPC Simulator (OpenGL): https://github.com/zestyping/openpixelcontrol

OPC Server

There are different openpixelcontrol servers available, like fadecandy. Nodejs OPC Client and Server: openpixelcontrol-stream Nodejs OPC Server für RPI ws2812 native: https://github.com/bbx10/node-opc-server

RaspberryPi

For the reaspberry Pi

Testsetup with WS2812: http://popoklopsi.github.io/RaspberryPi-LedStrip/?_escaped_fragment_=/ws2812#!/ws2812

native ws2812 rasppbery: https://github.com/jgarff/rpi_ws281x Nodejs Wrapper: https://github.com/beyondscreen/node-rpi-ws281x-native

Related Work

https://flows.nodered.org/node/node-red-contrib-ola https://flows.nodered.org/node/node-red-contrib-rpi-ws2801 https://flows.nodered.org/node/node-red-node-pi-neopixel https://www.openlighting.org/ http://openpixelcontrol.org/ https://github.com/scanlime/fadecandy https://github.com/zestyping/openpixelcontrol

Working with colors

https://github.com/brehaut/color-js https://github.com/bgrins/TinyColor http://gka.github.io/chroma.js/

Useful other nodes

http://flows.nodered.org/node/node-red-contrib-looptimer http://flows.nodered.org/node/node-red-contrib-stoptimer http://flows.nodered.org/node/node-red-contrib-curve