This is a complete solution for sending and receiving dmx-data via Art-Net without the need of additional hardware

Credits

Art-Net™ is a trademark of Artistic Licence Engineering Ltd.

This work is basend on the node-red-contrib-artnet nodes developed by Gunnebo

The Art-Net library is taken from margau/dmxnet

Added the features introduced by node-red-contrib-artnet-plus by Hayden Donald

Main changes to the previous work

• Basically it is fully compatible to the payload format defined by gunnebo
• More than one universe can now be served
• Transitions got more attributes and features
• This module is fully functional without any additional hardware
• The sending is completely rewritten, so that you can't flood the artnet
• The transition engine is rewritten, so that only one interval timer with the required resolution ist doing the transition handling.

Install

Run the following command in the root directory of your Node-RED install. Usually this is ~/.node-red

npm install @bannsaenger/node-red-contrib-artnet-controller

Or even inside of Node-RED with the palette manager.

Using

Sending DMX-Data

First you must specify a Art-Net controller configuration node. The controller is bound to one or all ip addresses found on the system and handles the Art-Net polling and shows up as an Art-Net node in the network.

For sending data there must be a Art-Net Sender configuration node. This node holds one universe of dmx-data and hadles the sending of this universe to the network.

To get dmx-data out to the network you use the Art-Net Out node. This is basically connected to a Art-Net Sender node. If you mass am msg object without additional addressing, the dmx values are sent to the Art-Net Sender specified in the Art-Net Out node.

If you pass additional addressing information, the Art-Net Out node tries to find a sender with the given address information. If none is found the configured Art-Net Sender instance is taken.

msg.payload = {
  "net": 0,
  "subnet": 0,
  "universe": 1

• net - int: net in [0, 127]
• subnet - int: subnet in [0, 15]
• universe - int: universe in [0, 15]

Receiving DMX-Data

With the Art-Net In node you can receive dmx values. Each Art-Net In node must be bound to a existing Art-Net controller configuration node. You must specify a net, subnet and universe. Then the data can be received in form of buckets as decribed in Payload format later in this document or as a Uint8Array with the values of the whole universe.

Payload format

You can either set a single channel like the following example:

msg.payload = {
  "channel": 1,
  "value": 255 
};

• channel - int: address in [1, 512]
• value - int: value in [0, 255]

Or you can set multiple channels at once:

msg.payload = {
  "buckets": [
    {"channel": 1, "value": 255},
    {"channel": 4, "value": 0}
  ]
};

You can also fade to values, either for a single channel or multiple channels. You should specify the 'transition', a 'duration' in milliseconds and optional a number of repetitions. The value of -1 in 'repeat', forces the the transition to run infinitely till a value or other transtion is send on this channel. If a repetition is defined, a gap between repetitions can be defined. The transition ends with the target value, holds and starts again with the value before the transition.

msg.payload = {
    "transition": "linear",
    "duration": 5000,
    "repeat": 1,
    "gap": 1000,
    "buckets": [
      {"channel": 1, "value": 255},
      {"channel": 4, "value": 0}
    ]
}

• channel - int: address in [1, 512]
• value - int: value in [0, 255]

Optional you can define start values. These will not be sent immediately. Can also be specified in the trasition payload as well.

msg.payload = {
    "start_buckets": [
        {"channel": 1, "value": 255},
        {"channel": 4, "value": 123},
    ]
};

In order to perform arc transition (movement by arc) you shold specify more details:

msg.payload = {
    "transition": "arc",
    "duration": 2000,
    "arc": {
        "pan_channel": 1,
        "tilt_channel": 3,
        "pan_angle": 540,
        "tilt_angle": 255
    },
    "start": {"pan": 0, "tilt": 44},
    "center": {"pan": 127.5, "tilt": 63.75},
    "end": {"pan": 85, "tilt": 44}
};

where

• arc - channels that should be involved in arc transition (pan and tilt channels)
• start - initial channel's values (start point). By default: current channel's values.
• center - "center point" values
• end - terminal channel's values (end point)

In example above moving head will move by arc starting from {pan: 0, tilt: 44} to {pan: 85, tilt: 44}. Center point ({pan: 127.5, tilt: 63.75}) defines nominal circle center.

The 'repeat' value can also be added in this transition.

Attention using the arc feature

This "arc" feature behaves exact like the original module. But the description does not meet the reality. The start, center and end points are not realy channel values. Must be revised.

Changelog

0.1.4

• (Bannsaenger) added user defined error handler for dmxnet library. Works with dmxnet > 0.9.0. With versions prior to 0.9.0 the behaviour is like before
• (Bannsaenger) fixed the transfer of parameter port number to the dmxnet library

0.1.3

• (Bannsaenger) go back the original dmxnet dependecy

0.1.2

• (Bannsaenger) fix transition handling, more steps than values produces now a even timed transition with sometimes the same value in more than one step
• (Bannsaenger) fix start transition even if maxRate = 0

0.1.1

• (Bannsaenger) fix help for esta homepage

0.1.0

• (Bannsaenger) fixed some TypedInput issues
• (Bannsaenger) added ESTA type code to the "Art-Net Controller" and clarified OEM-code descriptions. OEM-code does not include the manufacturer code.

0.0.1

• (Bannsaenger) initial release

License

MIT License

Copyright (c) 2022 Bannsaenger [email protected]

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.