node-red-contrib-ledmatrix/11-ledmatrix.js

Contains the nodes used in TimeSquAir to use the LEDMatrix library

/**
    Copyright © 2015 Digital Airways (www.DigitalAirways.com)
    This work is free. You can redistribute it and/or modify it under the
    terms of the Do What The Fuck You Want To Public License, Version 2,
    as published by Sam Hocevar. 
    See http://www.wtfpl.net for more details.
 **/

module.exports = function(RED) {
    "use strict";
    var Mustache = require("mustache");
    var exec = require('child_process').exec;

    var CMD = "killall -9 led-matrix;";
    CMD += "killall -9 convert ;";
    CMD += "{{{script}}}";
	CMD += "pnmcat -l {{{src}}} /root/thethingbox/rpi-rgb-led-matrix-sh/col5.ppm > tmp;\n"
    CMD += "mv -f tmp {{{src}}};\n";
    CMD += "/root/rpi-rgb-led-matrix-master/led-matrix -r {{r}} -c {{c}} -d -t {{t}} -D {{D}} -m {{m}} {{p}} {{{src}}} 2> {{{log}}};"

    function ledmatrix(n) {
        RED.nodes.createNode(this,n);

        this.time = n.time;
        this.speed = n.speed;

        var node = this;

        this.on('input', function (msg) {
            var speed_value = typeof msg.speed == "undefined" || msg.speed == null ? this.speed : msg.speed;
            var time = typeof msg.time == "undefined" || msg.time == null ? this.time : msg.time;
			msg.testintensity = msg.intensity ? 100 - parseInt(msg.intensity) : 20;
			switch(parseInt(speed_value)){
				case 0:
					var speed = 0;
				break;
				case 1:
					var speed = 100;
				break;
				case 2:
					var speed = 70;
				break;
				case 3:
					var speed = 50;
				break;
				case 4:
					var speed = 30;
				break;
				case 5:
					var speed = 10;
				break;
				default:
					var speed = 50;
				break;
			}
            var params = {
                r: 16,
                c: 1,
                t: time,
                D: 1,
                m: speed,
                p: (speed==0)?"-p 5":"",
				intensity: msg.intensity ? 100 - parseInt(msg.intensity) : 20,
                src: "/root/userdir/ledmatrix/final.ppm",
                log: "/root/userdir/ledmatrix/log.txt",
                script: msg.cmd
            }
            var cmd = Mustache.render(CMD, params);

            params = {
                finalppm: "/root/userdir/ledmatrix/final.ppm"
            }

            cmd =  Mustache.render(cmd, params);

            var child = exec(cmd, { encoding: "binary", maxBuffer: 10000000 }, function(err, stdout, stderr) {

            });
        });
    }
    RED.nodes.registerType("ledmatrix", ledmatrix);

}