sacn
Version:
💡 🎠Send and Receive sACN data (DMX over IP)
146 lines (145 loc) • 6.88 kB
JavaScript
"use strict";
/**
* this is the low-level implementation of the E1.31 (sACN) protocol
*/
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.Packet = void 0;
const assert_1 = __importDefault(require("assert"));
const util_1 = require("./util");
const constants_1 = require("./constants");
/**
* This constructs a sACN Packet, either from an
* existing `Buffer` or from `Options`.
*/
class Packet {
constructor(input, sourceAddress) {
this.sourceAddress = sourceAddress;
/* eslint-disable lines-between-class-members */
/* root layer */
this.root_vector = constants_1.RootVector.DATA;
this.preambleSize = 0x0010; // =16 (unit16 hence the redundant 00s)
this.postambleSize = 0;
this.acnPid = constants_1.ACN_PID;
/* framing layer */
this.frame_vector = constants_1.FrameVector.DATA;
/* DMP layer */
this.dmp_vector = constants_1.DmpVector.DATA;
this.type = 0xa1; // = 61
this.firstAddress = 0;
this.addressIncrement = 1;
this.startCode = 0;
/* eslint-enable lines-between-class-members */
this.useRawDmxValues = false;
if (!input)
throw new Error('Buffer packet instantiated with no value');
if (input instanceof Buffer) {
const buf = input;
// If a buffer is supplied, ascertain that the packet implements ACN
// correctly, and that is it a data packet. Also asceratain that the
// UDP overhead is valid. Then fill up the class values.
/* root layer */
assert_1.default.strictEqual(buf.readUInt32BE(18), this.root_vector);
this.root_fl = buf.readUInt16BE(16);
assert_1.default.deepStrictEqual(buf.slice(4, 16), this.acnPid);
assert_1.default.strictEqual(buf.readUInt16BE(0), this.preambleSize);
assert_1.default.strictEqual(buf.readUInt16BE(2), this.postambleSize);
this.cid = buf.slice(22, 38);
/* frame layer */
assert_1.default.strictEqual(buf.readUInt32BE(40), this.frame_vector);
this.frame_fl = buf.readUInt16BE(38);
this.options = buf.readUInt8(112);
this.sequence = buf.readUInt8(111);
// eslint-disable-next-line no-control-regex, unicorn/no-hex-escape
this.sourceName = buf.toString('ascii', 44, 107).replace(/\x00/g, '');
this.priority = buf.readUInt8(108);
this.syncUniverse = buf.readUInt16BE(109);
this.universe = buf.readUInt16BE(113);
/* DMP layer */
assert_1.default.strictEqual(buf.readUInt8(117), this.dmp_vector);
this.dmp_fl = buf.readUInt16BE(115);
assert_1.default.strictEqual(buf.readUInt8(118), this.type);
assert_1.default.strictEqual(buf.readUInt16BE(119), this.firstAddress);
assert_1.default.strictEqual(buf.readUInt16BE(121), this.addressIncrement);
this.propertyValueCount = buf.readUInt16BE(123);
assert_1.default.strictEqual(buf.readUInt8(125), this.startCode);
this.privatePayload = buf.slice(126);
}
else {
// if input is not a buffer
const options = input;
// set constants
this.preambleSize = 0x0010;
this.root_fl = 0x726e;
this.frame_fl = 0x7258;
this.dmp_fl = 0x720b;
this.syncUniverse = 0; // we as a sender don't implement this
this.options = 0; // TODO: can we just set to 0?
// set properties
this.privatePayload = options.payload;
this.sourceName = options.sourceName || 'sACN nodejs';
this.priority = options.priority || 100;
this.sequence = options.sequence;
this.universe = options.universe;
this.cid = options.cid || constants_1.DEFAULT_CID;
// set computed properties
this.propertyValueCount = 0x0201; // "Indicates 1+ the number of slots in packet"
// We set the highest possible value (1+512) so that channels with zero values are
// treated as deliberately 0 (cf. undefined)
if (options.useRawDmxValues) {
this.useRawDmxValues = true;
}
}
}
get payload() {
return this.privatePayload instanceof Buffer
? (0, util_1.objectify)(this.privatePayload)
: this.privatePayload;
}
get payloadAsBuffer() {
return this.privatePayload instanceof Buffer ? this.privatePayload : null;
}
get buffer() {
const sourceNameBuf = Buffer.from(this.sourceName.padEnd(64, '\0'));
// eslint-disable-next-line unicorn/prefer-spread -- more readabile this way
const n = [].concat(
/* root layer */
(0, util_1.bit)(16, this.preambleSize), // 0,1 = preable size
(0, util_1.bit)(16, this.postambleSize), // 2,3 = postamble size
[...this.acnPid], (0, util_1.bit)(16, this.root_fl), // 16,17 = root fl
(0, util_1.bit)(32, this.root_vector), // 18,19,20,21 = Root_vector
[...this.cid], // 22-37 = cid
/* framing layer */
(0, util_1.bit)(16, this.frame_fl), // 38,39 = frame fl
(0, util_1.bit)(32, this.frame_vector), // 40,41,42,43 = frame vector
[...sourceNameBuf], // 44 - 107 = sourceName
(0, util_1.bit)(8, this.priority), // 108 = priority (8bit)
(0, util_1.bit)(16, this.syncUniverse), // 109,110 = syncUniverse
(0, util_1.bit)(8, this.sequence), // 111 = sequence
(0, util_1.bit)(8, this.options), // 112 = options
(0, util_1.bit)(16, this.universe), // 113,114 = universe
/* DMP layer */
(0, util_1.bit)(16, this.dmp_fl), // 115,116 = dmp_fl
(0, util_1.bit)(8, this.dmp_vector), // 117 = dmp vector
(0, util_1.bit)(8, this.type), // 118 = type
(0, util_1.bit)(16, this.firstAddress), // 119,120 = first adddress
(0, util_1.bit)(16, this.addressIncrement), // 121,122 = addressIncrement
(0, util_1.bit)(16, this.propertyValueCount), // 123,124 = propertyValueCount
(0, util_1.bit)(8, this.startCode), // 125 = startCode
(0, util_1.empty)(512));
for (const ch in this.payload) {
if (+ch >= 1 && +ch <= 512) {
if (this.useRawDmxValues) {
n[125 + +ch] = (0, util_1.inRange)(this.payload[ch]);
}
else {
n[125 + +ch] = (0, util_1.inRange)(this.payload[ch] * 2.55);
}
}
}
return Buffer.from(n);
}
}
exports.Packet = Packet;