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ArtnetOutModule

Packs the current pixel frame from a named source into Art-Net OpDmx packets and sends them via UDP. 510 DMX bytes (= 170 RGB pixels) per packet → multi-universe at large geometries (e.g. 128×128×1 = 49 152 RGB bytes = 97 universes per frame, ~6 Mbps at 50 fps). Runs on core 1 (set via constructor setCoreAffinity(1)); reads frames cross-core from the source's DataBuffer<RGB> via a single acquire/release pair — no per-frame copy on the consumer side.

Wire format (one Art-Net OpDmx packet per universe, sent to dest_ip:6454):

"Art-Net\0"          8 bytes  ID
0x00 0x50            2 bytes  OpCode (OpDmx, little-endian)
0x00 0x0e            2 bytes  ProtVer 14 (big-endian per spec)
seq                  1 byte   sequence (0 = ignore)
phys                 1 byte   physical port (0)
uni_lo uni_hi        2 bytes  universe (little-endian)
len_hi len_lo        2 bytes  DMX byte count (big-endian)
<data>               1..510 bytes  RGB triplets

End-user reference

Control Type Range / default Notes
enabled toggle true
source text ripples-0 Module id whose frame to send (resolved via DataRegistry)
dest_ip text 255.255.255.255 Receiver IP (broadcast by default; set to a specific Art-Net node)
universe range 0..15 / 0 Starting Art-Net universe number (subsequent packets increment)

Developer reference

  • Constructor: setCoreAffinity(1) — runs on APP_CPU so the consumer doesn't share core 0 with the producer.
  • setup() — udp_.begin() (bind ephemeral source port), resolve_buf_() (DataRegistry lookup by source id).
  • onUpdate(key) — for source edits, re-call resolve_buf_().
  • loop20ms() — buf_->try_acquire_read() (cross-core SPSC, release/acquire ordering); if null (no new frame), return early. Pack one Art-Net OpDmx packet per 510-byte universe slice via pack_header(), send via udp_.send(), buf_->release_read().
  • pack_header() — public static helper exposed for test_artnet_packing.cpp.