Joris wrote:I've been racking my brain, but I can't think of a single way that the ArtNet protocol would allow us to send more than 512 channels on a single universe.
Since Artnet is based on the DMX protocol, the limit is 512 but you might want to talk with the guys at Enttec and see if there be a way for you to integrate their proprietary Plink protocol (which combines two universes into one 340 RGB fixtures over CAT6) into Resolume. That would allow to make a fixture that's 20x17 RGB pixels.
thomasl wrote:I d like to control low res led screen drapery, but one fixture has 2 universes. But I can't create fixture with more pixels like is possible put in one universe…and map this with more fixtures is not very practical…
How have you controlled your low res LED screen until now? With the "democratization" of LED fixtures and tape, we are bound to exceed 512 channels in a heartbeat, right?
Let's face it, to get even a super low res composition such as a 640x480 into an LED screen would require 640*480*3=921,600 DMX channels which would require 1800 universes! In comparison, a 1920x1080 video wall would require 12,150 universes to control 6,220,800 RGB pixels.
Unfortunately, the number of channel in DMX universe (2^8=512) is not in line with the RGB requirement since it leaves you with two lone channels (511 & 512) so you can't really make an RGB grid without a dead pixel.
Of course I'm not an expert and I don't know how the Enttec Protocol is designed but I'm sure that's why the Plink I mentioned above is 340 channels and not 341 since it's using DMX as the basis for calculation and a pixel cannot be "riding" two universes which would mean U1/511, 512 and U2/1. I'm assuming the 340 RGB pixel are equally divided between two universes as U1/1-510 and U2/1-510 and U1/511, 512 & U2/511, 512 are unused
There is a point where you need to use external hardware (video wall controller) and treat your LED screen as a screen not a sum of RGB pixels. That means the output for your LED wall would be via your GPU instead of Arnet.