Martin Spott schreef:
> Well, we've been driving two 'external' displays on last years LinuxTag
> exhibition using the 'generic' protocol. We were surprised to encounter
> a significant performance hit on the master machine serving two clients
> at 20 Hz. Throttling the thing down to 10 Hz made the whole setup
> flyable again.
> Yet this might look different if such master does nothing but FDM
> output via network,
>       Martin.
Keep in mind that the Generic protocol is one of the most inefficient 
for real-time data communication, as it communicates via plain text. If 
you want something that goes over 100Hz, you need to think of a binary 
system. For an FDM connecting to a visual system it's basically nothing 
more than 18 floating point values (x,y,z, rotation xyz and first and 
second order derivatives for smoothing) resulting in a 72-byte data 
packet, which is doable.

To put it into perspective, the same 18 values would take up at least 
200 bytes (characters), not counting newlines and frame separators, as 
each floating point would need at least 10 characters to be represented 
at least a bit accurately, and still you have to cope with international 
issues (comma vs. decimal point) when you're using the generic protocol. 
Plus a terrible loss in resolution as the max. resolution for a plain 
text channel can be at most to the 10th decimal place (at least, in 
standard format) where a double floating point can carry much more 
accurate data.

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