10 Oct
2013
10 Oct
'13
9:28 p.m.
On 10/10/2013 08:37 PM, Lars Luthman wrote:
I would just bypass the LV2 host altogether and use
shared memory to get
the audio data to the GUI. This is what the DSSI plugin does. This means
that it will not work if the plugin and the GUI are running on separate
machines, but that seems to be pretty rare.
These days it not as rare as it used to be.
A scope is just 1D - say 1024 pixels width -> 1K values that need to be
transmitted from the back-end to the UI. No need to use shared memory,
really.
The only reason for using shmem would be transmitting _all_ the raw
audio-data for upsampling in the UI-thread[1]. But even so, 1.5 Mbit/sec
is nothing these days. Besides, up/down-sampling requires a ringbuffer
anyway, and shmem won't buy you anything.
Message-passing (LV2 Atom messages) can go directly into the UI's
ringbuffer (no extra copy) and will allow the UI to run remotely.
2c,
robin
[1] Upsampling can be CPU heavy, but since it's for display only, it
should not cause DSP load -> delegate to UI-thread.