On 03/03/15 10:58, Olivier Baudu wrote:
Hi list,
Until now, and as far as I (think I) can remember, GEM was rendering frames even if the window (with or without border) was :
- out of the screen
- reduce in the tool-bar
- hidden by an other window
The last time I use this property was on an Ubuntu 13.10 both with "pd-vanilla + gem from the depot" and " pd-extended" (but I can't give you versions... because... well, I don't know them... sorry)
On several different patches, I recorded GEM content (which was not display on my desktop because of "offset" option) with the combo [pix_record] / v4l2loopback in order to make a "fake webcam" to stream. It was working. It is still working on computers where those patches where installed.
Now, I am on Ubuntu 14.04 / GEM: 0.93.3 and if anything is put over the GEM content, it seems to be that none of the pixel "under" is rendered.
If I open the v4l2loopback device on VLC (or whatever) and hide part of the GEM window (even by dragging icons from my desktop), those parts are not refresh anymore.
Does GEM change its way to render ? Is the Ubuntu 14.04 display different ? Do I misunderstood something ?
I don't know the answers to those questions ... it could be optimisation at one of several levels ... but in very many use-cases not rendering content that is covered would be a good thing, and a big improvement to performance.
In that case setting up a virtual X display without a monitor may be the answer, though depending on what you are doing it could make a difference to what is hardware accelerated.
It was some time ago that I last did that, but will look up the method, essentially it involves launching a new X-server instance and running pd with its DISPLAY env set to that display.
Simon