Anders, I suspect (but as a non-Foundry employee, of course I cannot *know*) that what's happening here is that Nuke is needing the state of your Iop at two different OutputContexts, possibly because it's needing your output state at two different frames, for some reason, at the same time - perhaps for some time-based downstream processing, possibly?
Perhaps the right thing to do is to create a singleton instance of your socket communications object - perhaps even as a system service of some kind - and then call it from your Iop. That guarantees that only one instance of the comm system has been instantiated. Also, do check the 'frame' property of the OutputContext of the inputs to your node, and if you've already obtained the data for the specified frame, there would be no reason to get it again. I hope that helps some. Also, have you perhaps thought of implementing your node as a 'Reader' rather than an Iop? Iops pretty much assume inputs in the DAG, whereas Readers are sources of image data. Steve From: nuke-dev-boun...@support.thefoundry.co.uk [mailto:nuke-dev-boun...@support.thefoundry.co.uk] On Behalf Of Anders Langlands Sent: Friday, March 23, 2012 3:23 AM To: Nuke plug-in development discussion Subject: [Nuke-dev] nuke creating many instances of my iop I'm writing a plugin Iop that describes a no-inputs op which essentially just receives image data from a server (that is in turn accepting data from a renderer). I'm trying to understand the logic of when Nuke creates multiple instances of my Iop. In normal use I see nuke call MyIop::MyIop(Node*), then MyIop::attach(), then MyIop::_validate(), as expected. However in certain circumstances when I am pushing image data to my node across a socket, Nuke starts creating many instances of MyIop, then calling _validate() without calling attach() (which makes sense since I have not created any new nodes). This is causing me issues because every time _validate() is called MyIop tries to make a new connection to the server, which is bad. I understand from the docs that I shouldn't expect to only ever have one instance of MyIop for each node in the graph, but none of the circumstances listed for when this might happen seems to apply in this case. This seems to happen when I am pushing a lot of data to several nodes - every time there is a new bucket of image data passed from the server, I am calling flagForUpdate() and asapUpdate() from a listener thread. If I am rendering to say, 4 nodes, this can happen quite a lot. Is this expected behaviour? Or is it due to something I am doing? Should I be checking whether a MyIop instance is actually attach()ed to a node before doing any processing with it? I've been through all the docs that seem pertinent, but still I don't really understand why Nuke might be creating these extra instances of my iop. Cheers, Anders (CONFIDENTIALITY NOTICE: The information contained in this email may be confidential and/or privileged. This email is intended to be reviewed by only the individual or organization named above. If you are not the intended recipient, or an authorized representative of the intended recipient, you are hereby notified that any review, dissemination or copying of this email, or the information contained herein is strictly prohibited. If you have received this communication in error, please notify the sender by return email and delete this email from your system. Thank You.)
_______________________________________________ Nuke-dev mailing list Nuke-dev@support.thefoundry.co.uk, http://forums.thefoundry.co.uk/ http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-dev
