Threading problems with sensor device

[Johnatan]

I have connected a sensor and am reading the values within a phyton script.
This script is based on an external library and contains a method that gives me a value as soon as the sensor changes (update rate of 200ms).

Now I have to pass this value to a node TD, but I get threading problems as soon as I do this.

Can anyone tell me something about this and how do I get my value from the sensorChange method into the TD value without creating threading issues?

Thanks a lot!

[malcolm]

You need to pass your value to the main thread using something like:

queue — A synchronized queue class

In your worker thread you put the value into that queue, then in a Execute DAT or some DAT script you pull the value off of that queue and apply it to the node however you need (set it’s parameter value etc).

[Johnatan]

Thanks Malcom, I will check that out

[raganmd]

There’s an example of threading in TouchDesigner using a queue here:

TouchDesigner | Multi-Threading

This builds on a larger conversation in an old thread here:

multithreading in python?

A good way to know what is allowed and what is not: the code in your thread should be able to run standalone in python33.exe, outside of TouchDesigner. If it is using anything that TouchDesigner provides such as OPs, storage etc, then you are creating race conditions that will potentially cause crashes. For counters you need to use locks: eli.thegreenplace.net/2012/01/04 … processing The difference with a CHOP Execute DAT is that that DAT always executes in the main thread, so there is no cha…