Set values from outside a node group

Hello,

I have created a node group that has inside a value I’d like to set from outside but there is no socket in this setting. Several nodes haven’t always sockets to connect it (X/Y Blur, HueSatValue, sphere of the Normal, etc).
Is there a way to connect it anyway?
Maybe with driver’s expression but I didn’t succeed to do it.

Thanks if you have any ideas! :slight_smile:


Inside node group :


i can’t reproduce it. if you add another Hue/saturation/value node, is it with no input socket as well?

Yes, some nodes haven’t socket inputs to theirs settings. HueSaturationValue for example, the blur nodes, the keyer node etc.

If the node has no input socket you can’t do much. The only solution would be to use drivers, but…

There are workarounds for some scenarios.
Let me give a few:

  1. Blur: Set blurriness inside group much higher than you need and use “Size” input.
  2. A trick with angle of “Normal” node:

In Cycles it’s easier then in compositing, but in compositing it’s also possible.
Below you’ll see two setups in cycles that give exactly the same, the lower one can be used to “extract” normal node and plug angles to the input of the group.


… and here goes the setup in compositing. It’s a bit more complex, because we don’t have vector math node, so we have to calculate “dot product” manually:


Perhaps there also are workarounds for other scenarios. If you have any specific need, let me know, maybe I’ll come up with something.

Thank you Bartek for the normal node workaround. It was exactly something like that I was looking for! I will use it quite a lot with the position data.