How to disable controls if an input is connected?

[magneto]

Hi,

I am making an asset where I want to have some of the controls disabled if an input is connected. Similar to the Box SOP, where it disables the Size and Center if you connect a node to its input.

I just don't know how to detect this at the asset level and use it in the Disabled When field.

Thanks

[ranxerox]

can you use opinput and test if it returns a null string ?

-G

Hi,

I am making an asset where I want to have some of the controls disabled if an input is connected. Similar to the Box SOP, where it disables the Size and Center if you connect a node to its input.

I just don't know how to detect this at the asset level and use it in the Disabled When field.

Thanks

[magneto]

I tried the opinput inside the Disabled When field but it didn't work. Can I use those expressions inside Disabled When? I thought that field has a very specific limited syntax for logic.

[Annon]

Set up an integer field that you then make it invisible (lets say "hasConnection".

Then use a little python, look up hou.node.inputs.

Do something like (might be wrong, it's off the top of my head and I hardly ever code):

node = hou.pwd()
inputs = node.inputs()

if not inputs:
     return 1
else:
     return 0

then you could disable a folder or any other parameter based on the result of the int field. Disable if:

[hasConnection == 0]

Something like that should work.

Hope that helps Magneto.

Christian

[magneto]

Wow that's an awesome trick. Thanks Christian

[anim]

hidden int parms are usually used for this

but maybe rather than using python for the simple expression you can use hscript like

opninputs(".") == 1

or more specificlally as ranxerox suggested

opinput(".",1) == ""

Edited August 2, 2012 by anim

[hopbin9]

If you put this Python expression in a parameter it will be True if input connector #3 is connected to something.

len([1 for c in hou.pwd().inputConnections() if c.inputIndex() == 2])

NOTE: inputIndex starts at zero.

[magneto]

Thanks alot guys, really cool tricks

Btw all these codes are to be used as Default Expression for the parameter right?

[hopbin9]

I would put it in the Scripts section under the "On Input Changed" and have it set a parameter value to 0/1 when the inputs change.

[magneto]

Thanks hopbin, got it. I was using the default expression. Both should work I guess.