Is it possible to set a parameter value when a certain menu item is ch

[magneto]

Hi,

I am not sure if this is possible, but I want to set an integer parameter to a calculated value from the UI, when a certain menu item is picked.

So let's say the user picked "poly" from the Primitive Type menu, I want to set an integer field to ch("sx") for instance.

Is this doable?

Thanks

[anim]

sure you can use parameter callback script to set that directly

or usually if it's from your asset you can call some function from HDA Python module which will do something when that parameter is changed

[magneto]

Thanks anim. I looked around but is there any example you know of?

Edited August 6, 2012 by magneto

[anim]

this may be helpful for you

http://www.sidefx.com/docs/houdini12.0/hom/assetscripts

as an example I don't remember a particular one, but with a little search here and on sidefx for "callback" you should get plenty of interesting posts

or maybe if you specify more what you want I cam make the example

[magneto]

Thanks anim, will check it out now. Basically I want to set a value of a numeric parameter, let's say when you select Primitive Type "poly", I want to set the height to 5. That sort of thing. But after that the user is free to adjust that parameter himself, so it's not locked but just set to an initial value for a particular option.

[anim]

here is simple example

simple_callback.hip

[magneto]

Thanks anim, very useful example. I never used callbacks before so this is very helpful.

EDIT: Although I tried to create it from scratch but getting this error:

    def __getattr__(*args): return _hou.HDAModule___getattr__(*args)
AttributeError: 'module' object has no attribute 'setHeight'

I am using setHeight like you both for the function name, and the callback function call in the parameter.

Edited August 6, 2012 by magneto

[anim]

it tells you that setHeight() function does not exist

you need to define that function in your asset

setHeight() is function I created in Scripts tab of the Asset, by creating Python Module and filled it with definition

so you need to define your function there if you want to call it, or of course you can call any function declared anywhere else

[magneto]

Yeah I saw that in your hip file, and added a function, but that's how I got the error. Let me see if I can create a simple test case.

EDIT: I think I found the problem. It's because of namespaces. Does this change how the callback function should be used?

hou.phm().setHeight(kwargs)

Will be something else?

Edited August 6, 2012 by magneto

[anim]

it shouldn't be namespaces since hou.phm() should point to current nodes python module

but you can try:

kwargs['node'].hdaModule().setHeight(kwargs)

or post your file so we can check it

[magneto]

Thanks anim, you are right. Namespacing doesn't do it. I am not able to reproduce it. I will see if I can make something

[magneto]

I found the problem, it was due to some error in the script, which Houdini showed an error message for not being able to find the function because it was failed to be defined. It might be because of maybe I sent the errors to the console and it only printed the last error or I missed it. But it works now.

Thanks anim