In all the workflows that I've seen in tutorials so far, whenever there is a ramp parameter created inside a VOP network, it is always controlled outside the VOP network in the Geometry network. Why is that? Similarly, parameter node is also created inside the VOP but always ends up getting controlled outside the VOP network in the Geometry network. Why? I know that it's a thumb rule that any yellow coloured node inside the VOP gets is supposed to be controlled outside it. But why?

I mean, if these things are supposed to be controlled in the geo network, why do they show up with controllable numerical values inside the VOP?

proceduralist
In all the workflows that I've seen in tutorials so far, whenever there is a ramp parameter created inside a VOP network, it is always controlled outside the VOP network in the Geometry network. Why is that? Similarly, parameter node is also created inside the VOP but always ends up getting controlled outside the VOP network in the Geometry network. Why? I know that it's a thumb rule that any yellow coloured node inside the VOP gets is supposed to be controlled outside it. But why?

I mean, if these things are supposed to be controlled in the geo network, why do they show up with controllable numerical values inside the VOP?

All parameters work that way. The value on the parameter node is just the default value.

Okay, then why is there a feature to control the ramp inside the VOP?

Because Ramp parameters are similar to Multiparm block parameters, you can set a default value for ramps as well.

Main reason is that VOP network doesn't use precompiled nodes, it is merely a visual description of VEX code which gets generated and shader gets compiled

For that reason parameters on VOP nodes inside of the VOPnet shouldn't be animated
Therefore any shader UI is represented using Parameter VOP or Ramp Parameter VOP whose will create corresponding animatable shader inputs

You can create editable ramp UI inside VOP net if you enclose Ramp Parameter in a subnet and change to Subnet Connector instead of Shader Parameter

Jikian
Because Ramp parameters are similar to Multiparm block parameters, you can set a default value for ramps as well.

Okay. I don't know anything about Multiparm block parameters. I'll have to do some reading on it.

In general, you should immediately promote all parms you expect to fiddle with. For small networks, not doing this might not slow you down, but for larger ones, it definitely will. Each time you change a value inside the network, the whole network has to be recompiled... whereas if you make the same changes to a promoted parm, the network is not recompiled.

mrCatfish
In general, you should immediately promote all parms you expect to fiddle with. For small networks, not doing this might not slow you down, but for larger ones, it definitely will. Each time you change a value inside the network, the whole network has to be recompiled... whereas if you make the same changes to a promoted parm, the network is not recompiled.

Okay. Yeah. I heard this phenomena of vop networks slowing down when changing a parameter inside them in some tutorial. I believe I should accept this as a standard good practice instead of trying to find out the reasons behind it. I guess while learning Houdini, there are some boundaries that one has to set while trying to find out the reasons for everything that's happening. I feel that in this scenario, I am trying to get too deep in the rabbit hole and the answers that I find there may not help me in learning Houdini or improving my workflow.