Distance based mask

[Muhammad Junaid Baig]

Hi,

I'm new to this forum and a young player of Houdini as well. My question is fairly simple in nature, but I can't seem to figure out the answer.

What I want is to basically mask one object with another object's distance and say color falloff.

For example, to elaborate further (I'll describe in layman's terms); consider I have one sphere and one pre-fractured sphere. Now I want my pre-fractured sphere to appear within the falloff of another proximity object.

Does it make sense?

Thanks in anticipation.

[acey195]

Hi,

Can you not just use something like a distance() expression?

If you want to create a falloff I would use a VOPSOP.

You put the object you want to color in the first input and a single point for the other position in the second Input.

Then you import the position attribute of the point of the second input inside.

Set the input of the node to 1 instead of 0, so it reads from the second input and set a constant 0 for this point number.

Then you add a distance node and connect the importAttrib and the main point position input and connect this to the Color output, or a custom Attribute.

Hope that helps

[Filipp Elizarov]

Hi,Just did a small scene for you.Think it will help to understand better how it works. In scene you can move sphere2 and will see the changes.

distance.hip

Edited April 9, 2013 by Filipp Elizarov

[Muhammad Junaid Baig]

Wow! This community is really awesome. Thanks a lot mates. Twan de Graaf, I'll dig into what you mentioned, can't just get it on the fly at the moment. Filipp Elizarov, That is really a helpful file. Thanks for that.

I have set something up with the ray sop but I'm not truly there yet. Under the current topic, I have another question. Is it not possibe - or - simple in Houdini to mask any node? Like we do in Naiad and Nuke?

Best,

[Filipp Elizarov]

You can put any object you want to a group with Group Sop and as you may know or will know each Houdini operator SOP and a lot others can affect all geometry or affect geo by group.Usually its menu on top of each operator and called Group - here you can add your group which previously should be created and affect only on it.Think it will help.(Read carefully about Group sop , Connectivity node + Partition node and Copy node with stamping + read about For Each Sop togeather they are really powerfull)

[Muhammad Junaid Baig]

Wonderful! Thanks Filipp. I had this idea about groups, but I believe I need to dig deeper in that, because I sometimes face problems after creating & calling in groups.

Best,