Procdural Modeling, Lesson 1 Hoses and Pipes at around 52 minutes Ari lays down a VOP SOP. In Houdini 14.0.436 Apprentice there is no such VOP, so I tried out pointvop and vertexvop.

However, Ari groups the collected points using a “Add point to group”, and I can't find that one when I dive into the geometryvopoutput in either of the VOPs I tried, and I get errors trying to lay anything down “Failed to modify node or parameter because of permission error”, so they are locked (greyed out) and have more nodes than in Ari's video.

There is an “Add Point”, but I have no good idea how to use that, and there are stuff to add to stacks and arrays, which I guess would do the work for collecting the points, but without anything to add them to a group I'm stumped.

So my questions are:

Where should I start to learn more about VOPs? I'll turn to the online documentation first, but any suggestions for videos that are current would be nice.

Best regards,
Paul

Actually, there are not lot of videos concerning the VOPs in Hou14 that I know of, maybe you could try rohan dalvi last video rocket tutorial available at this adress (http://www.rohandalvi.net/rocket) [rohandalvi.net]

About your other questions, the add point to group node has been removed. Now, if you want to set a point in a group, you need to use a “Set Attribute” node set to point group and an integer value (1 means the point belong to the group)

Here is the hip file

Yeah, that should be updated, or at least mention a fix in the comments.

Anyways, I've attached another way to do it. The newer way is to treat it as if you're getting and setting point attributes, but if you prefix the attribute name with ‘group_’, it treats it as getting and setting group membership. Setting the value to 1 adds to the group, 0 removes it.

It's a little easier to understand in vex, I've included a point wrangle that does the same thing.

Re learning vops, this odforce thread is pretty good…

http://forums.odforce.net/topic/20792-learning-vopsop/ [forums.odforce.net]

… and I've been trying to keep my stack of wiki examples up to date.

http://www.tokeru.com/mayawiki/index.php?title=Houdini [tokeru.com]


-matt

Thank you for your help. I will look into the Set Attribute.

And I'll read more in the documentation to learn what all these Houdini acronyms mean.

Best regards,
Paul